Commit Graph

26649 Commits

Author SHA1 Message Date
Tejun Heo
40c17f75df workqueue: allow WQ_MEM_RECLAIM on early init workqueues
Workqueues can be created early during boot before workqueue subsystem
in fully online - work items are queued waiting for later full
initialization.  However, early init wasn't supported for
WQ_MEM_RECLAIM workqueues causing unnecessary annoyances for a subset
of users.  Expand early init support to include WQ_MEM_RECLAIM
workqueues.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
2018-01-08 05:38:37 -08:00
Tejun Heo
983c751532 workqueue: separate out init_rescuer()
Separate out init_rescuer() from __alloc_workqueue_key() to prepare
for early init support for WQ_MEM_RECLAIM.  This patch doesn't
introduce any functional changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
2018-01-08 05:38:32 -08:00
Linus Torvalds
75d4276e83 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:

 - untangle sys_close() abuses in xt_bpf

 - deal with register_shrinker() failures in sget()

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fix "netfilter: xt_bpf: Fix XT_BPF_MODE_FD_PINNED mode of 'xt_bpf_info_v1'"
  sget(): handle failures of register_shrinker()
  mm,vmscan: Make unregister_shrinker() no-op if register_shrinker() failed.
2018-01-06 17:13:21 -08:00
John Fastabend
5731a879d0 bpf: sockmap missing NULL psock check
Add psock NULL check to handle a racing sock event that can get the
sk_callback_lock before this case but after xchg happens causing the
refcnt to hit zero and sock user data (psock) to be null and queued
for garbage collection.

Also add a comment in the code because this is a bit subtle and
not obvious in my opinion.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-01-07 00:01:46 +01:00
Ming Lei
263663cd3c block: convert to bio_first_bvec_all & bio_first_page_all
This patch converts to bio_first_bvec_all() & bio_first_page_all() for
retrieving the 1st bvec/page, and prepares for supporting multipage bvec.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06 09:18:00 -07:00
Al Viro
a4a0683fd5 bpf_obj_do_pin(): switch to vfs_mkobj(), quit abusing ->mknod()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-01-05 11:54:33 -05:00
Al Viro
040ee69226 fix "netfilter: xt_bpf: Fix XT_BPF_MODE_FD_PINNED mode of 'xt_bpf_info_v1'"
Descriptor table is a shared object; it's not a place where you can
stick temporary references to files, especially when we don't need
an opened file at all.

Cc: stable@vger.kernel.org # v4.14
Fixes: 98589a0998 ("netfilter: xt_bpf: Fix XT_BPF_MODE_FD_PINNED mode of 'xt_bpf_info_v1'")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-01-05 11:43:39 -05:00
Rainer Fiebig
bdbc98abb3 PM: hibernate: Do not subtract NR_FILE_MAPPED in minimum_image_size()
s2disk/s2both may fail unnecessarily and erratically if NR_FILE_MAPPED
is high - for instance when using VMs with VirtualBox and perhaps VMware
Player. In those situations s2disk becomes unreliable and therefore
unusable.

A typical scenario is: user issues a s2disk and it fails. User issues
a second s2disk immediately after that and it succeeds.  And user
wonders why.

The problem is caused by minimum_image_size() in snapshot.c.  The
value it returns is roughly 100% too high because NR_FILE_MAPPED is
subtracted in its calculation.  Eventually the number of preallocated
image pages is falsely too low.

This doesn't matter as long as NR_FILE_MAPPED-values are in a normal
range or in 32bit-environments as the code allows for allocation of
additional pages from highmem.

But with the high values generated by VirtualBox-VMs (a 2-GB-VM causes
NR_FILE_MAPPED go up by 2 GB) it may lead to failure in 64bit-systems.

Not subtracting NR_FILE_MAPPED in minimum_image_size() solves the
problem.

I've done at least hundreds of successful s2both/s2disk now on an
x86_64 system (with and without VirtualBox) which gives me some
confidence that this is right.  It has turned s2disk/s2both from
unusable into 100% reliable.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=97201
Signed-off-by: Rainer Fiebig <jrf@mailbox.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-01-05 14:46:25 +01:00
Andrew Morton
dc8635b78c kernel/exit.c: export abort() to modules
gcc -fisolate-erroneous-paths-dereference can generate calls to abort()
from modular code too.

[arnd@arndb.de: drop duplicate exports of abort()]
  Link: http://lkml.kernel.org/r/20180102103311.706364-1-arnd@arndb.de
Reported-by: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Jose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-01-04 16:45:09 -08:00
Oleg Nesterov
4d9570158b kernel/acct.c: fix the acct->needcheck check in check_free_space()
As Tsukada explains, the time_is_before_jiffies(acct->needcheck) check
is very wrong, we need time_is_after_jiffies() to make sys_acct() work.

Ignoring the overflows, the code should "goto out" if needcheck >
jiffies, while currently it checks "needcheck < jiffies" and thus in the
likely case check_free_space() does nothing until jiffies overflow.

In particular this means that sys_acct() is simply broken, acct_on()
sets acct->needcheck = jiffies and expects that check_free_space()
should set acct->active = 1 after the free-space check, but this won't
happen if jiffies increments in between.

This was broken by commit 32dc730860 ("get rid of timer in
kern/acct.c") in 2011, then another (correct) commit 795a2f22a8
("acct() should honour the limits from the very beginning") made the
problem more visible.

Link: http://lkml.kernel.org/r/20171213133940.GA6554@redhat.com
Fixes: 32dc730860 ("get rid of timer in kern/acct.c")
Reported-by: TSUKADA Koutaro <tsukada@ascade.co.jp>
Suggested-by: TSUKADA Koutaro <tsukada@ascade.co.jp>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-01-04 16:45:09 -08:00
Nick Desaulniers
29f1b2b0fe posix-timers: Prevent UB from shifting negative signed value
Shifting a negative signed number is undefined behavior. Looking at the
macros MAKE_PROCESS_CPUCLOCK and FD_TO_CLOCKID, it seems that the
subexpression:

(~(clockid_t) (pid) << 3)

where clockid_t resolves to a signed int, which once negated, is
undefined behavior to shift the value of if the results thus far are
negative.

It was further suggested to make these macros into inline functions.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Nick Desaulniers <nick.desaulniers@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Dimitri Sivanich <sivanich@hpe.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-kselftest@vger.kernel.org
Cc: Shuah Khan <shuah@kernel.org>
Cc: Deepa Dinamani <deepa.kernel@gmail.com>
Link: https://lkml.kernel.org/r/1514517100-18051-1-git-send-email-nick.desaulniers@gmail.com
2018-01-04 14:57:10 +01:00
Eric W. Biederman
0b44bf9a6f signal: Simplify and fix kdb_send_sig
- Rename from kdb_send_sig_info to kdb_send_sig
  As there is no meaningful siginfo sent

- Use SEND_SIG_PRIV instead of generating a siginfo for a kdb
  signal.  The generated siginfo had a bogus rationale and was
  not correct in the face of pid namespaces.  SEND_SIG_PRIV
  is simpler and actually correct.

- As the code grabs siglock just send the signal with siglock
  held instead of dropping siglock and attempting to grab it again.

- Move the sig_valid test into kdb_kill where it can generate
  a good error message.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2018-01-03 18:01:08 -06:00
Linus Torvalds
d6bbd51587 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull pid allocation bug fix from Eric Biederman:
 "The replacement of the pid hash table and the pid bitmap with an idr
  resulted in an implementation that now fails more often in low memory
  situations. Allowing fuzzers to observe bad behavior from a memory
  allocation failure during pid allocation.

  This is a small change to fix this by making the kernel more robust in
  the case of error. The non-error paths are left alone so the only
  danger is to the already broken error path. I have manually injected
  errors and verified that this new error handling works"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  pid: Handle failure to allocate the first pid in a pid namespace
2018-01-03 11:03:07 -08:00
Ingo Molnar
475c5ee193 Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU updates from Paul E. McKenney:

- Updates to use cond_resched() instead of cond_resched_rcu_qs()
  where feasible (currently everywhere except in kernel/rcu and
  in kernel/torture.c).  Also a couple of fixes to avoid sending
  IPIs to offline CPUs.

- Updates to simplify RCU's dyntick-idle handling.

- Updates to remove almost all uses of smp_read_barrier_depends()
  and read_barrier_depends().

- Miscellaneous fixes.

- Torture-test updates.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-03 14:14:18 +01:00
Suzuki K Poulose
82975c46da perf: Export perf_event_update_userpage
Export perf_event_update_userpage() so that PMU driver using them,
can be built as modules.

Acked-by: Peter Zilstra <peterz@infradead.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-01-02 16:43:12 +00:00
Linus Torvalds
cea92e843e Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
 "A pile of fixes for long standing issues with the timer wheel and the
  NOHZ code:

   - Prevent timer base confusion accross the nohz switch, which can
     cause unlocked access and data corruption

   - Reinitialize the stale base clock on cpu hotplug to prevent subtle
     side effects including rollovers on 32bit

   - Prevent an interrupt storm when the timer softirq is already
     pending caused by tick_nohz_stop_sched_tick()

   - Move the timer start tracepoint to a place where it actually makes
     sense

   - Add documentation to timerqueue functions as they caused confusion
     several times now"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timerqueue: Document return values of timerqueue_add/del()
  timers: Invoke timer_start_debug() where it makes sense
  nohz: Prevent a timer interrupt storm in tick_nohz_stop_sched_tick()
  timers: Reinitialize per cpu bases on hotplug
  timers: Use deferrable base independent of base::nohz_active
2017-12-31 12:30:34 -08:00
Linus Torvalds
8d517bdfb5 Merge branch 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull smp fixlet from Thomas Gleixner:
 "A trivial build warning fix for newer compilers"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  cpu/hotplug: Move inline keyword at the beginning of declaration
2017-12-31 12:29:02 -08:00
Linus Torvalds
4c470317f9 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Thomas Gleixner:
 "Three patches addressing the fallout of the CPU_ISOLATION changes
  especially with NO_HZ_FULL plus documentation of boot parameter
  dependency"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/isolation: Document boot parameters dependency on CONFIG_CPU_ISOLATION=y
  sched/isolation: Enable CONFIG_CPU_ISOLATION=y by default
  sched/isolation: Make CONFIG_NO_HZ_FULL select CONFIG_CPU_ISOLATION
2017-12-31 12:27:19 -08:00
Linus Torvalds
88fa025d30 Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:
 "A rather large update after the kaisered maintainer finally found time
  to handle regression reports.

   - The larger part addresses a regression caused by the x86 vector
     management rework.

     The reservation based model does not work reliably for MSI
     interrupts, if they cannot be masked (yes, yet another hw
     engineering trainwreck). The reason is that the reservation mode
     assigns a dummy vector when the interrupt is allocated and switches
     to a real vector when the interrupt is requested.

     If the MSI entry cannot be masked then the initialization might
     raise an interrupt before the interrupt is requested, which ends up
     as spurious interrupt and causes device malfunction and worse. The
     fix is to exclude MSI interrupts which do not support masking from
     reservation mode and assign a real vector right away.

   - Extend the extra lockdep class setup for nested interrupts with a
     class for the recently added irq_desc::request_mutex so lockdep can
     differeniate and does not emit false positive warnings.

   - A ratelimit guard for the bad irq printout so in case a bad irq
     comes back immediately the system does not drown in dmesg spam"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/msi, x86/vector: Prevent reservation mode for non maskable MSI
  genirq/irqdomain: Rename early argument of irq_domain_activate_irq()
  x86/vector: Use IRQD_CAN_RESERVE flag
  genirq: Introduce IRQD_CAN_RESERVE flag
  genirq/msi: Handle reactivation only on success
  gpio: brcmstb: Make really use of the new lockdep class
  genirq: Guard handle_bad_irq log messages
  kernel/irq: Extend lockdep class for request mutex
2017-12-31 11:23:11 -08:00
Thomas Gleixner
fd45bb77ad timers: Invoke timer_start_debug() where it makes sense
The timer start debug function is called before the proper timer base is
set. As a consequence the trace data contains the stale CPU and flags
values.

Call the debug function after setting the new base and flags.

Fixes: 500462a9de ("timers: Switch to a non-cascading wheel")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: stable@vger.kernel.org
Cc: rt@linutronix.de
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>
Link: https://lkml.kernel.org/r/20171222145337.792907137@linutronix.de
2017-12-29 23:13:10 +01:00
Thomas Gleixner
5d62c183f9 nohz: Prevent a timer interrupt storm in tick_nohz_stop_sched_tick()
The conditions in irq_exit() to invoke tick_nohz_irq_exit() which
subsequently invokes tick_nohz_stop_sched_tick() are:

  if ((idle_cpu(cpu) && !need_resched()) || tick_nohz_full_cpu(cpu))

If need_resched() is not set, but a timer softirq is pending then this is
an indication that the softirq code punted and delegated the execution to
softirqd. need_resched() is not true because the current interrupted task
takes precedence over softirqd.

Invoking tick_nohz_irq_exit() in this case can cause an endless loop of
timer interrupts because the timer wheel contains an expired timer, but
softirqs are not yet executed. So it returns an immediate expiry request,
which causes the timer to fire immediately again. Lather, rinse and
repeat....

Prevent that by adding a check for a pending timer soft interrupt to the
conditions in tick_nohz_stop_sched_tick() which avoid calling
get_next_timer_interrupt(). That keeps the tick sched timer on the tick and
prevents a repetitive programming of an already expired timer.

Reported-by: Sebastian Siewior <bigeasy@linutronix.d>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1712272156050.2431@nanos
2017-12-29 23:13:10 +01:00
Thomas Gleixner
26456f87ac timers: Reinitialize per cpu bases on hotplug
The timer wheel bases are not (re)initialized on CPU hotplug. That leaves
them with a potentially stale clk and next_expiry valuem, which can cause
trouble then the CPU is plugged.

Add a prepare callback which forwards the clock, sets next_expiry to far in
the future and reset the control flags to a known state.

Set base->must_forward_clk so the first timer which is queued will try to
forward the clock to current jiffies.

Fixes: 500462a9de ("timers: Switch to a non-cascading wheel")
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1712272152200.2431@nanos
2017-12-29 23:13:09 +01:00
Anna-Maria Gleixner
ced6d5c11d timers: Use deferrable base independent of base::nohz_active
During boot and before base::nohz_active is set in the timer bases, deferrable
timers are enqueued into the standard timer base. This works correctly as
long as base::nohz_active is false.

Once it base::nohz_active is set and a timer which was enqueued before that
is accessed the lock selector code choses the lock of the deferred
base. This causes unlocked access to the standard base and in case the
timer is removed it does not clear the pending flag in the standard base
bitmap which causes get_next_timer_interrupt() to return bogus values.

To prevent that, the deferrable timers must be enqueued in the deferrable
base, even when base::nohz_active is not set. Those deferrable timers also
need to be expired unconditional.

Fixes: 500462a9de ("timers: Switch to a non-cascading wheel")
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: stable@vger.kernel.org
Cc: rt@linutronix.de
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Link: https://lkml.kernel.org/r/20171222145337.633328378@linutronix.de
2017-12-29 23:13:09 +01:00
Thomas Gleixner
bc976233a8 genirq/msi, x86/vector: Prevent reservation mode for non maskable MSI
The new reservation mode for interrupts assigns a dummy vector when the
interrupt is allocated and assigns a real vector when the interrupt is
requested. The reservation mode prevents vector pressure when devices with
a large amount of queues/interrupts are initialized, but only a minimal
subset of those queues/interrupts is actually used.

This mode has an issue with MSI interrupts which cannot be masked. If the
driver is not careful or the hardware emits an interrupt before the device
irq is requestd by the driver then the interrupt ends up on the dummy
vector as a spurious interrupt which can cause malfunction of the device or
in the worst case a lockup of the machine.

Change the logic for the reservation mode so that the early activation of
MSI interrupts checks whether:

 - the device is a PCI/MSI device
 - the reservation mode of the underlying irqdomain is activated
 - PCI/MSI masking is globally enabled
 - the PCI/MSI device uses either MSI-X, which supports masking, or
   MSI with the maskbit supported.

If one of those conditions is false, then clear the reservation mode flag
in the irq data of the interrupt and invoke irq_domain_activate_irq() with
the reserve argument cleared. In the x86 vector code, clear the can_reserve
flag in the vector allocation data so a subsequent free_irq() won't create
the same situation again. The interrupt stays assigned to a real vector
until pci_disable_msi() is invoked and all allocations are undone.

Fixes: 4900be8360 ("x86/vector/msi: Switch to global reservation mode")
Reported-by: Alexandru Chirvasitu <achirvasub@gmail.com>
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexandru Chirvasitu <achirvasub@gmail.com>
Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Dou Liyang <douly.fnst@cn.fujitsu.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Mikael Pettersson <mikpelinux@gmail.com>
Cc: Josh Poulson <jopoulso@microsoft.com>
Cc: Mihai Costache <v-micos@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-pci@vger.kernel.org
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Simon Xiao <sixiao@microsoft.com>
Cc: Saeed Mahameed <saeedm@mellanox.com>
Cc: Jork Loeser <Jork.Loeser@microsoft.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: devel@linuxdriverproject.org
Cc: KY Srinivasan <kys@microsoft.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Sakari Ailus <sakari.ailus@intel.com>,
Cc: linux-media@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1712291406420.1899@nanos
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1712291409460.1899@nanos
2017-12-29 21:13:05 +01:00
Thomas Gleixner
702cb0a028 genirq/irqdomain: Rename early argument of irq_domain_activate_irq()
The 'early' argument of irq_domain_activate_irq() is actually used to
denote reservation mode. To avoid confusion, rename it before abuse
happens.

No functional change.

Fixes: 7249164346 ("genirq/irqdomain: Update irq_domain_ops.activate() signature")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Alexandru Chirvasitu <achirvasub@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Dou Liyang <douly.fnst@cn.fujitsu.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Mikael Pettersson <mikpelinux@gmail.com>
Cc: Josh Poulson <jopoulso@microsoft.com>
Cc: Mihai Costache <v-micos@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-pci@vger.kernel.org
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Simon Xiao <sixiao@microsoft.com>
Cc: Saeed Mahameed <saeedm@mellanox.com>
Cc: Jork Loeser <Jork.Loeser@microsoft.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: devel@linuxdriverproject.org
Cc: KY Srinivasan <kys@microsoft.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Sakari Ailus <sakari.ailus@intel.com>,
Cc: linux-media@vger.kernel.org
2017-12-29 21:13:04 +01:00
Thomas Gleixner
69790ba92b genirq: Introduce IRQD_CAN_RESERVE flag
Add a new flag to mark interrupts which can use reservation mode. This is
going to be used in subsequent patches to disable reservation mode for a
certain class of MSI devices.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexandru Chirvasitu <achirvasub@gmail.com>
Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Dou Liyang <douly.fnst@cn.fujitsu.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Mikael Pettersson <mikpelinux@gmail.com>
Cc: Josh Poulson <jopoulso@microsoft.com>
Cc: Mihai Costache <v-micos@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-pci@vger.kernel.org
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Simon Xiao <sixiao@microsoft.com>
Cc: Saeed Mahameed <saeedm@mellanox.com>
Cc: Jork Loeser <Jork.Loeser@microsoft.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: devel@linuxdriverproject.org
Cc: KY Srinivasan <kys@microsoft.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Sakari Ailus <sakari.ailus@intel.com>,
Cc: linux-media@vger.kernel.org
2017-12-29 21:13:04 +01:00
Thomas Gleixner
da5dd9e854 genirq/msi: Handle reactivation only on success
When analyzing the fallout of the x86 vector allocation rework it turned
out that the error handling in msi_domain_alloc_irqs() is broken.

If MSI_FLAG_MUST_REACTIVATE is set for a MSI domain then it clears the
activation flag for a successfully initialized msi descriptor. If a
subsequent initialization fails then the error handling code path does not
deactivate the interrupt because the activation flag got cleared.

Move the clearing of the activation flag outside of the initialization loop
so that an eventual failure can be cleaned up correctly.

Fixes: 22d0b12f35 ("genirq/irqdomain: Add force reactivation flag to irq domains")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexandru Chirvasitu <achirvasub@gmail.com>
Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Dou Liyang <douly.fnst@cn.fujitsu.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Mikael Pettersson <mikpelinux@gmail.com>
Cc: Josh Poulson <jopoulso@microsoft.com>
Cc: Mihai Costache <v-micos@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-pci@vger.kernel.org
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Simon Xiao <sixiao@microsoft.com>
Cc: Saeed Mahameed <saeedm@mellanox.com>
Cc: Jork Loeser <Jork.Loeser@microsoft.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: devel@linuxdriverproject.org
Cc: KY Srinivasan <kys@microsoft.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Sakari Ailus <sakari.ailus@intel.com>,
Cc: linux-media@vger.kernel.org
2017-12-29 21:13:04 +01:00
Linus Torvalds
61233580f1 Power management fix for v4.15-rc6
This fixes a schedutil cpufreq governor regression from the 4.14
 cycle that may cause a CPU idleness check to return incorrect results
 in some cases which leads to suboptimal decisions (Joel Fernandes).
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQIcBAABCAAGBQJaROaWAAoJEILEb/54YlRxCNMP/3Dr1wAhR26HgVyAVXN3tR8j
 RjYvn/G7WFuczl+nqsMT8A2Gig61BAWVhADh5HJrqoZbYlwOLXCnMJOcQy4FDy2g
 THPQdzf8eT0OHGF/+SZvOWTPX+nL63cN+i+U1bCYyuQ6+N1Kk3vZdMx8fbyJScQ2
 KtszEg1zh2CIzHSDlxqQFOzE8O2GAU+evBQYMrwLpPBUbi9yN9nCZJ8XKarfJwnB
 YgALt0BdLU+n7kFj4ZCx76Mjf3qQL7rV+3YNs49OJU90p72O4aiadv7XxDMv5Fpf
 Ie9xh0gouZLPziJiHwFPb3PqxMVojJPKpqRk73mitCc2T93Kk4oWozGt60k0tahO
 pYBh2OGHycnMI/cn2wpOk/hIdHVz6IUD5Of8LtXAiDhAnmvlj5PFdnHGDgvMwbga
 2Kzbw8n2fKfiX2r9UfJRjrQHaomvdy4kgneMVjgrh0dIu9GL5zK2sntF0pZeyyKH
 XzIBZ9Ue1PLOWIDW1LSPLMq6YKh95FLRTebodiWRbq2CYITCXn37qGMd4BhXwOEx
 CLkSE3vmWbh6Yr6pITlFU0oTMenc0SCHAqh+hHTr4NAYA5rooLspH0swRk5Lf2bz
 OC7K4BkPc0Lyv2MUj5ZKYa3UCgJ9QF/ekL4JW4PsWRZ1Afk8XqiCC5O9Kn4/iYGT
 xzcKW02R1p/hIWTOY2kw
 =TPkr
 -----END PGP SIGNATURE-----

Merge tag 'pm-4.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fix from Rafael Wysocki:
 "This fixes a schedutil cpufreq governor regression from the 4.14 cycle
  that may cause a CPU idleness check to return incorrect results in
  some cases which leads to suboptimal decisions (Joel Fernandes)"

* tag 'pm-4.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpufreq: schedutil: Use idle_calls counter of the remote CPU
2017-12-29 11:54:15 -08:00
Guenter Roeck
11bca0a83f genirq: Guard handle_bad_irq log messages
An interrupt storm on a bad interrupt will cause the kernel
log to be clogged.

[   60.089234] ->handle_irq():  ffffffffbe2f803f,
[   60.090455] 0xffffffffbf2af380
[   60.090510] handle_bad_irq+0x0/0x2e5
[   60.090522] ->irq_data.chip(): ffffffffbf2af380,
[   60.090553]    IRQ_NOPROBE set
[   60.090584] ->handle_irq():  ffffffffbe2f803f,
[   60.090590] handle_bad_irq+0x0/0x2e5
[   60.090596] ->irq_data.chip(): ffffffffbf2af380,
[   60.090602] 0xffffffffbf2af380
[   60.090608] ->action():           (null)
[   60.090779] handle_bad_irq+0x0/0x2e5

This was seen when running an upstream kernel on Acer Chromebook R11.  The
system was unstable as result.

Guard the log message with __printk_ratelimit to reduce the impact.  This
won't prevent the interrupt storm from happening, but at least the system
remains stable.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Dmitry Torokhov <dtor@chromium.org>
Cc: Joe Perches <joe@perches.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=197953
Link: https://lkml.kernel.org/r/1512234784-21038-1-git-send-email-linux@roeck-us.net
2017-12-28 12:28:29 +01:00
Joel Fernandes
466a2b42d6 cpufreq: schedutil: Use idle_calls counter of the remote CPU
Since the recent remote cpufreq callback work, its possible that a cpufreq
update is triggered from a remote CPU. For single policies however, the current
code uses the local CPU when trying to determine if the remote sg_cpu entered
idle or is busy. This is incorrect. To remedy this, compare with the nohz tick
idle_calls counter of the remote CPU.

Fixes: 674e75411f (sched: cpufreq: Allow remote cpufreq callbacks)
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Joel Fernandes <joelaf@google.com>
Cc: 4.14+ <stable@vger.kernel.org> # 4.14+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-12-28 12:26:54 +01:00
Andrew Lunn
39c3fd5895 kernel/irq: Extend lockdep class for request mutex
The IRQ code already has support for lockdep class for the lock mutex
in an interrupt descriptor. Extend this to add a second class for the
request mutex in the descriptor. Not having a class is resulting in
false positive splats in some code paths.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: linus.walleij@linaro.org
Cc: grygorii.strashko@ti.com
Cc: f.fainelli@gmail.com
Link: https://lkml.kernel.org/r/1512234664-21555-1-git-send-email-andrew@lunn.ch
2017-12-28 12:26:35 +01:00
Linus Torvalds
5f520fc318 While doing tests on tracing over the network, I found that the packets
were getting corrupted. In the process I found three bugs. One was the
 culprit, but the other two scared me. After deeper investigation, they
 were not as major as I thought they were, due to a signed compared to
 an unsigned that prevented a negative number from doing actual harm.
 
 The two bigger bugs:
 
  - Mask the ring buffer data page length. There are data flags at the
    high bits of the length field. These were not cleared via the
    length function, and the length could return a negative number.
    (Although the number returned was unsigned, but was assigned to a
    signed number) Luckily, this value was compared to PAGE_SIZE which is
    unsigned and kept it from entering the path that could have caused damage.
 
  - Check the page usage before reusing the ring buffer reader page.
    TCP increments the page ref when passing the page off to the network.
    The page is passed back to the ring buffer for use on free. But
    the page could still be in use by the TCP stack.
 
 Minor bugs:
 
  - Related to the first bug. No need to clear out the unused ring buffer
    data before sending to user space. It is now done by the ring buffer
    code itself.
 
  - Reset pointers after free on error path. There were some cases in
    the error path that pointers were freed but not set to NULL, and could
    have them freed again, having a pointer freed twice.
 -----BEGIN PGP SIGNATURE-----
 
 iQHIBAABCgAyFiEEPm6V/WuN2kyArTUe1a05Y9njSUkFAlpD9O8UHHJvc3RlZHRA
 Z29vZG1pcy5vcmcACgkQ1a05Y9njSUnC0Av9EqzJjJXlZuleCSiuh1umx33esgZv
 gOYTOXH9QLdKFHLpwVzeCsrhrLXNhbUfrGMQ0ERcpvVacHCKVwRyzx0nfI5W3rbt
 9sCsNsVR2SCVpzSWOvP9iJM0J/myFdZtYmGLC2BBJerXZFwl9Ciw+1bF7MFprb4v
 6r+49YrYMAR/H/obT3Aoh/XCOz0W0czk9ECGPhuwqAjWoNPwSgpbTdqpR92bJf85
 hGYppIX9d+4Gv4pZ2lfXDKrgiAPvHpp5I/znLDY8cG7GhcBjyXaetBb+XlfHI6D4
 jTS59f13CqcEhyFE5x2qwQBr9TTh043EKviixDud+nI1L7aNhDIBtb6tYrAmGWWh
 Rj1268gFjspi3pYTjI8cHXXCJSdQiAqFesiFLviU1c17PgjbBAnmkcsFSgOPxHqc
 j225jravcXtUqQq5J0qKR6Sn3LObfYJQk6tqpN6gWN76P75QgUms5W4+/NiEI0a3
 0LVjapxHZkDEYNRGmI+d0CvIJ3BWyb781Siw
 =xhPf
 -----END PGP SIGNATURE-----

Merge tag 'trace-v4.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "While doing tests on tracing over the network, I found that the
  packets were getting corrupted.

  In the process I found three bugs.

  One was the culprit, but the other two scared me. After deeper
  investigation, they were not as major as I thought they were, due to a
  signed compared to an unsigned that prevented a negative number from
  doing actual harm.

  The two bigger bugs:

   - Mask the ring buffer data page length. There are data flags at the
     high bits of the length field. These were not cleared via the
     length function, and the length could return a negative number.
     (Although the number returned was unsigned, but was assigned to a
     signed number) Luckily, this value was compared to PAGE_SIZE which
     is unsigned and kept it from entering the path that could have
     caused damage.

   - Check the page usage before reusing the ring buffer reader page.
     TCP increments the page ref when passing the page off to the
     network. The page is passed back to the ring buffer for use on
     free. But the page could still be in use by the TCP stack.

  Minor bugs:

   - Related to the first bug. No need to clear out the unused ring
     buffer data before sending to user space. It is now done by the
     ring buffer code itself.

   - Reset pointers after free on error path. There were some cases in
     the error path that pointers were freed but not set to NULL, and
     could have them freed again, having a pointer freed twice"

* tag 'trace-v4.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix possible double free on failure of allocating trace buffer
  tracing: Fix crash when it fails to alloc ring buffer
  ring-buffer: Do no reuse reader page if still in use
  tracing: Remove extra zeroing out of the ring buffer page
  ring-buffer: Mask out the info bits when returning buffer page length
2017-12-27 13:06:57 -08:00
Steven Rostedt (VMware)
4397f04575 tracing: Fix possible double free on failure of allocating trace buffer
Jing Xia and Chunyan Zhang reported that on failing to allocate part of the
tracing buffer, memory is freed, but the pointers that point to them are not
initialized back to NULL, and later paths may try to free the freed memory
again. Jing and Chunyan fixed one of the locations that does this, but
missed a spot.

Link: http://lkml.kernel.org/r/20171226071253.8968-1-chunyan.zhang@spreadtrum.com

Cc: stable@vger.kernel.org
Fixes: 737223fbca ("tracing: Consolidate buffer allocation code")
Reported-by: Jing Xia <jing.xia@spreadtrum.com>
Reported-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:21:27 -05:00
Jing Xia
24f2aaf952 tracing: Fix crash when it fails to alloc ring buffer
Double free of the ring buffer happens when it fails to alloc new
ring buffer instance for max_buffer if TRACER_MAX_TRACE is configured.
The root cause is that the pointer is not set to NULL after the buffer
is freed in allocate_trace_buffers(), and the freeing of the ring
buffer is invoked again later if the pointer is not equal to Null,
as:

instance_mkdir()
    |-allocate_trace_buffers()
        |-allocate_trace_buffer(tr, &tr->trace_buffer...)
	|-allocate_trace_buffer(tr, &tr->max_buffer...)

          // allocate fail(-ENOMEM),first free
          // and the buffer pointer is not set to null
        |-ring_buffer_free(tr->trace_buffer.buffer)

       // out_free_tr
    |-free_trace_buffers()
        |-free_trace_buffer(&tr->trace_buffer);

	      //if trace_buffer is not null, free again
	    |-ring_buffer_free(buf->buffer)
                |-rb_free_cpu_buffer(buffer->buffers[cpu])
                    // ring_buffer_per_cpu is null, and
                    // crash in ring_buffer_per_cpu->pages

Link: http://lkml.kernel.org/r/20171226071253.8968-1-chunyan.zhang@spreadtrum.com

Cc: stable@vger.kernel.org
Fixes: 737223fbca ("tracing: Consolidate buffer allocation code")
Signed-off-by: Jing Xia <jing.xia@spreadtrum.com>
Signed-off-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:21:16 -05:00
Steven Rostedt (VMware)
ae415fa4c5 ring-buffer: Do no reuse reader page if still in use
To free the reader page that is allocated with ring_buffer_alloc_read_page(),
ring_buffer_free_read_page() must be called. For faster performance, this
page can be reused by the ring buffer to avoid having to free and allocate
new pages.

The issue arises when the page is used with a splice pipe into the
networking code. The networking code may up the page counter for the page,
and keep it active while sending it is queued to go to the network. The
incrementing of the page ref does not prevent it from being reused in the
ring buffer, and this can cause the page that is being sent out to the
network to be modified before it is sent by reading new data.

Add a check to the page ref counter, and only reuse the page if it is not
being used anywhere else.

Cc: stable@vger.kernel.org
Fixes: 73a757e631 ("ring-buffer: Return reader page back into existing ring buffer")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:21:09 -05:00
Steven Rostedt (VMware)
6b7e633fe9 tracing: Remove extra zeroing out of the ring buffer page
The ring_buffer_read_page() takes care of zeroing out any extra data in the
page that it returns. There's no need to zero it out again from the
consumer. It was removed from one consumer of this function, but
read_buffers_splice_read() did not remove it, and worse, it contained a
nasty bug because of it.

Cc: stable@vger.kernel.org
Fixes: 2711ca237a ("ring-buffer: Move zeroing out excess in page to ring buffer code")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:20:59 -05:00
Steven Rostedt (VMware)
45d8b80c2a ring-buffer: Mask out the info bits when returning buffer page length
Two info bits were added to the "commit" part of the ring buffer data page
when returned to be consumed. This was to inform the user space readers that
events have been missed, and that the count may be stored at the end of the
page.

What wasn't handled, was the splice code that actually called a function to
return the length of the data in order to zero out the rest of the page
before sending it up to user space. These data bits were returned with the
length making the value negative, and that negative value was not checked.
It was compared to PAGE_SIZE, and only used if the size was less than
PAGE_SIZE. Luckily PAGE_SIZE is unsigned long which made the compare an
unsigned compare, meaning the negative size value did not end up causing a
large portion of memory to be randomly zeroed out.

Cc: stable@vger.kernel.org
Fixes: 66a8cb95ed ("ring-buffer: Add place holder recording of dropped events")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:18:10 -05:00
Mathieu Malaterre
76dc6c097d cpu/hotplug: Move inline keyword at the beginning of declaration
Fix non-fatal warnings such as:

kernel/cpu.c:95:1: warning: ‘inline’ is not at beginning of declaration [-Wold-style-declaration]
 static void inline cpuhp_lock_release(bool bringup) { }
 ^~~~~~

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Link: https://lkml.kernel.org/r/20171226140855.16583-1-malat@debian.org
2017-12-27 19:41:04 +01:00
Eric W. Biederman
c0ee554906 pid: Handle failure to allocate the first pid in a pid namespace
With the replacement of the pid bitmap and hashtable with an idr in
alloc_pid started occassionally failing when allocating the first pid
in a pid namespace.  Things were not completely reset resulting in
the first allocated pid getting the number 2 (not 1).  Which
further resulted in ns->proc_mnt not getting set and eventually
causing an oops in proc_flush_task.

Oops: 0000 [#1] SMP
CPU: 2 PID: 6743 Comm: trinity-c117 Not tainted 4.15.0-rc4-think+ #2
RIP: 0010:proc_flush_task+0x8e/0x1b0
RSP: 0018:ffffc9000bbffc40 EFLAGS: 00010286
RAX: 0000000000000001 RBX: 0000000000000001 RCX: 00000000fffffffb
RDX: 0000000000000000 RSI: ffffc9000bbffc50 RDI: 0000000000000000
RBP: ffffc9000bbffc63 R08: 0000000000000000 R09: 0000000000000002
R10: ffffc9000bbffb70 R11: ffffc9000bbffc64 R12: 0000000000000003
R13: 0000000000000000 R14: 0000000000000003 R15: ffff8804c10d7840
FS:  00007f7cb8965700(0000) GS:ffff88050a200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000003e21ae003 CR4: 00000000001606e0
DR0: 00007fb1d6c22000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 ? release_task+0xaf/0x680
 release_task+0xd2/0x680
 ? wait_consider_task+0xb82/0xce0
 wait_consider_task+0xbe9/0xce0
 ? do_wait+0xe1/0x330
 do_wait+0x151/0x330
 kernel_wait4+0x8d/0x150
 ? task_stopped_code+0x50/0x50
 SYSC_wait4+0x95/0xa0
 ? rcu_read_lock_sched_held+0x6c/0x80
 ? syscall_trace_enter+0x2d7/0x340
 ? do_syscall_64+0x60/0x210
 do_syscall_64+0x60/0x210
 entry_SYSCALL64_slow_path+0x25/0x25
RIP: 0033:0x7f7cb82603aa
RSP: 002b:00007ffd60770bc8 EFLAGS: 00000246
 ORIG_RAX: 000000000000003d
RAX: ffffffffffffffda RBX: 00007f7cb6cd4000 RCX: 00007f7cb82603aa
RDX: 000000000000000b RSI: 00007ffd60770bd0 RDI: 0000000000007cca
RBP: 0000000000007cca R08: 00007f7cb8965700 R09: 00007ffd607c7080
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd60770bd0 R14: 00007f7cb6cd4058 R15: 00000000cccccccd
Code: c1 e2 04 44 8b 60 30 48 8b 40 38 44 8b 34 11 48 c7 c2 60 3a f5 81 44 89 e1 4c 8b 68 58 e8 4b b4 77 00 89 44 24 14 48 8d 74 24 10 <49> 8b 7d 00 e8 b9 6a f9 ff 48 85 c0 74 1a 48 89 c7 48 89 44 24
RIP: proc_flush_task+0x8e/0x1b0 RSP: ffffc9000bbffc40
CR2: 0000000000000000
---[ end trace 53d67a6481059862 ]---

Improve the quality of the implementation by resetting the place to
start allocating pids on failure to allocate the first pid.

As improving the quality of the implementation is the goal remove the now
unnecesarry disable_pid_allocations call when we fail to mount proc.

Fixes: 95846ecf9d ("pid: replace pid bitmap implementation with IDR API")
Fixes: 8ef047aaae ("pid namespaces: make alloc_pid(), free_pid() and put_pid() work with struct upid")
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2017-12-23 21:00:09 -06:00
Linus Torvalds
caf9a82657 Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 PTI preparatory patches from Thomas Gleixner:
 "Todays Advent calendar window contains twentyfour easy to digest
  patches. The original plan was to have twenty three matching the date,
  but a late fixup made that moot.

   - Move the cpu_entry_area mapping out of the fixmap into a separate
     address space. That's necessary because the fixmap becomes too big
     with NRCPUS=8192 and this caused already subtle and hard to
     diagnose failures.

     The top most patch is fresh from today and cures a brain slip of
     that tall grumpy german greybeard, who ignored the intricacies of
     32bit wraparounds.

   - Limit the number of CPUs on 32bit to 64. That's insane big already,
     but at least it's small enough to prevent address space issues with
     the cpu_entry_area map, which have been observed and debugged with
     the fixmap code

   - A few TLB flush fixes in various places plus documentation which of
     the TLB functions should be used for what.

   - Rename the SYSENTER stack to CPU_ENTRY_AREA stack as it is used for
     more than sysenter now and keeping the name makes backtraces
     confusing.

   - Prevent LDT inheritance on exec() by moving it to arch_dup_mmap(),
     which is only invoked on fork().

   - Make vysycall more robust.

   - A few fixes and cleanups of the debug_pagetables code. Check
     PAGE_PRESENT instead of checking the PTE for 0 and a cleanup of the
     C89 initialization of the address hint array which already was out
     of sync with the index enums.

   - Move the ESPFIX init to a different place to prepare for PTI.

   - Several code moves with no functional change to make PTI
     integration simpler and header files less convoluted.

   - Documentation fixes and clarifications"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  x86/cpu_entry_area: Prevent wraparound in setup_cpu_entry_area_ptes() on 32bit
  init: Invoke init_espfix_bsp() from mm_init()
  x86/cpu_entry_area: Move it out of the fixmap
  x86/cpu_entry_area: Move it to a separate unit
  x86/mm: Create asm/invpcid.h
  x86/mm: Put MMU to hardware ASID translation in one place
  x86/mm: Remove hard-coded ASID limit checks
  x86/mm: Move the CR3 construction functions to tlbflush.h
  x86/mm: Add comments to clarify which TLB-flush functions are supposed to flush what
  x86/mm: Remove superfluous barriers
  x86/mm: Use __flush_tlb_one() for kernel memory
  x86/microcode: Dont abuse the TLB-flush interface
  x86/uv: Use the right TLB-flush API
  x86/entry: Rename SYSENTER_stack to CPU_ENTRY_AREA_entry_stack
  x86/doc: Remove obvious weirdnesses from the x86 MM layout documentation
  x86/mm/64: Improve the memory map documentation
  x86/ldt: Prevent LDT inheritance on exec
  x86/ldt: Rework locking
  arch, mm: Allow arch_dup_mmap() to fail
  x86/vsyscall/64: Warn and fail vsyscall emulation in NATIVE mode
  ...
2017-12-23 11:53:04 -08:00
Thomas Gleixner
c10e83f598 arch, mm: Allow arch_dup_mmap() to fail
In order to sanitize the LDT initialization on x86 arch_dup_mmap() must be
allowed to fail. Fix up all instances.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirsky <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: dan.j.williams@intel.com
Cc: hughd@google.com
Cc: keescook@google.com
Cc: kirill.shutemov@linux.intel.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-22 20:13:01 +01:00
Linus Torvalds
ead68f2161 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller"
 "What's a holiday weekend without some networking bug fixes? [1]

   1) Fix some eBPF JIT bugs wrt. SKB pointers across helper function
      calls, from Daniel Borkmann.

   2) Fix regression from errata limiting change to marvell PHY driver,
      from Zhao Qiang.

   3) Fix u16 overflow in SCTP, from Xin Long.

   4) Fix potential memory leak during bridge newlink, from Nikolay
      Aleksandrov.

   5) Fix BPF selftest build on s390, from Hendrik Brueckner.

   6) Don't append to cfg80211 automatically generated certs file,
      always write new ones from scratch. From Thierry Reding.

   7) Fix sleep in atomic in mac80211 hwsim, from Jia-Ju Bai.

   8) Fix hang on tg3 MTU change with certain chips, from Brian King.

   9) Add stall detection to arc emac driver and reset chip when this
      happens, from Alexander Kochetkov.

  10) Fix MTU limitng in GRE tunnel drivers, from Xin Long.

  11) Fix stmmac timestamping bug due to mis-shifting of field. From
      Fredrik Hallenberg.

  12) Fix metrics match when deleting an ipv4 route. The kernel sets
      some internal metrics bits which the user isn't going to set when
      it makes the delete request. From Phil Sutter.

  13) mvneta driver loop over RX queues limits on "txq_number" :-) Fix
      from Yelena Krivosheev.

  14) Fix double free and memory corruption in get_net_ns_by_id, from
      Eric W. Biederman.

  15) Flush ipv4 FIB tables in the reverse order. Some tables can share
      their actual backing data, in particular this happens for the MAIN
      and LOCAL tables. We have to kill the LOCAL table first, because
      it uses MAIN's backing memory. Fix from Ido Schimmel.

  16) Several eBPF verifier value tracking fixes, from Edward Cree, Jann
      Horn, and Alexei Starovoitov.

  17) Make changes to ipv6 autoflowlabel sysctl really propagate to
      sockets, unless the socket has set the per-socket value
      explicitly. From Shaohua Li.

  18) Fix leaks and double callback invocations of zerocopy SKBs, from
      Willem de Bruijn"

[1] Is this a trick question? "Relaxing"? "Quiet"? "Fine"? - Linus.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (77 commits)
  skbuff: skb_copy_ubufs must release uarg even without user frags
  skbuff: orphan frags before zerocopy clone
  net: reevalulate autoflowlabel setting after sysctl setting
  openvswitch: Fix pop_vlan action for double tagged frames
  ipv6: Honor specified parameters in fibmatch lookup
  bpf: do not allow root to mangle valid pointers
  selftests/bpf: add tests for recent bugfixes
  bpf: fix integer overflows
  bpf: don't prune branches when a scalar is replaced with a pointer
  bpf: force strict alignment checks for stack pointers
  bpf: fix missing error return in check_stack_boundary()
  bpf: fix 32-bit ALU op verification
  bpf: fix incorrect tracking of register size truncation
  bpf: fix incorrect sign extension in check_alu_op()
  bpf/verifier: fix bounds calculation on BPF_RSH
  ipv4: Fix use-after-free when flushing FIB tables
  s390/qeth: fix error handling in checksum cmd callback
  tipc: remove joining group member from congested list
  selftests: net: Adding config fragment CONFIG_NUMA=y
  nfp: bpf: keep track of the offloaded program
  ...
2017-12-21 15:57:30 -08:00
Alexei Starovoitov
82abbf8d2f bpf: do not allow root to mangle valid pointers
Do not allow root to convert valid pointers into unknown scalars.
In particular disallow:
 ptr &= reg
 ptr <<= reg
 ptr += ptr
and explicitly allow:
 ptr -= ptr
since pkt_end - pkt == length

1.
This minimizes amount of address leaks root can do.
In the future may need to further tighten the leaks with kptr_restrict.

2.
If program has such pointer math it's likely a user mistake and
when verifier complains about it right away instead of many instructions
later on invalid memory access it's easier for users to fix their progs.

3.
when register holding a pointer cannot change to scalar it allows JITs to
optimize better. Like 32-bit archs could use single register for pointers
instead of a pair required to hold 64-bit scalars.

4.
reduces architecture dependent behavior. Since code:
r1 = r10;
r1 &= 0xff;
if (r1 ...)
will behave differently arm64 vs x64 and offloaded vs native.

A significant chunk of ptr mangling was allowed by
commit f1174f77b5 ("bpf/verifier: rework value tracking")
yet some of it was allowed even earlier.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-21 02:26:29 +01:00
Alexei Starovoitov
bb7f0f989c bpf: fix integer overflows
There were various issues related to the limited size of integers used in
the verifier:
 - `off + size` overflow in __check_map_access()
 - `off + reg->off` overflow in check_mem_access()
 - `off + reg->var_off.value` overflow or 32-bit truncation of
   `reg->var_off.value` in check_mem_access()
 - 32-bit truncation in check_stack_boundary()

Make sure that any integer math cannot overflow by not allowing
pointer math with large values.

Also reduce the scope of "scalar op scalar" tracking.

Fixes: f1174f77b5 ("bpf/verifier: rework value tracking")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-21 02:15:41 +01:00
Jann Horn
179d1c5602 bpf: don't prune branches when a scalar is replaced with a pointer
This could be made safe by passing through a reference to env and checking
for env->allow_ptr_leaks, but it would only work one way and is probably
not worth the hassle - not doing it will not directly lead to program
rejection.

Fixes: f1174f77b5 ("bpf/verifier: rework value tracking")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-21 02:15:41 +01:00
Jann Horn
a5ec6ae161 bpf: force strict alignment checks for stack pointers
Force strict alignment checks for stack pointers because the tracking of
stack spills relies on it; unaligned stack accesses can lead to corruption
of spilled registers, which is exploitable.

Fixes: f1174f77b5 ("bpf/verifier: rework value tracking")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-21 02:15:41 +01:00
Jann Horn
ea25f914dc bpf: fix missing error return in check_stack_boundary()
Prevent indirect stack accesses at non-constant addresses, which would
permit reading and corrupting spilled pointers.

Fixes: f1174f77b5 ("bpf/verifier: rework value tracking")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-21 02:15:41 +01:00
Jann Horn
468f6eafa6 bpf: fix 32-bit ALU op verification
32-bit ALU ops operate on 32-bit values and have 32-bit outputs.
Adjust the verifier accordingly.

Fixes: f1174f77b5 ("bpf/verifier: rework value tracking")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-21 02:15:41 +01:00
Jann Horn
0c17d1d2c6 bpf: fix incorrect tracking of register size truncation
Properly handle register truncation to a smaller size.

The old code first mirrors the clearing of the high 32 bits in the bitwise
tristate representation, which is correct. But then, it computes the new
arithmetic bounds as the intersection between the old arithmetic bounds and
the bounds resulting from the bitwise tristate representation. Therefore,
when coerce_reg_to_32() is called on a number with bounds
[0xffff'fff8, 0x1'0000'0007], the verifier computes
[0xffff'fff8, 0xffff'ffff] as bounds of the truncated number.
This is incorrect: The truncated number could also be in the range [0, 7],
and no meaningful arithmetic bounds can be computed in that case apart from
the obvious [0, 0xffff'ffff].

Starting with v4.14, this is exploitable by unprivileged users as long as
the unprivileged_bpf_disabled sysctl isn't set.

Debian assigned CVE-2017-16996 for this issue.

v2:
 - flip the mask during arithmetic bounds calculation (Ben Hutchings)
v3:
 - add CVE number (Ben Hutchings)

Fixes: b03c9f9fdc ("bpf/verifier: track signed and unsigned min/max values")
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-21 02:15:41 +01:00
Jann Horn
95a762e2c8 bpf: fix incorrect sign extension in check_alu_op()
Distinguish between
BPF_ALU64|BPF_MOV|BPF_K (load 32-bit immediate, sign-extended to 64-bit)
and BPF_ALU|BPF_MOV|BPF_K (load 32-bit immediate, zero-padded to 64-bit);
only perform sign extension in the first case.

Starting with v4.14, this is exploitable by unprivileged users as long as
the unprivileged_bpf_disabled sysctl isn't set.

Debian assigned CVE-2017-16995 for this issue.

v3:
 - add CVE number (Ben Hutchings)

Fixes: 484611357c ("bpf: allow access into map value arrays")
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-21 02:15:41 +01:00
Edward Cree
4374f256ce bpf/verifier: fix bounds calculation on BPF_RSH
Incorrect signed bounds were being computed.
If the old upper signed bound was positive and the old lower signed bound was
negative, this could cause the new upper signed bound to be too low,
leading to security issues.

Fixes: b03c9f9fdc ("bpf/verifier: track signed and unsigned min/max values")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Edward Cree <ecree@solarflare.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
[jannh@google.com: changed description to reflect bug impact]
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-21 02:15:41 +01:00
Tejun Heo
74d0833c65 cgroup: fix css_task_iter crash on CSS_TASK_ITER_PROC
While teaching css_task_iter to handle skipping over tasks which
aren't group leaders, bc2fb7ed08 ("cgroup: add @flags to
css_task_iter_start() and implement CSS_TASK_ITER_PROCS") introduced a
silly bug.

CSS_TASK_ITER_PROCS is implemented by repeating
css_task_iter_advance() while the advanced cursor is pointing to a
non-leader thread.  However, the cursor variable, @l, wasn't updated
when the iteration has to advance to the next css_set and the
following repetition would operate on the terminal @l from the
previous iteration which isn't pointing to a valid task leading to
oopses like the following or infinite looping.

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000254
  IP: __task_pid_nr_ns+0xc7/0xf0
  PGD 0 P4D 0
  Oops: 0000 [#1] SMP
  ...
  CPU: 2 PID: 1 Comm: systemd Not tainted 4.14.4-200.fc26.x86_64 #1
  Hardware name: System manufacturer System Product Name/PRIME B350M-A, BIOS 3203 11/09/2017
  task: ffff88c4baee8000 task.stack: ffff96d5c3158000
  RIP: 0010:__task_pid_nr_ns+0xc7/0xf0
  RSP: 0018:ffff96d5c315bd50 EFLAGS: 00010206
  RAX: 0000000000000000 RBX: ffff88c4b68c6000 RCX: 0000000000000250
  RDX: ffffffffa5e47960 RSI: 0000000000000000 RDI: ffff88c490f6ab00
  RBP: ffff96d5c315bd50 R08: 0000000000001000 R09: 0000000000000005
  R10: ffff88c4be006b80 R11: ffff88c42f1b8004 R12: ffff96d5c315bf18
  R13: ffff88c42d7dd200 R14: ffff88c490f6a510 R15: ffff88c4b68c6000
  FS:  00007f9446f8ea00(0000) GS:ffff88c4be680000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000254 CR3: 00000007f956f000 CR4: 00000000003406e0
  Call Trace:
   cgroup_procs_show+0x19/0x30
   cgroup_seqfile_show+0x4c/0xb0
   kernfs_seq_show+0x21/0x30
   seq_read+0x2ec/0x3f0
   kernfs_fop_read+0x134/0x180
   __vfs_read+0x37/0x160
   ? security_file_permission+0x9b/0xc0
   vfs_read+0x8e/0x130
   SyS_read+0x55/0xc0
   entry_SYSCALL_64_fastpath+0x1a/0xa5
  RIP: 0033:0x7f94455f942d
  RSP: 002b:00007ffe81ba2d00 EFLAGS: 00000293 ORIG_RAX: 0000000000000000
  RAX: ffffffffffffffda RBX: 00005574e2233f00 RCX: 00007f94455f942d
  RDX: 0000000000001000 RSI: 00005574e2321a90 RDI: 000000000000002b
  RBP: 0000000000000000 R08: 00005574e2321a90 R09: 00005574e231de60
  R10: 00007f94458c8b38 R11: 0000000000000293 R12: 00007f94458c8ae0
  R13: 00007ffe81ba3800 R14: 0000000000000000 R15: 00005574e2116560
  Code: 04 74 0e 89 f6 48 8d 04 76 48 8d 04 c5 f0 05 00 00 48 8b bf b8 05 00 00 48 01 c7 31 c0 48 8b 0f 48 85 c9 74 18 8b b2 30 08 00 00 <3b> 71 04 77 0d 48 c1 e6 05 48 01 f1 48 3b 51 38 74 09 5d c3 8b
  RIP: __task_pid_nr_ns+0xc7/0xf0 RSP: ffff96d5c315bd50

Fix it by moving the initialization of the cursor below the repeat
label.  While at it, rename it to @next for readability.

Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes: bc2fb7ed08 ("cgroup: add @flags to css_task_iter_start() and implement CSS_TASK_ITER_PROCS")
Cc: stable@vger.kernel.org # v4.14+
Reported-by: Laura Abbott <labbott@redhat.com>
Reported-by: Bronek Kozicki <brok@incorrekt.com>
Reported-by: George Amanakis <gamanakis@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-12-20 07:09:19 -08:00
Prateek Sood
116d2f7496 cgroup: Fix deadlock in cpu hotplug path
Deadlock during cgroup migration from cpu hotplug path when a task T is
being moved from source to destination cgroup.

kworker/0:0
cpuset_hotplug_workfn()
   cpuset_hotplug_update_tasks()
      hotplug_update_tasks_legacy()
        remove_tasks_in_empty_cpuset()
          cgroup_transfer_tasks() // stuck in iterator loop
            cgroup_migrate()
              cgroup_migrate_add_task()

In cgroup_migrate_add_task() it checks for PF_EXITING flag of task T.
Task T will not migrate to destination cgroup. css_task_iter_start()
will keep pointing to task T in loop waiting for task T cg_list node
to be removed.

Task T
do_exit()
  exit_signals() // sets PF_EXITING
  exit_task_namespaces()
    switch_task_namespaces()
      free_nsproxy()
        put_mnt_ns()
          drop_collected_mounts()
            namespace_unlock()
              synchronize_rcu()
                _synchronize_rcu_expedited()
                  schedule_work() // on cpu0 low priority worker pool
                  wait_event() // waiting for work item to execute

Task T inserted a work item in the worklist of cpu0 low priority
worker pool. It is waiting for expedited grace period work item
to execute. This work item will only be executed once kworker/0:0
complete execution of cpuset_hotplug_workfn().

kworker/0:0 ==> Task T ==>kworker/0:0

In case of PF_EXITING task being migrated from source to destination
cgroup, migrate next available task in source cgroup.

Signed-off-by: Prateek Sood <prsood@codeaurora.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-12-19 05:38:47 -08:00
David S. Miller
b36025b19a Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2017-12-17

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Fix a corner case in generic XDP where we have non-linear skbs
   but enough tailroom in the skb to not miss to linearizing there,
   from Song.

2) Fix BPF JIT bugs in s390x and ppc64 to not recache skb data when
   BPF context is not skb, from Daniel.

3) Fix a BPF JIT bug in sparc64 where recaching skb data after helper
   call would use the wrong register for the skb, from Daniel.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-18 10:49:22 -05:00
Paul E. McKenney
bf29cb238d sched/isolation: Make CONFIG_NO_HZ_FULL select CONFIG_CPU_ISOLATION
CONFIG_NO_HZ_FULL doesn't make sense without CONFIG_CPU_ISOLATION. In
fact enabling the first without the second is a regression as nohz_full=
boot parameter gets silently ignored.

Besides this unnatural combination hangs RCU gp kthread when running
rcutorture for reasons that are not yet fully understood:

	rcu_preempt kthread starved for 9974 jiffies! g4294967208
	+c4294967207 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x402 ->cpu=0
	rcu_preempt     I 7464     8      2 0x80000000
	Call Trace:
		__schedule+0x493/0x620
		schedule+0x24/0x40
		schedule_timeout+0x330/0x3b0
		? preempt_count_sub+0xea/0x140
		? collect_expired_timers+0xb0/0xb0
		rcu_gp_kthread+0x6bf/0xef0

This commit therefore makes NO_HZ_FULL select CPU_ISOLATION, which
prevents all these bad behaviours.

Reported-by: kernel test robot <xiaolong.ye@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <kernellwp@gmail.com>
Fixes: 5c4991e24c ("sched/isolation: Split out new CONFIG_CPU_ISOLATION=y config from CONFIG_NO_HZ_FULL")
Link: http://lkml.kernel.org/r/1513275507-29200-2-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-18 13:46:42 +01:00
Linus Torvalds
2ffb448ccb Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fix from Thomas Gleixner:
 "A single bugfix which prevents arbitrary sigev_notify values in
  posix-timers"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  posix-timer: Properly check sigevent->sigev_notify
2017-12-17 13:48:50 -08:00
Will Deacon
3382290ed2 locking/barriers: Convert users of lockless_dereference() to READ_ONCE()
[ Note, this is a Git cherry-pick of the following commit:

    506458efaf ("locking/barriers: Convert users of lockless_dereference() to READ_ONCE()")

  ... for easier x86 PTI code testing and back-porting. ]

READ_ONCE() now has an implicit smp_read_barrier_depends() call, so it
can be used instead of lockless_dereference() without any change in
semantics.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1508840570-22169-4-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-17 13:57:15 +01:00
Linus Torvalds
7a3c296ae0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Clamp timeouts to INT_MAX in conntrack, from Jay Elliot.

 2) Fix broken UAPI for BPF_PROG_TYPE_PERF_EVENT, from Hendrik
    Brueckner.

 3) Fix locking in ieee80211_sta_tear_down_BA_sessions, from Johannes
    Berg.

 4) Add missing barriers to ptr_ring, from Michael S. Tsirkin.

 5) Don't advertise gigabit in sh_eth when not available, from Thomas
    Petazzoni.

 6) Check network namespace when delivering to netlink taps, from Kevin
    Cernekee.

 7) Kill a race in raw_sendmsg(), from Mohamed Ghannam.

 8) Use correct address in TCP md5 lookups when replying to an incoming
    segment, from Christoph Paasch.

 9) Add schedule points to BPF map alloc/free, from Eric Dumazet.

10) Don't allow silly mtu values to be used in ipv4/ipv6 multicast, also
    from Eric Dumazet.

11) Fix SKB leak in tipc, from Jon Maloy.

12) Disable MAC learning on OVS ports of mlxsw, from Yuval Mintz.

13) SKB leak fix in skB_complete_tx_timestamp(), from Willem de Bruijn.

14) Add some new qmi_wwan device IDs, from Daniele Palmas.

15) Fix static key imbalance in ingress qdisc, from Jiri Pirko.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (76 commits)
  net: qcom/emac: Reduce timeout for mdio read/write
  net: sched: fix static key imbalance in case of ingress/clsact_init error
  net: sched: fix clsact init error path
  ip_gre: fix wrong return value of erspan_rcv
  net: usb: qmi_wwan: add Telit ME910 PID 0x1101 support
  pkt_sched: Remove TC_RED_OFFLOADED from uapi
  net: sched: Move to new offload indication in RED
  net: sched: Add TCA_HW_OFFLOAD
  net: aquantia: Increment driver version
  net: aquantia: Fix typo in ethtool statistics names
  net: aquantia: Update hw counters on hw init
  net: aquantia: Improve link state and statistics check interval callback
  net: aquantia: Fill in multicast counter in ndev stats from hardware
  net: aquantia: Fill ndev stat couters from hardware
  net: aquantia: Extend stat counters to 64bit values
  net: aquantia: Fix hardware DMA stream overload on large MRRS
  net: aquantia: Fix actual speed capabilities reporting
  sock: free skb in skb_complete_tx_timestamp on error
  s390/qeth: update takeover IPs after configuration change
  s390/qeth: lock IP table while applying takeover changes
  ...
2017-12-15 13:08:37 -08:00
Linus Torvalds
1f76a75561 Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Ingo Molnar:
 "Misc fixes:

   - Fix a S390 boot hang that was caused by the lock-break logic.
     Remove lock-break to begin with, as review suggested it was
     unreasonably fragile and our confidence in its continued good
     health is lower than our confidence in its removal.

   - Remove the lockdep cross-release checking code for now, because of
     unresolved false positive warnings. This should make lockdep work
     well everywhere again.

   - Get rid of the final (and single) ACCESS_ONCE() straggler and
     remove the API from v4.15.

   - Fix a liblockdep build warning"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tools/lib/lockdep: Add missing declaration of 'pr_cont()'
  checkpatch: Remove ACCESS_ONCE() warning
  compiler.h: Remove ACCESS_ONCE()
  tools/include: Remove ACCESS_ONCE()
  tools/perf: Convert ACCESS_ONCE() to READ_ONCE()
  locking/lockdep: Remove the cross-release locking checks
  locking/core: Remove break_lock field when CONFIG_GENERIC_LOCKBREAK=y
  locking/core: Fix deadlock during boot on systems with GENERIC_LOCKBREAK
2017-12-15 11:44:59 -08:00
Linus Torvalds
a58653cc1e Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Two fixes: a crash fix for an ARM SoC platform, and kernel-doc
  warnings fixes"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/rt: Do not pull from current CPU if only one CPU to pull
  sched/core: Fix kernel-doc warnings after code movement
2017-12-15 11:40:24 -08:00
Daniel Borkmann
04514d1322 bpf: guarantee r1 to be ctx in case of bpf_helper_changes_pkt_data
Some JITs don't cache skb context on stack in prologue, so when
LD_ABS/IND is used and helper calls yield bpf_helper_changes_pkt_data()
as true, then they temporarily save/restore skb pointer. However,
the assumption that skb always has to be in r1 is a bit of a
gamble. Right now it turned out to be true for all helpers listed
in bpf_helper_changes_pkt_data(), but lets enforce that from verifier
side, so that we make this a guarantee and bail out if the func
proto is misconfigured in future helpers.

In case of BPF helper calls from cBPF, bpf_helper_changes_pkt_data()
is completely unrelevant here (since cBPF is context read-only) and
therefore always false.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-15 09:19:35 -08:00
Steven Rostedt
f73c52a5bc sched/rt: Do not pull from current CPU if only one CPU to pull
Daniel Wagner reported a crash on the BeagleBone Black SoC.

This is a single CPU architecture, and does not have a functional
arch_send_call_function_single_ipi() implementation which can crash
the kernel if that is called.

As it only has one CPU, it shouldn't be called, but if the kernel is
compiled for SMP, the push/pull RT scheduling logic now calls it for
irq_work if the one CPU is overloaded, it can use that function to call
itself and crash the kernel.

Ideally, we should disable the SCHED_FEAT(RT_PUSH_IPI) if the system
only has a single CPU. But SCHED_FEAT is a constant if sched debugging
is turned off. Another fix can also be used, and this should also help
with normal SMP machines. That is, do not initiate the pull code if
there's only one RT overloaded CPU, and that CPU happens to be the
current CPU that is scheduling in a lower priority task.

Even on a system with many CPUs, if there's many RT tasks waiting to
run on a single CPU, and that CPU schedules in another RT task of lower
priority, it will initiate the PULL logic in case there's a higher
priority RT task on another CPU that is waiting to run. But if there is
no other CPU with waiting RT tasks, it will initiate the RT pull logic
on itself (as it still has RT tasks waiting to run). This is a wasted
effort.

Not only does this help with SMP code where the current CPU is the only
one with RT overloaded tasks, it should also solve the issue that
Daniel encountered, because it will prevent the PULL logic from
executing, as there's only one CPU on the system, and the check added
here will cause it to exit the RT pull code.

Reported-by: Daniel Wagner <wagi@monom.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-rt-users <linux-rt-users@vger.kernel.org>
Cc: stable@vger.kernel.org
Fixes: 4bdced5c9 ("sched/rt: Simplify the IPI based RT balancing logic")
Link: http://lkml.kernel.org/r/20171202130454.4cbbfe8d@vmware.local.home
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-15 16:28:02 +01:00
Arnd Bergmann
50034ed496 cgroup: use strlcpy() instead of strscpy() to avoid spurious warning
As long as cft->name is guaranteed to be NUL-terminated, using strlcpy() would
work just as well and avoid that warning, so the change below could be folded
into that commit.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-12-15 05:09:47 -08:00
Thomas Gleixner
cef31d9af9 posix-timer: Properly check sigevent->sigev_notify
timer_create() specifies via sigevent->sigev_notify the signal delivery for
the new timer. The valid modes are SIGEV_NONE, SIGEV_SIGNAL, SIGEV_THREAD
and (SIGEV_SIGNAL | SIGEV_THREAD_ID).

The sanity check in good_sigevent() is only checking the valid combination
for the SIGEV_THREAD_ID bit, i.e. SIGEV_SIGNAL, but if SIGEV_THREAD_ID is
not set it accepts any random value.

This has no real effects on the posix timer and signal delivery code, but
it affects show_timer() which handles the output of /proc/$PID/timers. That
function uses a string array to pretty print sigev_notify. The access to
that array has no bound checks, so random sigev_notify cause access beyond
the array bounds.

Add proper checks for the valid notify modes and remove the SIGEV_THREAD_ID
masking from various code pathes as SIGEV_NONE can never be set in
combination with SIGEV_THREAD_ID.

Reported-by: Eric Biggers <ebiggers3@gmail.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: stable@vger.kernel.org
2017-12-15 11:08:40 +01:00
Linus Torvalds
0424378781 Various fix ups.
- Comment fixes
  - Build fix
  - Better memory alloction (don't use NR_CPUS)
  - Configuration fix
  - Build warning fix
  - Enhanced callback parameter (to simplify users of trace hooks)
  - Give up on stack tracing when RCU isn't watching (it's a lost cause)
 -----BEGIN PGP SIGNATURE-----
 
 iQHIBAABCgAyFiEEPm6V/WuN2kyArTUe1a05Y9njSUkFAlozKm0UHHJvc3RlZHRA
 Z29vZG1pcy5vcmcACgkQ1a05Y9njSUmhXwv7BEY923K3Nl3qC6LeYmNyrZ4g1PsD
 nbZ+ZjU3KlMPugGbnJCJbfsS0utUp2Wd9gHT32O4BUf0/Pxjo3utXvkzRQJ3SwHT
 X7QhXROkicAKRFrPxj0BaiLexC+yJR23wGp2YUVHLO4Aa/ptN8BJvH22+eDpsCLc
 f1DWJdvdbyPBUeoHNKevjvccsUYMlnBfe1jhJ9nRWHnq1axGV3bllcd6v4T07LgK
 LO28Krp4/V3tVN9Sq6jBoGTrULf5O1xtuBDVtANeXdha1oMUTYr4TUzTuOQxFgNu
 sCIpUWTKu+PNGmU5bhlryb20C2+PveE4EMK0InVVlqrhYJ/XjXFyRaZYYkM2NAKq
 XmeHVjMfc6Wmrd/nepuaTZvGGrK2kK/pCX/XuQthKKjAU6rO5X+FfGiSGodLPIYB
 1m+QvfX8Re2IJkswm3lS68LKtG7SnjcSB9sY6PhVe6C6oP2ya2O1hthJ+TkrfNbc
 lhE5HzfCJZ9ujSjcQoUGwjrhnIezQX4KnfJZ
 =WdMQ
 -----END PGP SIGNATURE-----

Merge tag 'trace-v4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Various fix-ups:

   - comment fixes

   - build fix

   - better memory alloction (don't use NR_CPUS)

   - configuration fix

   - build warning fix

   - enhanced callback parameter (to simplify users of trace hooks)

   - give up on stack tracing when RCU isn't watching (it's a lost
     cause)"

* tag 'trace-v4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Have stack trace not record if RCU is not watching
  tracing: Pass export pointer as argument to ->write()
  ring-buffer: Remove unused function __rb_data_page_index()
  tracing: make PREEMPTIRQ_EVENTS depend on TRACING
  tracing: Allocate mask_str buffer dynamically
  tracing: always define trace_{irq,preempt}_{enable_disable}
  tracing: Fix code comments in trace.c
2017-12-14 18:21:33 -08:00
Steven Rostedt (VMware)
b00d607bb1 tracing: Have stack trace not record if RCU is not watching
The stack tracer records a stack dump whenever it sees a stack usage that is
more than what it ever saw before. This can happen at any function that is
being traced. If it happens when the CPU is going idle (or other strange
locations), RCU may not be watching, and in this case, the recording of the
stack trace will trigger a warning. There's been lots of efforts to make
hacks to allow stack tracing to proceed even if RCU is not watching, but
this only causes more issues to appear. Simply do not trace a stack if RCU
is not watching. It probably isn't a bad stack anyway.

Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-14 20:48:22 -05:00
Sudip Mukherjee
7c2c11b208 arch: define weak abort()
gcc toggle -fisolate-erroneous-paths-dereference (default at -O2
onwards) isolates faulty code paths such as null pointer access, divide
by zero etc.  If gcc port doesnt implement __builtin_trap, an abort() is
generated which causes kernel link error.

In this case, gcc is generating abort due to 'divide by zero' in
lib/mpi/mpih-div.c.

Currently 'frv' and 'arc' are failing.  Previously other arch was also
broken like m32r was fixed by commit d22e3d69ee ("m32r: fix build
failure").

Let's define this weak function which is common for all arch and fix the
problem permanently.  We can even remove the arch specific 'abort' after
this is done.

Link: http://lkml.kernel.org/r/1513118956-8718-1-git-send-email-sudipm.mukherjee@gmail.com
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-12-14 16:00:49 -08:00
Thiago Rafael Becker
bdcf0a423e kernel: make groups_sort calling a responsibility group_info allocators
In testing, we found that nfsd threads may call set_groups in parallel
for the same entry cached in auth.unix.gid, racing in the call of
groups_sort, corrupting the groups for that entry and leading to
permission denials for the client.

This patch:
 - Make groups_sort globally visible.
 - Move the call to groups_sort to the modifiers of group_info
 - Remove the call to groups_sort from set_groups

Link: http://lkml.kernel.org/r/20171211151420.18655-1-thiago.becker@gmail.com
Signed-off-by: Thiago Rafael Becker <thiago.becker@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: NeilBrown <neilb@suse.com>
Acked-by: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-12-14 16:00:49 -08:00
Dmitry Vyukov
689d77f001 kcov: fix comparison callback signature
Fix a silly copy-paste bug.  We truncated u32 args to u16.

Link: http://lkml.kernel.org/r/20171207101134.107168-1-dvyukov@google.com
Fixes: ded97d2c2b ("kcov: support comparison operands collection")
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Cc: syzkaller@googlegroups.com
Cc: Alexander Potapenko <glider@google.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-12-14 16:00:48 -08:00
Wolffhardt Schwabe
8b2770a4e1 fix typo in assignment of fs default overflow gid
The patch remains without practical effect since both macros carry
identical values.  Still, it might become a problem in the future if
(for whatever reason) the default overflow uid and gid differ.  The
DEFAULT_FS_OVERFLOWGID macro was previously unused.

Signed-off-by: Wolffhardt Schwabe <wolffhardt.schwabe@fau.de>
Signed-off-by: Anatoliy Cherepantsev <anatoliy.cherepantsev@fau.de>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2017-12-14 16:01:45 -06:00
Eric Dumazet
9147efcbe0 bpf: add schedule points to map alloc/free
While using large percpu maps, htab_map_alloc() can hold
cpu for hundreds of ms.

This patch adds cond_resched() calls to percpu alloc/free
call sites, all running in process context.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-12 15:27:22 -08:00
Daniel Borkmann
283ca526a9 bpf: fix corruption on concurrent perf_event_output calls
When tracing and networking programs are both attached in the
system and both use event-output helpers that eventually call
into perf_event_output(), then we could end up in a situation
where the tracing attached program runs in user context while
a cls_bpf program is triggered on that same CPU out of softirq
context.

Since both rely on the same per-cpu perf_sample_data, we could
potentially corrupt it. This can only ever happen in a combination
of the two types; all tracing programs use a bpf_prog_active
counter to bail out in case a program is already running on
that CPU out of a different context. XDP and cls_bpf programs
by themselves don't have this issue as they run in the same
context only. Therefore, split both perf_sample_data so they
cannot be accessed from each other.

Fixes: 20b9d7ac48 ("bpf: avoid excessive stack usage for perf_sample_data")
Reported-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Song Liu <songliubraving@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-12 09:51:12 -08:00
Ma Shimiao
e7fd37ba12 cgroup: avoid copying strings longer than the buffers
cgroup root name and file name have max length limit, we should
avoid copying longer name than that to the name.

tj: minor update to $SUBJ.

Signed-off-by: Ma Shimiao <mashimiao.fnst@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-12-12 07:53:29 -08:00
Ingo Molnar
e966eaeeb6 locking/lockdep: Remove the cross-release locking checks
This code (CONFIG_LOCKDEP_CROSSRELEASE=y and CONFIG_LOCKDEP_COMPLETIONS=y),
while it found a number of old bugs initially, was also causing too many
false positives that caused people to disable lockdep - which is arguably
a worse overall outcome.

If we disable cross-release by default but keep the code upstream then
in practice the most likely outcome is that we'll allow the situation
to degrade gradually, by allowing entropy to introduce more and more
false positives, until it overwhelms maintenance capacity.

Another bad side effect was that people were trying to work around
the false positives by uglifying/complicating unrelated code. There's
a marked difference between annotating locking operations and
uglifying good code just due to bad lock debugging code ...

This gradual decrease in quality happened to a number of debugging
facilities in the kernel, and lockdep is pretty complex already,
so we cannot risk this outcome.

Either cross-release checking can be done right with no false positives,
or it should not be included in the upstream kernel.

( Note that it might make sense to maintain it out of tree and go through
  the false positives every now and then and see whether new bugs were
  introduced. )

Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-12 12:38:51 +01:00
Will Deacon
d89c70356a locking/core: Remove break_lock field when CONFIG_GENERIC_LOCKBREAK=y
When CONFIG_GENERIC_LOCKBEAK=y, locking structures grow an extra int ->break_lock
field which is used to implement raw_spin_is_contended() by setting the field
to 1 when waiting on a lock and clearing it to zero when holding a lock.
However, there are a few problems with this approach:

  - There is a write-write race between a CPU successfully taking the lock
    (and subsequently writing break_lock = 0) and a waiter waiting on
    the lock (and subsequently writing break_lock = 1). This could result
    in a contended lock being reported as uncontended and vice-versa.

  - On machines with store buffers, nothing guarantees that the writes
    to break_lock are visible to other CPUs at any particular time.

  - READ_ONCE/WRITE_ONCE are not used, so the field is potentially
    susceptible to harmful compiler optimisations,

Consequently, the usefulness of this field is unclear and we'd be better off
removing it and allowing architectures to implement raw_spin_is_contended() by
providing a definition of arch_spin_is_contended(), as they can when
CONFIG_GENERIC_LOCKBREAK=n.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1511894539-7988-3-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-12 11:24:01 +01:00
Will Deacon
f87f3a328d locking/core: Fix deadlock during boot on systems with GENERIC_LOCKBREAK
Commit:

  a8a217c221 ("locking/core: Remove {read,spin,write}_can_lock()")

removed the definition of raw_spin_can_lock(), causing the GENERIC_LOCKBREAK
spin_lock() routines to poll the ->break_lock field when waiting on a lock.

This has been reported to cause a deadlock during boot on s390, because
the ->break_lock field is also set by the waiters, and can potentially
remain set indefinitely if no other CPUs come in to take the lock after
it has been released.

This patch removes the explicit spinning on ->break_lock from the waiters,
instead relying on the outer trylock() operation to determine when the
lock is available.

Reported-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Tested-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: a8a217c221 ("locking/core: Remove {read,spin,write}_can_lock()")
Link: http://lkml.kernel.org/r/1511894539-7988-2-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-12 11:24:01 +01:00
Linus Torvalds
085bec853a Merge branch 'for-4.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:

 - Prateek posted a couple patches to fix a deadlock involving cpuset
   and workqueue. It unfortunately caused a different deadlock and the
   recent workqueue hotplug simplification removed the original
   deadlock, so Prateek's two patches are reverted for now.

 - The new stat code was missing u64_stats initialization. Fixed.

 - Doc and other misc changes

* 'for-4.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: add warning about RT not being supported on cgroup2
  Revert "cgroup/cpuset: remove circular dependency deadlock"
  Revert "cpuset: Make cpuset hotplug synchronous"
  cgroup: properly init u64_stats
  debug cgroup: use task_css_set instead of rcu_dereference
  cpuset: Make cpuset hotplug synchronous
  cgroup/cpuset: remove circular dependency deadlock
2017-12-11 17:10:05 -08:00
Linus Torvalds
72dd379e67 Merge branch 'for-4.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue fixes from Tejun Heo:

 - Lai's hotplug simplifications inadvertently fix a possible deadlock
   involving cpuset and workqueue

 - CPU isolation fix which was reverted due to the changes in the
   housekeeping code resurrected

 - A trivial unused include removal

* 'for-4.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: remove unneeded kallsyms include
  workqueue/hotplug: remove the workaround in rebind_workers()
  workqueue/hotplug: simplify workqueue_offline_cpu()
  workqueue: respect isolated cpus when queueing an unbound work
  main: kernel_start: move housekeeping_init() before workqueue_init_early()
2017-12-11 17:07:26 -08:00
Paul E. McKenney
1dfa55e019 Merge branches 'cond_resched.2017.12.04a', 'dyntick.2017.11.28a', 'fixes.2017.12.11a', 'srbd.2017.12.05a' and 'torture.2017.12.11a' into HEAD
cond_resched.2017.12.04a: Convert cond_resched_rcu_qs() to cond_resched()
dyntick.2017.11.28a: Make RCU dynticks handle interrupts from NMI
fixes.2017.12.11a: Miscellaneous fixes
srbd.2017.12.05a: Remove now-redundant smp_read_barrier_depends()
torture.2017.12.11a: Torture-testing update
2017-12-11 09:21:58 -08:00
Paul E. McKenney
29d3939084 torture: Save a line in stutter_wait(): while -> for
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-12-11 09:18:30 -08:00
Paul E. McKenney
a2f2577d96 torture: Eliminate torture_runnable and perf_runnable
The purpose of torture_runnable is to allow rcutorture and locktorture
to be started and stopped via sysfs when they are built into the kernel
(as in not compiled as loadable modules).  However, the 0444 permissions
for both instances of torture_runnable prevent this use case from ever
being put into practice.  Given that there have been no complaints
about this deficiency, it is reasonable to conclude that no one actually
makes use of this sysfs capability.  The perf_runnable module parameter
for rcuperf is in the same situation.

This commit therefore removes both torture_runnable instances as well
as perf_runnable.

Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-12-11 09:18:29 -08:00
Paul E. McKenney
4ced3314fd torture: Make stutter less vulnerable to compilers and races
The stutter_wait() function repeatedly fetched stutter_pause_test, and
should really just fetch it once on each pass.  The races should be
harmless, but why have the races?  Also, the whole point of the value
"2" for stutter_pause_test is to get everyone to start at very nearly
the same time, but the value "2" was the first jiffy of the stutter
rather than the last jiffy of the stutter.

This commit rearranges the code to be more sensible.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-12-11 09:18:29 -08:00
Davidlohr Bueso
2ce77d16db locking/locktorture: Fix num reader/writer corner cases
Things can explode for locktorture if the user does combinations
of nwriters_stress=0 nreaders_stress=0. Fix this by not assuming
we always want to torture writer threads.

Reported-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Jeremy Linton <jeremy.linton@arm.com>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
2017-12-11 09:18:28 -08:00
Davidlohr Bueso
f2f762608f locking/locktorture: Fix rwsem reader_delay
We should account for nreader threads, not writers in this
callback. Could even trigger a div by 0 if the user explicitly
disables writers.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-12-11 09:18:28 -08:00
Paul E. McKenney
e8302739aa rcutorture: Preempt RCU-preempt readers more vigorously
This commit attempts to make a very rare rcutorture failure happen
more often by increasing the fraction of RCU-preempt read-side critical
sections that are preempted.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-12-11 09:18:22 -08:00
Paul E. McKenney
cc1321c96f torture: Reduce #ifdefs for preempt_schedule()
This commit adds a torture_preempt_schedule() that is nothingness
in !PREEMPT builds and is preempt_schedule() otherwise.  Then
torture_preempt_schedule() is used to eliminate several ugly #ifdefs,
both in rcutorture and in locktorture.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-12-11 09:18:22 -08:00
Rakib Mullick
84b12b752f rcu: Remove have_rcu_nocb_mask from tree_plugin.h
Currently have_rcu_nocb_mask is used to avoid double allocation of
rcu_nocb_mask during boot up. Due to different representation of
cpumask_var_t on different kernel config CPUMASK=y(or n) it was okay.
But now we have a helper cpumask_available(), which can be utilized
to check whether rcu_nocb_mask has been allocated or not without using
a variable.

Removing the variable also reduces vmlinux size.

Unpatched version:
text	   data	    bss	    dec	    hex	filename
13050393	7852470	14543408	35446271	21cddff	vmlinux

Patched version:
 text	   data	    bss	    dec	    hex	filename
13050390	7852438	14543408	35446236	21cdddc	vmlinux

Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-12-11 09:17:40 -08:00
Paul E. McKenney
efd88b02bb rcu: Add comment giving debug strategy for double call_rcu()
The following statement has for some reason proven non-intuitive:

	WARN_ON_ONCE(rcu_segcblist_empty(&rdp->cblist) != (count == 0));

This commit therefore adds a comment that states that this warning
usually triggers in response to a double call_rcu(), which is sort
of like a double free.  The comment also suggests building with
CONFIG_DEBUG_OBJECTS_RCU_HEAD=y to track down the double call_rcu().

Reported-by: David Howells <dhowells@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-12-11 09:17:39 -08:00
Sergey Senozhatsky
01dfee9582 workqueue: remove unneeded kallsyms include
The filw was converted from print_symbol() to %pf some time
ago (044c782ce3 "workqueue: fix checkpatch issues").
kallsyms does not seem to be needed anymore.

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-12-11 07:15:43 -08:00
Randy Dunlap
2064a5ab04 sched/core: Fix kernel-doc warnings after code movement
Fix the following kernel-doc warnings after code restructuring:

  ../kernel/sched/core.c:5113: warning: No description found for parameter 't'
  ../kernel/sched/core.c:5113: warning: Excess function parameter 'interval' description in 'sched_rr_get_interval'

	get rid of set_fs()")

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: abca5fc535 ("sched_rr_get_interval(): move compat to native,
Link: http://lkml.kernel.org/r/995c6ded-b32e-bbe4-d9f5-4d42d121aff1@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-11 16:10:42 +01:00
Jiri Slaby
d70ef22892 futex: futex_wake_op, fix sign_extend32 sign bits
sign_extend32 counts the sign bit parameter from 0, not from 1.  So we
have to use "11" for 12th bit, not "12".

This mistake means we have not allowed negative op and cmp args since
commit 30d6e0a419 ("futex: Remove duplicated code and fix undefined
behaviour") till now.

Fixes: 30d6e0a419 ("futex: Remove duplicated code and fix undefined behaviour")
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <dvhart@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-12-10 12:50:57 -08:00
Linus Torvalds
e9ef1fe312 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) CAN fixes from Martin Kelly (cancel URBs properly in all the CAN usb
    drivers).

 2) Revert returning -EEXIST from __dev_alloc_name() as this propagates
    to userspace and broke some apps. From Johannes Berg.

 3) Fix conn memory leaks and crashes in TIPC, from Jon Malloc and Cong
    Wang.

 4) Gianfar MAC can't do EEE so don't advertise it by default, from
    Claudiu Manoil.

 5) Relax strict netlink attribute validation, but emit a warning. From
    David Ahern.

 6) Fix regression in checksum offload of thunderx driver, from Florian
    Westphal.

 7) Fix UAPI bpf issues on s390, from Hendrik Brueckner.

 8) New card support in iwlwifi, from Ihab Zhaika.

 9) BBR congestion control bug fixes from Neal Cardwell.

10) Fix port stats in nfp driver, from Pieter Jansen van Vuuren.

11) Fix leaks in qualcomm rmnet, from Subash Abhinov Kasiviswanathan.

12) Fix DMA API handling in sh_eth driver, from Thomas Petazzoni.

13) Fix spurious netpoll warnings in bnxt_en, from Calvin Owens.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (67 commits)
  net: mvpp2: fix the RSS table entry offset
  tcp: evaluate packet losses upon RTT change
  tcp: fix off-by-one bug in RACK
  tcp: always evaluate losses in RACK upon undo
  tcp: correctly test congestion state in RACK
  bnxt_en: Fix sources of spurious netpoll warnings
  tcp_bbr: reset long-term bandwidth sampling on loss recovery undo
  tcp_bbr: reset full pipe detection on loss recovery undo
  tcp_bbr: record "full bw reached" decision in new full_bw_reached bit
  sfc: pass valid pointers from efx_enqueue_unwind
  gianfar: Disable EEE autoneg by default
  tcp: invalidate rate samples during SACK reneging
  can: peak/pcie_fd: fix potential bug in restarting tx queue
  can: usb_8dev: cancel urb on -EPIPE and -EPROTO
  can: kvaser_usb: cancel urb on -EPIPE and -EPROTO
  can: esd_usb2: cancel urb on -EPIPE and -EPROTO
  can: ems_usb: cancel urb on -EPIPE and -EPROTO
  can: mcba_usb: cancel urb on -EPROTO
  usbnet: fix alignment for frames with no ethernet header
  tcp: use current time in tcp_rcv_space_adjust()
  ...
2017-12-08 13:32:44 -08:00
Cheng Jian
a555e9d86e sched/fair: Remove unused 'curr' parameter from wakeup_gran
The first parameter of wakeup_gran(), 'curr', is unnecessary now.

Signed-off-by: Cheng Jian <cj.chengjian@huawei.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: huawei.libin@huawei.com
Cc: xiexiuqi@huawei.com
Link: http://lkml.kernel.org/r/1512653443-179848-1-git-send-email-cj.chengjian@huawei.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-08 07:51:53 +01:00
Paul E. McKenney
156baec397 rcu: Export init_rcu_head() and destroy_rcu_head() to GPL modules
Use of init_rcu_head() and destroy_rcu_head() from modules results in
the following build-time error with CONFIG_DEBUG_OBJECTS_RCU_HEAD=y:

	ERROR: "init_rcu_head" [drivers/scsi/scsi_mod.ko] undefined!
	ERROR: "destroy_rcu_head" [drivers/scsi/scsi_mod.ko] undefined!

This commit therefore adds EXPORT_SYMBOL_GPL() for each to allow them to
be used by GPL-licensed kernel modules.

Reported-by: Bart Van Assche <Bart.VanAssche@wdc.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-12-07 19:51:49 -05:00
Linus Torvalds
968edbd93c KGDB:
* Fix long standing problem with kdb kallsyms_symbol_next() return value
    * Add new co-maintainer Daniel Thompson
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJaKG1/AAoJEIciOldedpOjtigP/Rp1CK9EGtzZCW7a1wZp7d/n
 OsAUKrj1AEvve+PpZXBw9X3XMYpXbGyzDfU59NLzMZmgZ6idIdwBwlO6AgWSRyXY
 EjvYOvkIytk2ONFVQeDPfbAi5pPaSgTmt813pApka4mbUlWYgC4TioNove4Q08R+
 CZrXiD2WeKlBxB2TgfYu+0Sy3TtYv7aaJhV45ziPjiwyFpcl9Ktp5zEVOcK6Xw10
 8T5ZLA7k/MKah+CoqBdzRZ0IprBVAB4MMTBV3q7HXNXOMX6JdXgg1UihqKJcYF5u
 6d+PS6A8sFGicUguPXMZh90vM2f0hg+ZagavskSLCp8usL91+4UmAxHaRdKUTqWC
 k1jmxODsJPiBFi05mSem94WtegjBkrUMohGcKyfjEdixjZfa9G6Zhux/951HFkrl
 UdUSlTnfO39Cj3V5AkSR95wBVuPgjMKSBVDxKuUrWib2p3Wx0P/eeDtcgy+yPHkX
 Gxxa5nhmBUJJZCWl08kKQ1oacVX5/sg9ZcmpAXzcR3lLYL/GlgiB9tS8piRGLUN6
 GVneU5uqVnj1Jm67J7SVZtPsvbhV2jEP9aeNx8MZzaTJ412XzYeMB9P88JFQpZRj
 UXxhF/Q5HsjxKX0XKUD9O3W4KXD1YYWHng3ljarzR25Sd3zA7Y5HJ3NnCZRRa3Mm
 hVgJQIk1xB40aNnRVXJT
 =2jeq
 -----END PGP SIGNATURE-----

Merge tag 'for_linus-4.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb

Pull kgdb fixes from Jason Wessel:

 - Fix long standing problem with kdb kallsyms_symbol_next() return
   value

 - Add new co-maintainer Daniel Thompson

* tag 'for_linus-4.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb:
  kgdb/kdb/debug_core: Add co-maintainer Daniel Thompson
  kdb: Fix handling of kallsyms_symbol_next() return value
2017-12-06 18:33:17 -08:00
Linus Torvalds
4b43a3bc20 Merge branch 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull CPU hotplug fix from Ingo Molnar:
 "A single fix moving the smp-call queue flush step to the intended
  point in the state machine"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  smp/hotplug: Move step CPUHP_AP_SMPCFD_DYING to the correct place
2017-12-06 17:45:36 -08:00
Linus Torvalds
e017b4db26 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "This includes a fix for the add_wait_queue() queue ordering brown
  paperbag bug, plus PELT accounting fixes for cgroups scheduling
  artifacts"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/fair: Update and fix the runnable propagation rule
  sched/wait: Fix add_wait_queue() behavioral change
2017-12-06 17:43:26 -08:00
Linus Torvalds
1c7647253c Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "This includes perf namespace support kernel side fixes, plus an
  accumulated set of perf tooling fixes - including UAPI header
  synchronization that should make the perf build less noisy"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits)
  tooling/headers: Synchronize updated s390 and x86 UAPI headers
  tools headers: Syncronize mman.h ABI header
  tools headers: Synchronize prctl.h ABI header
  tools headers: Synchronize KVM arch ABI headers
  tools headers: Synchronize drm/i915_drm.h
  tools headers uapi: Synchronize drm/drm.h
  tools headers: Synchronize perf_event.h header
  tools headers: Synchronize kernel ABI headers wrt SPDX tags
  tools/headers: Synchronize kernel x86 UAPI headers
  perf intel-pt: Bring instruction decoder files into line with the kernel
  perf test: Fix test 21 for s390x
  perf bench numa: Fixup discontiguous/sparse numa nodes
  perf top: Use signal interface for SIGWINCH handler
  perf top: Fix window dimensions change handling
  perf: Fix header.size for namespace events
  perf top: Ignore kptr_restrict when not sampling the kernel
  perf record: Ignore kptr_restrict when not sampling the kernel
  perf report: Ignore kptr_restrict when not sampling the kernel
  perf evlist: Add helper to check if attr.exclude_kernel is set in all evsels
  perf test shell: Fix test case probe libc's inet_pton on s390x
  ...
2017-12-06 17:41:24 -08:00
Linus Torvalds
189dbab0dd Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull lockdep fix from Ingo Molnar:
 "Fix a possible NULL dereference for the (rare) case when a task
  doesn't have ->xhlocks space allocated due to kmalloc() OOM-ing"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/lockdep: Fix possible NULL deref
2017-12-06 17:39:44 -08:00
Linus Torvalds
61d6be3a7a Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Ingo Molnar:
 "Two fixes: use bool type consistently, plus a irq_matrix_available()
  bugfix"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqdesc: Use bool return type instead of int
  genirq/matrix: Fix the precedence fix for real
2017-12-06 15:47:51 -08:00
Daniel Thompson
c07d353380 kdb: Fix handling of kallsyms_symbol_next() return value
kallsyms_symbol_next() returns a boolean (true on success). Currently
kdb_read() tests the return value with an inequality that
unconditionally evaluates to true.

This is fixed in the obvious way and, since the conditional branch is
supposed to be unreachable, we also add a WARN_ON().

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2017-12-06 16:12:43 -06:00
Ingo Molnar
d6eabce257 Merge branch 'linus' into perf/urgent, to synchronize UAPI headers
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-06 22:39:39 +01:00
Vincent Guittot
a4c3c04974 sched/fair: Update and fix the runnable propagation rule
Unlike running, the runnable part can't be directly propagated through
the hierarchy when we migrate a task. The main reason is that runnable
time can be shared with other sched_entities that stay on the rq and
this runnable time will also remain on prev cfs_rq and must not be
removed.

Instead, we can estimate what should be the new runnable of the prev
cfs_rq and check that this estimation stay in a possible range. The
prop_runnable_sum is a good estimation when adding runnable_sum but
fails most often when we remove it. Instead, we could use the formula
below instead:

  gcfs_rq's runnable_sum = gcfs_rq->avg.load_sum / gcfs_rq->load.weight

which assumes that tasks are equally runnable which is not true but
easy to compute.

Beside these estimates, we have several simple rules that help us to filter
out wrong ones:

 - ge->avg.runnable_sum <= than LOAD_AVG_MAX
 - ge->avg.runnable_sum >= ge->avg.running_sum (ge->avg.util_sum << LOAD_AVG_MAX)
 - ge->avg.runnable_sum can't increase when we detach a task

The effect of these fixes is better cgroups balancing.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Chris Mason <clm@fb.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yuyang Du <yuyang.du@intel.com>
Link: http://lkml.kernel.org/r/1510842112-21028-1-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-06 19:30:50 +01:00
Omar Sandoval
c6b9d9a330 sched/wait: Fix add_wait_queue() behavioral change
The following cleanup commit:

  50816c4899 ("sched/wait: Standardize internal naming of wait-queue entries")

... unintentionally changed the behavior of add_wait_queue() from
inserting the wait entry at the head of the wait queue to the tail
of the wait queue.

Beyond a negative performance impact this change in behavior
theoretically also breaks wait queues which mix exclusive and
non-exclusive waiters, as non-exclusive waiters will not be
woken up if they are queued behind enough exclusive waiters.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-team@fb.com
Fixes: ("sched/wait: Standardize internal naming of wait-queue entries")
Link: http://lkml.kernel.org/r/a16c8ccffd39bd08fdaa45a5192294c784b803a7.1512544324.git.osandov@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-06 19:30:34 +01:00
Peter Zijlstra
5e351ad106 locking/lockdep: Fix possible NULL deref
We can't invalidate xhlocks when we've not yet allocated any.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Fixes: f52be57080 ("locking/lockdep: Untangle xhlock history save/restore from task independence")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-06 19:29:56 +01:00
Brendan Jackman
5b1ead6800 cpu/hotplug: Fix state name in takedown_cpu() comment
CPUHP_AP_SCHED_MIGRATE_DYING doesn't exist, it looks like this was
supposed to refer to CPUHP_AP_SCHED_STARTING's teardown callback,
i.e. sched_cpu_dying().

Signed-off-by: Brendan Jackman <brendan.jackman@arm.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Perret <quentin.perret@arm.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20171206105911.28093-1-brendan.jackman@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-06 19:28:45 +01:00
Linus Torvalds
b7ad7ef742 remove task and stack pointer printout from oops dump
Geert Uytterhoeven reported a NFS oops, and pointed out that some of the
numbers were hashed and useless.

We could just turn them from '%p' into '%px', but those numbers are
really just legacy, and useless even when not hashed.

So just remove them entirely.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-12-05 08:23:20 -08:00
Hendrik Brueckner
c895f6f703 bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type
Commit 0515e5999a ("bpf: introduce BPF_PROG_TYPE_PERF_EVENT
program type") introduced the bpf_perf_event_data structure which
exports the pt_regs structure.  This is OK for multiple architectures
but fail for s390 and arm64 which do not export pt_regs.  Programs
using them, for example, the bpf selftest fail to compile on these
architectures.

For s390, exporting the pt_regs is not an option because s390 wants
to allow changes to it.  For arm64, there is a user_pt_regs structure
that covers parts of the pt_regs structure for use by user space.

To solve the broken uapi for s390 and arm64, introduce an abstract
type for pt_regs and add an asm/bpf_perf_event.h file that concretes
the type.  An asm-generic header file covers the architectures that
export pt_regs today.

The arch-specific enablement for s390 and arm64 follows in separate
commits.

Reported-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Fixes: 0515e5999a ("bpf: introduce BPF_PROG_TYPE_PERF_EVENT program type")
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-and-tested-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-05 15:02:40 +01:00
Tejun Heo
bdfbbda90a Revert "cgroup/cpuset: remove circular dependency deadlock"
This reverts commit aa24163b2e.

This and the following commit led to another circular locking scenario
and the scenario which is fixed by this commit no longer exists after
e8b3f8db7a ("workqueue/hotplug: simplify workqueue_offline_cpu()")
which removes work item flushing from hotplug path.

Revert it for now.

Signed-off-by: Tejun Heo <tj@kernel.org>
2017-12-04 14:55:59 -08:00
Lai Jiangshan
62408c1ef0 workqueue/hotplug: remove the workaround in rebind_workers()
Since the cpu/hotplug refactoring, DOWN_FAILED is never called without
preceding DOWN_PREPARE making the workaround unnecessary.  Remove it.

Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-12-04 14:46:09 -08:00
Lai Jiangshan
e8b3f8db7a workqueue/hotplug: simplify workqueue_offline_cpu()
Since the recent cpu/hotplug refactoring, workqueue_offline_cpu() is
guaranteed to run on the local cpu which is going offline.

This also fixes the following deadlock by removing work item
scheduling and flushing from CPU hotplug path.

 http://lkml.kernel.org/r/1504764252-29091-1-git-send-email-prsood@codeaurora.org

tj: Description update.

Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-12-04 14:44:11 -08:00
Tejun Heo
11db855c3d Revert "cpuset: Make cpuset hotplug synchronous"
This reverts commit 1599a185f0.

This and the previous commit led to another circular locking scenario
and the scenario which is fixed by this commit no longer exists after
e8b3f8db7a ("workqueue/hotplug: simplify workqueue_offline_cpu()")
which removes work item flushing from hotplug path.

Revert it for now.

Signed-off-by: Tejun Heo <tj@kernel.org>
2017-12-04 14:41:11 -08:00
Thomas Gleixner
bb5c434282 genirq/matrix: Fix the precedence fix for real
The previous commit which made the operator precedence in
irq_matrix_available() explicit made the implicit brokenness explicitely
wrong. It was wrong in the original commit already. The overworked
maintainer did not notice it either when merging the patch.

Replace the confusing '?' construct by a simple and obvious if ().

Fixes: 75f1133873 ("genirq/matrix: Make - vs ?: Precedence explicit")
Reported-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Kees Cook <keescook@chromium.org>
2017-12-04 20:50:35 +01:00
Linus Torvalds
236fa078c6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Various TCP control block fixes, including one that crashes with
    SELinux, from David Ahern and Eric Dumazet.

 2) Fix ACK generation in rxrpc, from David Howells.

 3) ipvlan doesn't set the mark properly in the ipv4 route lookup key,
    from Gao Feng.

 4) SIT configuration doesn't take on the frag_off ipv4 field
    configuration properly, fix from Hangbin Liu.

 5) TSO can fail after device down/up on stmmac, fix from Lars Persson.

 6) Various bpftool fixes (mostly in JSON handling) from Quentin Monnet.

 7) Various SKB leak fixes in vhost/tun/tap (mostly observed as
    performance problems). From Wei Xu.

 8) mvpps's TX descriptors were not zero initialized, from Yan Markman.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (57 commits)
  tcp: use IPCB instead of TCP_SKB_CB in inet_exact_dif_match()
  tcp: add tcp_v4_fill_cb()/tcp_v4_restore_cb()
  rxrpc: Fix the MAINTAINERS record
  rxrpc: Use correct netns source in rxrpc_release_sock()
  liquidio: fix incorrect indentation of assignment statement
  stmmac: reset last TSO segment size after device open
  ipvlan: Add the skb->mark as flow4's member to lookup route
  s390/qeth: build max size GSO skbs on L2 devices
  s390/qeth: fix GSO throughput regression
  s390/qeth: fix thinko in IPv4 multicast address tracking
  tap: free skb if flags error
  tun: free skb in early errors
  vhost: fix skb leak in handle_rx()
  bnxt_en: Fix a variable scoping in bnxt_hwrm_do_send_msg()
  bnxt_en: fix dst/src fid for vxlan encap/decap actions
  bnxt_en: wildcard smac while creating tunnel decap filter
  bnxt_en: Need to unconditionally shut down RoCE in bnxt_shutdown
  phylink: ensure we take the link down when phylink_stop() is called
  sfp: warn about modules requiring address change sequence
  sfp: improve RX_LOS handling
  ...
2017-12-04 11:14:46 -08:00
Paul E. McKenney
243d1a7977 tracepoint: Remove smp_read_barrier_depends() from comment
The comment in tracepoint_add_func() mentions smp_read_barrier_depends(),
whose use should be quite restricted.  This commit updates the comment
to instead mention the smp_store_release() and rcu_dereference_sched()
that the current code actually uses.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
2017-12-04 10:52:56 -08:00
Paul E. McKenney
548095dea6 locking: Remove smp_read_barrier_depends() from queued_spin_lock_slowpath()
Queued spinlocks are not used by DEC Alpha, and furthermore operations
such as READ_ONCE() and release/relaxed RMW atomics are being changed
to imply smp_read_barrier_depends().  This commit therefore removes the
now-redundant smp_read_barrier_depends() from queued_spin_lock_slowpath(),
and adjusts the comments accordingly.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
2017-12-04 10:52:55 -08:00
Paul E. McKenney
5c6338b487 uprobes: Remove now-redundant smp_read_barrier_depends()
Now that READ_ONCE() implies smp_read_barrier_depends(), the
get_xol_area() and get_trampoline_vaddr() no longer need their
smp_read_barrier_depends() calls, which this commit removes.
While we are here, convert the corresponding smp_wmb() to an
smp_store_release().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
2017-12-04 10:52:55 -08:00
Paul E. McKenney
edf22f4ca2 softirq: Eliminate cond_resched_rcu_qs() in favor of cond_resched()
Now that cond_resched() also provides RCU quiescent states when
needed, it can be used in place of cond_resched_rcu_qs().  This
commit therefore makes this change.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: NeilBrown <neilb@suse.com>
Cc: Ingo Molnar <mingo@kernel.org>
2017-12-04 10:28:58 -08:00
Paul E. McKenney
e31d28b6ab trace: Eliminate cond_resched_rcu_qs() in favor of cond_resched()
Now that cond_resched() also provides RCU quiescent states when
needed, it can be used in place of cond_resched_rcu_qs().  This
commit therefore makes this change.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
2017-12-04 10:28:58 -08:00
Paul E. McKenney
a7e6425ea5 workqueue: Eliminate cond_resched_rcu_qs() in favor of cond_resched()
Now that cond_resched() also provides RCU quiescent states when
needed, it can be used in place of cond_resched_rcu_qs().  This
commit therefore makes this change.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>
2017-12-04 10:28:10 -08:00
Mark Brown
4ab53fe612 PM: Provide a config snippet for disabling PM
A frequent source of build problems is poor handling of optional PM
support, almost all development is done with the PM options enabled
but they can be turned off.  Currently few if any of the build test
services do this as standard as there is no standard config for it and
the use of selects and def_bool means that simply setting CONFIG_PM=n
doesn't do what is expected.  To make this easier provide a fragement
that can be used with KCONFIG_ALLCONFIG to force PM off.

CONFIG_XEN is disabled as Xen uses hibernation callbacks which end up
turning on power management on architectures with Xen.  Some cpuidle
implementations on ARM select PM so CONFIG_CPU_IDLE is disabled, and
some ARM architectures unconditionally enable PM so they are also
disabled.

Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-12-04 15:14:48 +01:00
Felipe Balbi
a773d41927 tracing: Pass export pointer as argument to ->write()
By passing an export descriptor to the write function, users don't need to
keep a global static pointer and can rely on container_of() to fetch their
own structure.

Link: http://lkml.kernel.org/r/20170602102025.5140-1-felipe.balbi@linux.intel.com

Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-04 07:14:30 -05:00
Matthias Kaehlcke
c4bfd39d7f ring-buffer: Remove unused function __rb_data_page_index()
This fixes the following warning when building with clang:

kernel/trace/ring_buffer.c:1842:1: error: unused function
    '__rb_data_page_index' [-Werror,-Wunused-function]

Link: http://lkml.kernel.org/r/20170518001415.5223-1-mka@chromium.org

Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-04 07:04:01 -05:00
Arnd Bergmann
2dde6b0034 tracing: make PREEMPTIRQ_EVENTS depend on TRACING
When CONFIG_TRACING is disabled, the new preemptirq events tracer
produces a build failure:

In file included from kernel/trace/trace_irqsoff.c:17:0:
kernel/trace/trace.h: In function 'trace_test_and_set_recursion':
kernel/trace/trace.h:542:28: error: 'struct task_struct' has no member named 'trace_recursion'

Adding an explicit dependency avoids the broken configuration.

Link: http://lkml.kernel.org/r/20171103104031.270375-1-arnd@arndb.de

Fixes: d59158162e ("tracing: Add support for preempt and irq enable/disable events")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-04 06:52:09 -05:00
Changbin Du
90e406f96f tracing: Allocate mask_str buffer dynamically
The default NR_CPUS can be very large, but actual possible nr_cpu_ids
usually is very small. For my x86 distribution, the NR_CPUS is 8192 and
nr_cpu_ids is 4. About 2 pages are wasted.

Most machines don't have so many CPUs, so define a array with NR_CPUS
just wastes memory. So let's allocate the buffer dynamically when need.

With this change, the mutext tracing_cpumask_update_lock also can be
removed now, which was used to protect mask_str.

Link: http://lkml.kernel.org/r/1512013183-19107-1-git-send-email-changbin.du@intel.com

Fixes: 36dfe9252b ("ftrace: make use of tracing_cpumask")
Cc: stable@vger.kernel.org
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-04 06:52:08 -05:00
Chunyu Hu
5a93bae2c3 tracing: Fix code comments in trace.c
Naming in code comments for tracing_snapshot, tracing_snapshot_alloc
and trace_pid_filter_add_remove_task don't match the real function
names.  And latency_trace has been removed from tracing directory.
Fix them.

Link: http://lkml.kernel.org/r/1508394753-20887-1-git-send-email-chuhu@redhat.com

Fixes: cab5037 ("tracing/ftrace: Enable snapshot function trigger")
Fixes: 886b5b7 ("tracing: remove /debug/tracing/latency_trace")
Signed-off-by: Chunyu Hu <chuhu@redhat.com>
[ Replaced /sys/kernel/debug/tracing with /sys/kerne/tracing ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-04 06:52:07 -05:00
David S. Miller
c2eb6d07a6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2017-12-02

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Fix a compilation warning in xdp redirect tracepoint due to
   missing bpf.h include that pulls in struct bpf_map, from Xie.

2) Limit the maximum number of attachable BPF progs for a given
   perf event as long as uabi is not frozen yet. The hard upper
   limit is now 64 and therefore the same as with BPF multi-prog
   for cgroups. Also add related error checking for the sample
   BPF loader when enabling and attaching to the perf event, from
   Yonghong.

3) Specifically set the RLIMIT_MEMLOCK for the test_verifier_log
   case, so that the test case can always pass and not fail in
   some environments due to too low default limit, also from
   Yonghong.

4) Fix up a missing license header comment for kernel/bpf/offload.c,
   from Jakub.

5) Several fixes for bpftool, among others a crash on incorrect
   arguments when json output is used, error message handling
   fixes on unknown options and proper destruction of json writer
   for some exit cases, all from Quentin.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-03 13:08:30 -05:00
Linus Torvalds
75f64f68af Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
 "A selection of fixes/changes that should make it into this series.
  This contains:

   - NVMe, two merges, containing:
        - pci-e, rdma, and fc fixes
        - Device quirks

   - Fix for a badblocks leak in null_blk

   - bcache fix from Rui Hua for a race condition regression where
     -EINTR was returned to upper layers that didn't expect it.

   - Regression fix for blktrace for a bug introduced in this series.

   - blktrace cleanup for cgroup id.

   - bdi registration error handling.

   - Small series with cleanups for blk-wbt.

   - Various little fixes for typos and the like.

  Nothing earth shattering, most important are the NVMe and bcache fixes"

* 'for-linus' of git://git.kernel.dk/linux-block: (34 commits)
  nvme-pci: fix NULL pointer dereference in nvme_free_host_mem()
  nvme-rdma: fix memory leak during queue allocation
  blktrace: fix trace mutex deadlock
  nvme-rdma: Use mr pool
  nvme-rdma: Check remotely invalidated rkey matches our expected rkey
  nvme-rdma: wait for local invalidation before completing a request
  nvme-rdma: don't complete requests before a send work request has completed
  nvme-rdma: don't suppress send completions
  bcache: check return value of register_shrinker
  bcache: recover data from backing when data is clean
  bcache: Fix building error on MIPS
  bcache: add a comment in journal bucket reading
  nvme-fc: don't use bit masks for set/test_bit() numbers
  blk-wbt: fix comments typo
  blk-wbt: move wbt_clear_stat to common place in wbt_done
  blk-sysfs: remove NULL pointer checking in queue_wb_lat_store
  blk-wbt: remove duplicated setting in wbt_init
  nvme-pci: add quirk for delay before CHK RDY for WDC SN200
  block: remove useless assignment in bio_split
  null_blk: fix dev->badblocks leak
  ...
2017-12-01 08:05:45 -05:00
Yonghong Song
c8c088ba0e bpf: set maximum number of attached progs to 64 for a single perf tp
cgropu+bpf prog array has a maximum number of 64 programs.
Let us apply the same limit here.

Fixes: e87c6bc385 ("bpf: permit multiple bpf attachments for a single perf event")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-01 02:56:10 +01:00
Linus Torvalds
668533dc07 kallsyms: take advantage of the new '%px' format
The conditional kallsym hex printing used a special fixed-width '%lx'
output (KALLSYM_FMT) in preparation for the hashing of %p, but that
series ended up adding a %px specifier to help with the conversions.

Use it, and avoid the "print pointer as an unsigned long" code.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-29 10:30:13 -08:00
Ingo Molnar
6e948c67c4 Merge branch 'perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent
Pull perf tooling fixes from Arnaldo Carvalho de Melo:

"- Fix window dimensions change handling in 'perf top' (Jiri Olsa)

- Fix 'perf record -c/-F' options for CPU event aliases (Andi Kleen)

- Generate PERF_RECORD_{MMAP,COMM,EXEC} with 'perf record --delay'
  fixing symbol resolution for processes created, maps put in place
  while --delay happens (Arnaldo Carvalho de Melo)

- Fix up leftover perf_evsel_stat usage via evsel->priv, plugging
  a SEGV when using event groups as in:

     $ perf stat -e '{cpu-clock,instructions}' workload

- Fix 'perf script --per-event-dump' for auxtrace synth evsels (Arnaldo Carvalho de Melo)

- Ignore kptr_restrict when not sampling the kernel (Arnaldo Carvalho de Melo)

- Synchronize kernel ABI headers wrt SPDX tags and ABI changes,
  taking minimal action to handle new syscall args and silencing
  perf build warnings (Arnaldo Carvalho de Melo, Ingo Molnar)

- Fix header.size for namespace events (Jiri Olsa)

- Fix a bug during strstart() conversion in 'perf help' (Namhyung Kim)

- Do not truncate instruction names at 6 chars in 'perf annotate', there
  are really long instruction names in PPC (Ravi Bangoria)

- Fixup discontiguous/sparse numa nodes in 'perf bench numa' (Satheesh Rajendran)

- Fix an exit code of trace__symbols_init in 'perf trace' (Andrei Vagin)

- Fix 'perf test' entries on s/390 (Thomas Richter)

- Bring instruction decoder files used by Intel PT into line with the kernel,
  silencing build warning (Adrian Hunter)"

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-29 07:15:09 +01:00
Ingo Molnar
4fc31ba13d Merge branch 'linus' into perf/urgent, to pick up dependent commits
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-29 07:11:24 +01:00
Paul E. McKenney
2fe2582649 sched: Stop switched_to_rt() from sending IPIs to offline CPUs
The rcutorture test suite occasionally provokes a splat due to invoking
rt_mutex_lock() which needs to boost the priority of a task currently
sitting on a runqueue that belongs to an offline CPU:

WARNING: CPU: 0 PID: 12 at /home/paulmck/public_git/linux-rcu/arch/x86/kernel/smp.c:128 native_smp_send_reschedule+0x37/0x40
Modules linked in:
CPU: 0 PID: 12 Comm: rcub/7 Not tainted 4.14.0-rc4+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
task: ffff9ed3de5f8cc0 task.stack: ffffbbf80012c000
RIP: 0010:native_smp_send_reschedule+0x37/0x40
RSP: 0018:ffffbbf80012fd10 EFLAGS: 00010082
RAX: 000000000000002f RBX: ffff9ed3dd9cb300 RCX: 0000000000000004
RDX: 0000000080000004 RSI: 0000000000000086 RDI: 00000000ffffffff
RBP: ffffbbf80012fd10 R08: 000000000009da7a R09: 0000000000007b9d
R10: 0000000000000001 R11: ffffffffbb57c2cd R12: 000000000000000d
R13: ffff9ed3de5f8cc0 R14: 0000000000000061 R15: ffff9ed3ded59200
FS:  0000000000000000(0000) GS:ffff9ed3dea00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000080686f0 CR3: 000000001b9e0000 CR4: 00000000000006f0
Call Trace:
 resched_curr+0x61/0xd0
 switched_to_rt+0x8f/0xa0
 rt_mutex_setprio+0x25c/0x410
 task_blocks_on_rt_mutex+0x1b3/0x1f0
 rt_mutex_slowlock+0xa9/0x1e0
 rt_mutex_lock+0x29/0x30
 rcu_boost_kthread+0x127/0x3c0
 kthread+0x104/0x140
 ? rcu_report_unblock_qs_rnp+0x90/0x90
 ? kthread_create_on_node+0x40/0x40
 ret_from_fork+0x22/0x30
Code: f0 00 0f 92 c0 84 c0 74 14 48 8b 05 34 74 c5 00 be fd 00 00 00 ff 90 a0 00 00 00 5d c3 89 fe 48 c7 c7 a0 c6 fc b9 e8 d5 b5 06 00 <0f> ff 5d c3 0f 1f 44 00 00 8b 05 a2 d1 13 02 85 c0 75 38 55 48

But the target task's priority has already been adjusted, so the only
purpose of switched_to_rt() invoking resched_curr() is to wake up the
CPU running some task that needs to be preempted by the boosted task.
But the CPU is offline, which presumably means that the task must be
migrated to some other CPU, and that this other CPU will undertake any
needed preemption at the time of migration.  Because the runqueue lock
is held when resched_curr() is invoked, we know that the boosted task
cannot go anywhere, so it is not necessary to invoke resched_curr()
in this particular case.

This commit therefore makes switched_to_rt() refrain from invoking
resched_curr() when the target CPU is offline.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
2017-11-28 16:00:27 -08:00
Paul E. McKenney
a0982dfa03 sched: Stop resched_cpu() from sending IPIs to offline CPUs
The rcutorture test suite occasionally provokes a splat due to invoking
resched_cpu() on an offline CPU:

WARNING: CPU: 2 PID: 8 at /home/paulmck/public_git/linux-rcu/arch/x86/kernel/smp.c:128 native_smp_send_reschedule+0x37/0x40
Modules linked in:
CPU: 2 PID: 8 Comm: rcu_preempt Not tainted 4.14.0-rc4+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
task: ffff902ede9daf00 task.stack: ffff96c50010c000
RIP: 0010:native_smp_send_reschedule+0x37/0x40
RSP: 0018:ffff96c50010fdb8 EFLAGS: 00010096
RAX: 000000000000002e RBX: ffff902edaab4680 RCX: 0000000000000003
RDX: 0000000080000003 RSI: 0000000000000000 RDI: 00000000ffffffff
RBP: ffff96c50010fdb8 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 00000000299f36ae R12: 0000000000000001
R13: ffffffff9de64240 R14: 0000000000000001 R15: ffffffff9de64240
FS:  0000000000000000(0000) GS:ffff902edfc80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f7d4c642 CR3: 000000001e0e2000 CR4: 00000000000006e0
Call Trace:
 resched_curr+0x8f/0x1c0
 resched_cpu+0x2c/0x40
 rcu_implicit_dynticks_qs+0x152/0x220
 force_qs_rnp+0x147/0x1d0
 ? sync_rcu_exp_select_cpus+0x450/0x450
 rcu_gp_kthread+0x5a9/0x950
 kthread+0x142/0x180
 ? force_qs_rnp+0x1d0/0x1d0
 ? kthread_create_on_node+0x40/0x40
 ret_from_fork+0x27/0x40
Code: 14 01 0f 92 c0 84 c0 74 14 48 8b 05 14 4f f4 00 be fd 00 00 00 ff 90 a0 00 00 00 5d c3 89 fe 48 c7 c7 38 89 ca 9d e8 e5 56 08 00 <0f> ff 5d c3 0f 1f 44 00 00 8b 05 52 9e 37 02 85 c0 75 38 55 48
---[ end trace 26df9e5df4bba4ac ]---

This splat cannot be generated by expedited grace periods because they
always invoke resched_cpu() on the current CPU, which is good because
expedited grace periods require that resched_cpu() unconditionally
succeed.  However, other parts of RCU can tolerate resched_cpu() acting
as a no-op, at least as long as it doesn't happen too often.

This commit therefore makes resched_cpu() invoke resched_curr() only if
the CPU is either online or is the current CPU.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
2017-11-28 16:00:26 -08:00
Paul E. McKenney
dac9590600 torture: Suppress CPU stall warnings during shutdown ftrace dump
The torture_shutdown() function directly invokes ftrace_dump(), which
can result in RCU CPU stall warnings when the ftrace buffer is large,
which it usually is.  This commit therefore invoks rcu_ftrace_dump()
in place of ftrace_dump(), suppressing RCU CPU stall warnings during
this time.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-11-28 15:54:26 -08:00
Paul E. McKenney
d633198088 srcu: Prohibit call_srcu() use under raw spinlocks
Invoking queue_delayed_work() while holding a raw spinlock is forbidden
in -rt kernels, which is exactly what __call_srcu() does, indirectly via
srcu_funnel_gp_start().  This commit therefore downgrades Tree SRCU's
locking from raw to non-raw spinlocks, which works because call_srcu()
is not ever called while holding a raw spinlock.

Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-11-28 15:52:33 -08:00
Paul E. McKenney
e68bbb266d rcu: Simplify rcu_eqs_{enter,exit}() non-idle task debug code
The code that checks for non-idle non-nohz_idle-usermode tasks invoking
rcu_eqs_enter() and rcu_eqs_exit() prints a considerable quantity of
helpful information.  However, these checks fire rarely, so the extra
complexity is no longer worth it.  This commit therefore replaces this
debug code with simple WARN_ON_ONCE() statements.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-11-28 15:51:21 -08:00
Paul E. McKenney
9dd238e286 rcu: Fold rcu_eqs_exit_common() into rcu_eqs_exit()
There is now only one call to rcu_eqs_exit_common() and there is no other
reason to keep it separate.  This commit therefore inlines it into its
sole call site, saving a few lines of code in the process.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-11-28 15:51:21 -08:00
Paul E. McKenney
215bba9f59 rcu: Fold rcu_eqs_enter_common() into rcu_eqs_enter()
There is now only one call to rcu_eqs_enter_common() and there is no other
reason to keep it separate.  This commit therefore inlines it into its
sole call site, saving a few lines of code in the process.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-11-28 15:51:20 -08:00
Paul E. McKenney
2342172fd6 rcu: Avoid ->dynticks_nesting store tearing
Although ->dynticks_nesting is updated only by process level, it is
accessed from hardirq to check for interrupt-from-idle quiescent states.
Store tearing is thus possible, so this commit applies WRITE_ONCE()
to ->dynticks_nesting stores.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-11-28 15:51:20 -08:00
Paul E. McKenney
914955e18c rcu: Stop duplicating lockdep checks in RCU's idle-entry code
The three RCU_LOCKDEP_WARN() calls in rcu_eqs_enter_common() are
redundant with other lockdep checks, so this commit removes them.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-11-28 15:51:19 -08:00
Paul E. McKenney
dec98900ea rcu: Add ->dynticks field to rcu_dyntick trace event
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-11-28 15:51:19 -08:00
Paul E. McKenney
84585aa8b6 rcu: Shrink ->dynticks_{nmi_,}nesting from long long to long
Because the ->dynticks_nesting field now only contains the process-based
nesting level instead of a value encoding both the process nesting level
and the irq "nesting" level, we no longer need a long long, even on
32-bit systems.  This commit therefore changes both the ->dynticks_nesting
and ->dynticks_nmi_nesting fields to long.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-11-28 15:51:18 -08:00
Paul E. McKenney
bd2b879a1c rcu: Add tracing to irq/NMI dyntick-idle transitions
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-11-28 15:51:18 -08:00
Jiri Olsa
34900ec5c9 perf: Fix header.size for namespace events
Reset header size for namespace events, otherwise it only gets bigger in
ctx iterations.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Fixes: e422267322 ("perf: Add PERF_RECORD_NAMESPACES to include namespaces related info")
Link: http://lkml.kernel.org/n/tip-nlo4gonz9d4guyb8153ukzt0@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-11-28 14:27:05 -03:00
Al Viro
ecf927000c ring_buffer_poll_wait() return value used as return value of ->poll()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-28 11:07:12 -05:00
Lucas Stach
52cf373c37 cgroup: properly init u64_stats
Lockdep complains that the stats update is trying to register a non-static
key. This is because u64_stats are using a seqlock on 32bit arches, which
needs to be initialized before usage.

Fixes: 041cd640b2 (cgroup: Implement cgroup2 basic CPU usage accounting)
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-11-28 07:16:08 -08:00
Lai Jiangshan
46febd37f9 smp/hotplug: Move step CPUHP_AP_SMPCFD_DYING to the correct place
Commit 31487f8328 ("smp/cfd: Convert core to hotplug state machine")
accidently put this step on the wrong place. The step should be at the
cpuhp_ap_states[] rather than the cpuhp_bp_states[].

grep smpcfd /sys/devices/system/cpu/hotplug/states
 40: smpcfd:prepare
129: smpcfd:dying

"smpcfd:dying" was missing before.
So was the invocation of the function smpcfd_dying_cpu().

Fixes: 31487f8328 ("smp/cfd: Convert core to hotplug state machine")
Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: stable@vger.kernel.org
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lkml.kernel.org/r/20171128131954.81229-1-jiangshanlai@gmail.com
2017-11-28 14:40:23 +01:00
Jakub Kicinski
a39e17b2d8 bpf: offload: add a license header
I forgot to add a license on kernel/bpf/offload.c.  Luckily I'm
still the only author so make it explicitly GPLv2.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-27 22:24:51 +01:00
Al Viro
9dd957485d ipc, kernel, mm: annotate ->poll() instances
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-27 16:20:05 -05:00
Wang Long
ddf7005f32 debug cgroup: use task_css_set instead of rcu_dereference
This macro `task_css_set` verifies that the caller is
inside proper critical section if the kernel set CONFIG_PROVE_RCU=y.

Signed-off-by: Wang Long <wanglong19@meituan.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-11-27 11:37:33 -08:00
Jens Axboe
2967acbb25 blktrace: fix trace mutex deadlock
A previous commit changed the locking around registration/cleanup,
but direct callers of blk_trace_remove() were missed. This means
that if we hit the error path in setup, we will deadlock on
attempting to re-acquire the queue trace mutex.

Fixes: 1f2cac107c ("blktrace: fix unlocked access to init/start-stop/teardown")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-27 12:03:58 -07:00
Tal Shorer
c98a980509 workqueue: respect isolated cpus when queueing an unbound work
Initialize wq_unbound_cpumask to exclude cpus that were isolated by
the cmdline's isolcpus parameter.

Signed-off-by: Tal Shorer <tal.shorer@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-11-27 08:57:00 -08:00
Prateek Sood
1599a185f0 cpuset: Make cpuset hotplug synchronous
Convert cpuset_hotplug_workfn() into synchronous call for cpu hotplug
path. For memory hotplug path it still gets queued as a work item.

Since cpuset_hotplug_workfn() can be made synchronous for cpu hotplug
path, it is not required to wait for cpuset hotplug while thawing
processes.

Signed-off-by: Prateek Sood <prsood@codeaurora.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-11-27 08:48:10 -08:00
Prateek Sood
aa24163b2e cgroup/cpuset: remove circular dependency deadlock
Remove circular dependency deadlock in a scenario where hotplug of CPU is
being done while there is updation in cgroup and cpuset triggered from
userspace.

Process A => kthreadd => Process B => Process C => Process A

Process A
cpu_subsys_offline();
  cpu_down();
    _cpu_down();
      percpu_down_write(&cpu_hotplug_lock); //held
      cpuhp_invoke_callback();
	     workqueue_offline_cpu();
            queue_work_on(); // unbind_work on system_highpri_wq
               __queue_work();
                 insert_work();
                    wake_up_worker();
            flush_work();
               wait_for_completion();

worker_thread();
   manage_workers();
      create_worker();
	     kthread_create_on_node();
		    wake_up_process(kthreadd_task);

kthreadd
kthreadd();
  kernel_thread();
    do_fork();
      copy_process();
        percpu_down_read(&cgroup_threadgroup_rwsem);
          __rwsem_down_read_failed_common(); //waiting

Process B
kernfs_fop_write();
  cgroup_file_write();
    cgroup_procs_write();
      percpu_down_write(&cgroup_threadgroup_rwsem); //held
      cgroup_attach_task();
        cgroup_migrate();
          cgroup_migrate_execute();
            cpuset_can_attach();
              mutex_lock(&cpuset_mutex); //waiting

Process C
kernfs_fop_write();
  cgroup_file_write();
    cpuset_write_resmask();
      mutex_lock(&cpuset_mutex); //held
      update_cpumask();
        update_cpumasks_hier();
          rebuild_sched_domains_locked();
            get_online_cpus();
              percpu_down_read(&cpu_hotplug_lock); //waiting

Eliminating deadlock by reversing the locking order for cpuset_mutex and
cpu_hotplug_lock.

Signed-off-by: Prateek Sood <prsood@codeaurora.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-11-27 08:48:10 -08:00
Paul E. McKenney
844ccdd7dc rcu: Eliminate rcu_irq_enter_disabled()
Now that the irq path uses the rcu_nmi_{enter,exit}() algorithm,
rcu_irq_enter() and rcu_irq_exit() may be used from any context.  There is
thus no need for rcu_irq_enter_disabled() and for the checks using it.
This commit therefore eliminates rcu_irq_enter_disabled().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-11-27 08:42:03 -08:00
Paul E. McKenney
51a1fd30f1 rcu: Make ->dynticks_nesting be a simple counter
Now that ->dynticks_nesting counts only process-level dyntick-idle
entry and exit, there is no need for the elaborate segmented counter
with its guard fields and overflow checking.  This commit therefore
makes ->dynticks_nesting be a simple counter.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-11-27 08:42:03 -08:00
Paul E. McKenney
58721f5da4 rcu: Define rcu_irq_{enter,exit}() in terms of rcu_nmi_{enter,exit}()
RCU currently uses two different mechanisms for tracking irqs and NMIs.
This is unnecessary complexity: Given that NMIs can nest and given that
RCU's tracking handles such nesting, the NMI tracking mechanism can also
be used to track irqs.  This commit therefore defines rcu_irq_enter()
in terms of rcu_nmi_enter() and rcu_irq_exit() in terms of rcu_nmi_exit().

Unfortunately, callers must still distinguish between the irq and NMI
functions because additional actions are taken when an irq interrupts
idle or nohz_full usermode execution, and these actions cannot always
be taken from NMI handlers.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-11-27 08:42:03 -08:00
Paul E. McKenney
6136d6e48a rcu: Clamp ->dynticks_nmi_nesting at eqs entry/exit
In preparation for merging dyntick-idle irq handling into the NMI
algorithm, clamp ->dynticks_nmi_nesting value to allow for interrupts
that enter but never leave and vice versa.

It is important that the clamping happen outside of the extended quiescent
state.  Otherwise, there will be short windows where irqs and NMIs fail
to convince RCU to start watching.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-11-27 08:40:10 -08:00
Paul E. McKenney
fd581a91ac rcu: Move rcu_nmi_{enter,exit}() to prepare for consolidation
This is a code-motion-only commit that prepares to define rcu_irq_enter()
in terms of rcu_nmi_enter() and rcu_irq_exit() in terms of rcu_irq_exit().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-11-27 08:40:10 -08:00
Paul E. McKenney
a0eb22bf64 rcu: Reduce dyntick-idle state space
Both extended-quiescent-state entry and exit first update the nesting
counter and then adjust the dyntick-idle state.  This means that there
are four states: (1) Both nesting and dyntick idle indicate idle,
(2) Nesting indicates idle but dyntick idle does not, (3) Nesting indicates
non-idle and dyntick idle does not, and (4) Both nesting and dyntick
idle indicate non-idle.  This commit simplifies the state space by
eliminating #3, reversing the order of updates on exit from extended
quiescent state.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-11-27 08:40:10 -08:00
Paul E. McKenney
2e672ab2d4 rcu: Avoid ->dynticks_nmi_nesting store tearing
NMIs can nest, and store tearing could in theory happen on carries
from one byte to the next.  This commit therefore adds the WRITE_ONCE()
macros preventing this.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-11-27 08:40:09 -08:00
Linus Torvalds
dec0029a59 Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Glexiner:

 - unbreak the irq trigger type check for legacy platforms

 - a handful fixes for ARM GIC v3/4 interrupt controllers

 - a few trivial fixes all over the place

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/matrix: Make - vs ?: Precedence explicit
  irqchip/imgpdc: Use resource_size function on resource object
  irqchip/qcom: Fix u32 comparison with value less than zero
  irqchip/exiu: Fix return value check in exiu_init()
  irqchip/gic-v3-its: Remove artificial dependency on PCI
  irqchip/gic-v4: Add forward definition of struct irq_domain_ops
  irqchip/gic-v3: pr_err() strings should end with newlines
  irqchip/s3c24xx: pr_err() strings should end with newlines
  irqchip/gic-v3: Fix ppi-partitions lookup
  irqchip/gic-v4: Clear IRQ_DISABLE_UNLAZY again if mapping fails
  genirq: Track whether the trigger type has been set
2017-11-26 14:39:20 -08:00
Linus Torvalds
580e3d552d Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Misc fixes: two PMU driver fixes and a memory leak fix"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Fix memory leak triggered by perf --namespace
  perf/x86/intel/uncore: Add event constraint for BDX PCU
  perf/x86/intel: Hide TSX events when RTM is not supported
2017-11-26 13:41:48 -08:00
Linus Torvalds
cd4b5d5d27 Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull static key fix from Ingo Molnar:
 "Fix a boot warning related to bad init ordering of the static keys
  self-test"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  jump_label: Invoke jump_label_test() via early_initcall()
2017-11-26 13:36:54 -08:00
Linus Torvalds
844056fd74 Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:

 - The final conversion of timer wheel timers to timer_setup().

   A few manual conversions and a large coccinelle assisted sweep and
   the removal of the old initialization mechanisms and the related
   code.

 - Remove the now unused VSYSCALL update code

 - Fix permissions of /proc/timer_list. I still need to get rid of that
   file completely

 - Rename a misnomed clocksource function and remove a stale declaration

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
  m68k/macboing: Fix missed timer callback assignment
  treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts
  timer: Remove redundant __setup_timer*() macros
  timer: Pass function down to initialization routines
  timer: Remove unused data arguments from macros
  timer: Switch callback prototype to take struct timer_list * argument
  timer: Pass timer_list pointer to callbacks unconditionally
  Coccinelle: Remove setup_timer.cocci
  timer: Remove setup_*timer() interface
  timer: Remove init_timer() interface
  treewide: setup_timer() -> timer_setup() (2 field)
  treewide: setup_timer() -> timer_setup()
  treewide: init_timer() -> setup_timer()
  treewide: Switch DEFINE_TIMER callbacks to struct timer_list *
  s390: cmm: Convert timers to use timer_setup()
  lightnvm: Convert timers to use timer_setup()
  drivers/net: cris: Convert timers to use timer_setup()
  drm/vc4: Convert timers to use timer_setup()
  block/laptop_mode: Convert timers to use timer_setup()
  net/atm/mpc: Avoid open-coded assignment of timer callback function
  ...
2017-11-25 08:37:16 -10:00
Kees Cook
75f1133873 genirq/matrix: Make - vs ?: Precedence explicit
Noticed with a Clang build. This improves the readability of the ?:
expression, as it has lower precedence than the - expression. Show
explicitly that - is evaluated first.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20171122205645.GA27125@beast
2017-11-23 20:09:31 +01:00
David S. Miller
e4be7baba8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2017-11-23

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Several BPF offloading fixes, from Jakub. Among others:

    - Limit offload to cls_bpf and XDP program types only.
    - Move device validation into the driver and don't make
      any assumptions about the device in the classifier due
      to shared blocks semantics.
    - Don't pass offloaded XDP program into the driver when
      it should be run in native XDP instead. Offloaded ones
      are not JITed for the host in such cases.
    - Don't destroy device offload state when moved to
      another namespace.
    - Revert dumping offload info into user space for now,
      since ifindex alone is not sufficient. This will be
      redone properly for bpf-next tree.

2) Fix test_verifier to avoid using bpf_probe_write_user()
   helper in test cases, since it's dumping a warning into
   kernel log which may confuse users when only running tests.
   Switch to use bpf_trace_printk() instead, from Yonghong.

3) Several fixes for correcting ARG_CONST_SIZE_OR_ZERO semantics
   before it becomes uabi, from Gianluca. More specifically:

    - Add a type ARG_PTR_TO_MEM_OR_NULL that is used only
      by bpf_csum_diff(), where the argument is either a
      valid pointer or NULL. The subsequent ARG_CONST_SIZE_OR_ZERO
      then enforces a valid pointer in case of non-0 size
      or a valid pointer or NULL in case of size 0. Given
      that, the semantics for ARG_PTR_TO_MEM in combination
      with ARG_CONST_SIZE_OR_ZERO are now such that in case
      of size 0, the pointer must always be valid and cannot
      be NULL. This fix in semantics allows for bpf_probe_read()
      to drop the recently added size == 0 check in the helper
      that would become part of uabi otherwise once released.
      At the same time we can then fix bpf_probe_read_str() and
      bpf_perf_event_output() to use ARG_CONST_SIZE_OR_ZERO
      instead of ARG_CONST_SIZE in order to fix recently
      reported issues by Arnaldo et al, where LLVM optimizes
      two boundary checks into a single one for unknown
      variables where the verifier looses track of the variable
      bounds and thus rejects valid programs otherwise.

4) A fix for the verifier for the case when it detects
   comparison of two constants where the branch is guaranteed
   to not be taken at runtime. Verifier will rightfully prune
   the exploration of such paths, but we still pass the program
   to JITs, where they would complain about using reserved
   fields, etc. Track such dead instructions and sanitize
   them with mov r0,r0. Rejection is not possible since LLVM
   may generate them for valid C code and doesn't do as much
   data flow analysis as verifier. For bpf-next we might
   implement removal of such dead code and adjust branches
   instead. Fix from Alexei.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-24 02:33:01 +09:00
Thomas Gleixner
866c9b94ef - final batch of "non trivial" timer conversions (multi-tree dependencies,
things Coccinelle couldn't handle, etc).
 - treewide conversions via Coccinelle, in 4 steps:
   - DEFINE_TIMER() functions converted to struct timer_list * argument
   - init_timer() -> setup_timer()
   - setup_timer() -> timer_setup()
   - setup_timer() -> timer_setup() (with a single embedded structure)
 - deprecated timer API removals (init_timer(), setup_*timer())
 - finalization of new API (remove global casts)
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 Comment: Kees Cook <kees@outflux.net>
 
 iQIcBAABCgAGBQJaFMcSAAoJEIly9N/cbcAmsToQAIrAIWJIj/buzoXgvsesBWE0
 B+l7fZr4q0xwx7gU1FEBcNu3MTJz3GQgpfSD5x5HhXX4vxwVQJWnYIkQvvM2YjVG
 d/wgwqPu24hIyU2i3WX584K+r7uwhN85eL8CN/YB264bTnMc+aZAIOqY2jwLRr1u
 uSa7JNCyjEpENIiZ3zWgojGu/izCoW4KBzKOpWWqrfrfGgmx+ImFlLgneSmgOhg4
 9y1pqqifYbMx313ZWfln4XVdiQwuqG7weE6oPZ7j9ypM4UX1lQUG+SdZmYYvBHcV
 /LopB7zGwbbCoUDwzDTz4a/xYobteXaqEkFlwFAqsGtjqvYks+n0IKgzcKRvOF6R
 O9j4lWPK87B1uIKtkO/W0bJs5KA1w273U+mUvjEH+fTyjvpAJLkMzpEP3NxM3BJ4
 ilYXNNvfFaT3lslOhyaces54Q2eAVzodL4zcaeKfPKxrdv0V58nOYKUqFpIKBp7n
 JKcZm58xTiLcpqT/Zg31in83kBMg499LAorjvY1y68GjFtXQ0YBNA4EaxDZD4z56
 /N2tQarAu7xmo1VTSM+NVDY4X5H122XINIcpPRQ/qEF9usQDoBY1N8vusUis05R9
 IKvn+cpS20dLYyPZUgV5zHx+HNjIxUoANiQTHRLI7HvADUDXCcMXM4CZoKdCWXNG
 cf6CGbhH9hOIAQpUD154
 =Tj+I
 -----END PGP SIGNATURE-----

Merge tag 'for-linus-timers-conversion-final-v4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux into timers/urgent

Pull the last batch of manual timer conversions from Kees Cook:

 - final batch of "non trivial" timer conversions (multi-tree dependencies,
   things Coccinelle couldn't handle, etc).

 - treewide conversions via Coccinelle, in 4 steps:
   - DEFINE_TIMER() functions converted to struct timer_list * argument
   - init_timer() -> setup_timer()
   - setup_timer() -> timer_setup()
   - setup_timer() -> timer_setup() (with a single embedded structure)

 - deprecated timer API removals (init_timer(), setup_*timer())

 - finalization of new API (remove global casts)
2017-11-23 16:29:05 +01:00
Alexei Starovoitov
c131187db2 bpf: fix branch pruning logic
when the verifier detects that register contains a runtime constant
and it's compared with another constant it will prune exploration
of the branch that is guaranteed not to be taken at runtime.
This is all correct, but malicious program may be constructed
in such a way that it always has a constant comparison and
the other branch is never taken under any conditions.
In this case such path through the program will not be explored
by the verifier. It won't be taken at run-time either, but since
all instructions are JITed the malicious program may cause JITs
to complain about using reserved fields, etc.
To fix the issue we have to track the instructions explored by
the verifier and sanitize instructions that are dead at run time
with NOPs. We cannot reject such dead code, since llvm generates
it for valid C code, since it doesn't do as much data flow
analysis as the verifier does.

Fixes: 17a5267067 ("bpf: verifier (add verifier core)")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-23 10:56:35 +01:00
Gianluca Borello
a60dd35d2e bpf: change bpf_perf_event_output arg5 type to ARG_CONST_SIZE_OR_ZERO
Commit 9fd29c08e5 ("bpf: improve verifier ARG_CONST_SIZE_OR_ZERO
semantics") relaxed the treatment of ARG_CONST_SIZE_OR_ZERO due to the way
the compiler generates optimized BPF code when checking boundaries of an
argument from C code. A typical example of this optimized code can be
generated using the bpf_perf_event_output helper when operating on variable
memory:

/* len is a generic scalar */
if (len > 0 && len <= 0x7fff)
        bpf_perf_event_output(ctx, &perf_map, 0, buf, len);

110: (79) r5 = *(u64 *)(r10 -40)
111: (bf) r1 = r5
112: (07) r1 += -1
113: (25) if r1 > 0x7ffe goto pc+6
114: (bf) r1 = r6
115: (18) r2 = 0xffff94e5f166c200
117: (b7) r3 = 0
118: (bf) r4 = r7
119: (85) call bpf_perf_event_output#25
R5 min value is negative, either use unsigned or 'var &= const'

With this code, the verifier loses track of the variable.

Replacing arg5 with ARG_CONST_SIZE_OR_ZERO is thus desirable since it
avoids this quite common case which leads to usability issues, and the
compiler generates code that the verifier can more easily test:

if (len <= 0x7fff)
        bpf_perf_event_output(ctx, &perf_map, 0, buf, len);

or

bpf_perf_event_output(ctx, &perf_map, 0, buf, len & 0x7fff);

No changes to the bpf_perf_event_output helper are necessary since it can
handle a case where size is 0, and an empty frame is pushed.

Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Gianluca Borello <g.borello@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-22 21:40:54 +01:00
Gianluca Borello
5c4e120174 bpf: change bpf_probe_read_str arg2 type to ARG_CONST_SIZE_OR_ZERO
Commit 9fd29c08e5 ("bpf: improve verifier ARG_CONST_SIZE_OR_ZERO
semantics") relaxed the treatment of ARG_CONST_SIZE_OR_ZERO due to the way
the compiler generates optimized BPF code when checking boundaries of an
argument from C code. A typical example of this optimized code can be
generated using the bpf_probe_read_str helper when operating on variable
memory:

/* len is a generic scalar */
if (len > 0 && len <= 0x7fff)
        bpf_probe_read_str(p, len, s);

251: (79) r1 = *(u64 *)(r10 -88)
252: (07) r1 += -1
253: (25) if r1 > 0x7ffe goto pc-42
254: (bf) r1 = r7
255: (79) r2 = *(u64 *)(r10 -88)
256: (bf) r8 = r4
257: (85) call bpf_probe_read_str#45
R2 min value is negative, either use unsigned or 'var &= const'

With this code, the verifier loses track of the variable.

Replacing arg2 with ARG_CONST_SIZE_OR_ZERO is thus desirable since it
avoids this quite common case which leads to usability issues, and the
compiler generates code that the verifier can more easily test:

if (len <= 0x7fff)
        bpf_probe_read_str(p, len, s);

or

bpf_probe_read_str(p, len & 0x7fff, s);

No changes to the bpf_probe_read_str helper are necessary since
strncpy_from_unsafe itself immediately returns if the size passed is 0.

Signed-off-by: Gianluca Borello <g.borello@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-22 21:40:54 +01:00
Gianluca Borello
eb33f2cca4 bpf: remove explicit handling of 0 for arg2 in bpf_probe_read
Commit 9c019e2bc4 ("bpf: change helper bpf_probe_read arg2 type to
ARG_CONST_SIZE_OR_ZERO") changed arg2 type to ARG_CONST_SIZE_OR_ZERO to
simplify writing bpf programs by taking advantage of the new semantics
introduced for ARG_CONST_SIZE_OR_ZERO which allows <!NULL, 0> arguments.

In order to prevent the helper from actually passing a NULL pointer to
probe_kernel_read, which can happen when <NULL, 0> is passed to the helper,
the commit also introduced an explicit check against size == 0.

After the recent introduction of the ARG_PTR_TO_MEM_OR_NULL type,
bpf_probe_read can not receive a pair of <NULL, 0> arguments anymore, thus
the check is not needed anymore and can be removed, since probe_kernel_read
can correctly handle a <!NULL, 0> call. This also fixes the semantics of
the helper before it gets officially released and bpf programs start
relying on this check.

Fixes: 9c019e2bc4 ("bpf: change helper bpf_probe_read arg2 type to ARG_CONST_SIZE_OR_ZERO")
Signed-off-by: Gianluca Borello <g.borello@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-22 21:40:54 +01:00
Gianluca Borello
db1ac4964f bpf: introduce ARG_PTR_TO_MEM_OR_NULL
With the current ARG_PTR_TO_MEM/ARG_PTR_TO_UNINIT_MEM semantics, an helper
argument can be NULL when the next argument type is ARG_CONST_SIZE_OR_ZERO
and the verifier can prove the value of this next argument is 0. However,
most helpers are just interested in handling <!NULL, 0>, so forcing them to
deal with <NULL, 0> makes the implementation of those helpers more
complicated for no apparent benefits, requiring them to explicitly handle
those corner cases with checks that bpf programs could start relying upon,
preventing the possibility of removing them later.

Solve this by making ARG_PTR_TO_MEM/ARG_PTR_TO_UNINIT_MEM never accept NULL
even when ARG_CONST_SIZE_OR_ZERO is set, and introduce a new argument type
ARG_PTR_TO_MEM_OR_NULL to explicitly deal with the NULL case.

Currently, the only helper that needs this is bpf_csum_diff_proto(), so
change arg1 and arg3 to this new type as well.

Also add a new battery of tests that explicitly test the
!ARG_PTR_TO_MEM_OR_NULL combination: all the current ones testing the
various <NULL, 0> variations are focused on bpf_csum_diff, so cover also
other helpers.

Signed-off-by: Gianluca Borello <g.borello@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-22 21:40:54 +01:00
Kees Cook
841b86f328 treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts
With all callbacks converted, and the timer callback prototype
switched over, the TIMER_FUNC_TYPE cast is no longer needed,
so remove it. Conversion was done with the following scripts:

    perl -pi -e 's|\(TIMER_FUNC_TYPE\)||g' \
        $(git grep TIMER_FUNC_TYPE | cut -d: -f1 | sort -u)

    perl -pi -e 's|\(TIMER_DATA_TYPE\)||g' \
        $(git grep TIMER_DATA_TYPE | cut -d: -f1 | sort -u)

The now unused macros are also dropped from include/linux/timer.h.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-11-21 16:35:54 -08:00
Kees Cook
188665b2d6 timer: Pass function down to initialization routines
In preparation for removing more macros, pass the function down to the
initialization routines instead of doing it in macros.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
2017-11-21 15:57:14 -08:00
Kees Cook
354b46b1a0 timer: Switch callback prototype to take struct timer_list * argument
Since all callbacks have been converted, we can switch the core
prototype to "struct timer_list *" now too.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
2017-11-21 15:57:13 -08:00
Kees Cook
c1eba5bcb6 timer: Pass timer_list pointer to callbacks unconditionally
Now that all timer callbacks are already taking their struct timer_list
pointer as the callback argument, just do this unconditionally and remove
the .data field.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
2017-11-21 15:57:12 -08:00
Kees Cook
e99e88a9d2 treewide: setup_timer() -> timer_setup()
This converts all remaining cases of the old setup_timer() API into using
timer_setup(), where the callback argument is the structure already
holding the struct timer_list. These should have no behavioral changes,
since they just change which pointer is passed into the callback with
the same available pointers after conversion. It handles the following
examples, in addition to some other variations.

Casting from unsigned long:

    void my_callback(unsigned long data)
    {
        struct something *ptr = (struct something *)data;
    ...
    }
    ...
    setup_timer(&ptr->my_timer, my_callback, ptr);

and forced object casts:

    void my_callback(struct something *ptr)
    {
    ...
    }
    ...
    setup_timer(&ptr->my_timer, my_callback, (unsigned long)ptr);

become:

    void my_callback(struct timer_list *t)
    {
        struct something *ptr = from_timer(ptr, t, my_timer);
    ...
    }
    ...
    timer_setup(&ptr->my_timer, my_callback, 0);

Direct function assignments:

    void my_callback(unsigned long data)
    {
        struct something *ptr = (struct something *)data;
    ...
    }
    ...
    ptr->my_timer.function = my_callback;

have a temporary cast added, along with converting the args:

    void my_callback(struct timer_list *t)
    {
        struct something *ptr = from_timer(ptr, t, my_timer);
    ...
    }
    ...
    ptr->my_timer.function = (TIMER_FUNC_TYPE)my_callback;

And finally, callbacks without a data assignment:

    void my_callback(unsigned long data)
    {
    ...
    }
    ...
    setup_timer(&ptr->my_timer, my_callback, 0);

have their argument renamed to verify they're unused during conversion:

    void my_callback(struct timer_list *unused)
    {
    ...
    }
    ...
    timer_setup(&ptr->my_timer, my_callback, 0);

The conversion is done with the following Coccinelle script:

spatch --very-quiet --all-includes --include-headers \
	-I ./arch/x86/include -I ./arch/x86/include/generated \
	-I ./include -I ./arch/x86/include/uapi \
	-I ./arch/x86/include/generated/uapi -I ./include/uapi \
	-I ./include/generated/uapi --include ./include/linux/kconfig.h \
	--dir . \
	--cocci-file ~/src/data/timer_setup.cocci

@fix_address_of@
expression e;
@@

 setup_timer(
-&(e)
+&e
 , ...)

// Update any raw setup_timer() usages that have a NULL callback, but
// would otherwise match change_timer_function_usage, since the latter
// will update all function assignments done in the face of a NULL
// function initialization in setup_timer().
@change_timer_function_usage_NULL@
expression _E;
identifier _timer;
type _cast_data;
@@

(
-setup_timer(&_E->_timer, NULL, _E);
+timer_setup(&_E->_timer, NULL, 0);
|
-setup_timer(&_E->_timer, NULL, (_cast_data)_E);
+timer_setup(&_E->_timer, NULL, 0);
|
-setup_timer(&_E._timer, NULL, &_E);
+timer_setup(&_E._timer, NULL, 0);
|
-setup_timer(&_E._timer, NULL, (_cast_data)&_E);
+timer_setup(&_E._timer, NULL, 0);
)

@change_timer_function_usage@
expression _E;
identifier _timer;
struct timer_list _stl;
identifier _callback;
type _cast_func, _cast_data;
@@

(
-setup_timer(&_E->_timer, _callback, _E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, &_callback, _E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, _callback, (_cast_data)_E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, &_callback, (_cast_data)_E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, (_cast_func)_callback, _E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, (_cast_func)&_callback, _E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, (_cast_func)_callback, (_cast_data)_E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, (_cast_func)&_callback, (_cast_data)_E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, (_cast_data)_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, (_cast_data)&_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, &_callback, (_cast_data)_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, &_callback, (_cast_data)&_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)&_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)&_E);
+timer_setup(&_E._timer, _callback, 0);
|
 _E->_timer@_stl.function = _callback;
|
 _E->_timer@_stl.function = &_callback;
|
 _E->_timer@_stl.function = (_cast_func)_callback;
|
 _E->_timer@_stl.function = (_cast_func)&_callback;
|
 _E._timer@_stl.function = _callback;
|
 _E._timer@_stl.function = &_callback;
|
 _E._timer@_stl.function = (_cast_func)_callback;
|
 _E._timer@_stl.function = (_cast_func)&_callback;
)

// callback(unsigned long arg)
@change_callback_handle_cast
 depends on change_timer_function_usage@
identifier change_timer_function_usage._callback;
identifier change_timer_function_usage._timer;
type _origtype;
identifier _origarg;
type _handletype;
identifier _handle;
@@

 void _callback(
-_origtype _origarg
+struct timer_list *t
 )
 {
(
	... when != _origarg
	_handletype *_handle =
-(_handletype *)_origarg;
+from_timer(_handle, t, _timer);
	... when != _origarg
|
	... when != _origarg
	_handletype *_handle =
-(void *)_origarg;
+from_timer(_handle, t, _timer);
	... when != _origarg
|
	... when != _origarg
	_handletype *_handle;
	... when != _handle
	_handle =
-(_handletype *)_origarg;
+from_timer(_handle, t, _timer);
	... when != _origarg
|
	... when != _origarg
	_handletype *_handle;
	... when != _handle
	_handle =
-(void *)_origarg;
+from_timer(_handle, t, _timer);
	... when != _origarg
)
 }

// callback(unsigned long arg) without existing variable
@change_callback_handle_cast_no_arg
 depends on change_timer_function_usage &&
                     !change_callback_handle_cast@
identifier change_timer_function_usage._callback;
identifier change_timer_function_usage._timer;
type _origtype;
identifier _origarg;
type _handletype;
@@

 void _callback(
-_origtype _origarg
+struct timer_list *t
 )
 {
+	_handletype *_origarg = from_timer(_origarg, t, _timer);
+
	... when != _origarg
-	(_handletype *)_origarg
+	_origarg
	... when != _origarg
 }

// Avoid already converted callbacks.
@match_callback_converted
 depends on change_timer_function_usage &&
            !change_callback_handle_cast &&
	    !change_callback_handle_cast_no_arg@
identifier change_timer_function_usage._callback;
identifier t;
@@

 void _callback(struct timer_list *t)
 { ... }

// callback(struct something *handle)
@change_callback_handle_arg
 depends on change_timer_function_usage &&
	    !match_callback_converted &&
            !change_callback_handle_cast &&
            !change_callback_handle_cast_no_arg@
identifier change_timer_function_usage._callback;
identifier change_timer_function_usage._timer;
type _handletype;
identifier _handle;
@@

 void _callback(
-_handletype *_handle
+struct timer_list *t
 )
 {
+	_handletype *_handle = from_timer(_handle, t, _timer);
	...
 }

// If change_callback_handle_arg ran on an empty function, remove
// the added handler.
@unchange_callback_handle_arg
 depends on change_timer_function_usage &&
	    change_callback_handle_arg@
identifier change_timer_function_usage._callback;
identifier change_timer_function_usage._timer;
type _handletype;
identifier _handle;
identifier t;
@@

 void _callback(struct timer_list *t)
 {
-	_handletype *_handle = from_timer(_handle, t, _timer);
 }

// We only want to refactor the setup_timer() data argument if we've found
// the matching callback. This undoes changes in change_timer_function_usage.
@unchange_timer_function_usage
 depends on change_timer_function_usage &&
            !change_callback_handle_cast &&
            !change_callback_handle_cast_no_arg &&
	    !change_callback_handle_arg@
expression change_timer_function_usage._E;
identifier change_timer_function_usage._timer;
identifier change_timer_function_usage._callback;
type change_timer_function_usage._cast_data;
@@

(
-timer_setup(&_E->_timer, _callback, 0);
+setup_timer(&_E->_timer, _callback, (_cast_data)_E);
|
-timer_setup(&_E._timer, _callback, 0);
+setup_timer(&_E._timer, _callback, (_cast_data)&_E);
)

// If we fixed a callback from a .function assignment, fix the
// assignment cast now.
@change_timer_function_assignment
 depends on change_timer_function_usage &&
            (change_callback_handle_cast ||
             change_callback_handle_cast_no_arg ||
             change_callback_handle_arg)@
expression change_timer_function_usage._E;
identifier change_timer_function_usage._timer;
identifier change_timer_function_usage._callback;
type _cast_func;
typedef TIMER_FUNC_TYPE;
@@

(
 _E->_timer.function =
-_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E->_timer.function =
-&_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E->_timer.function =
-(_cast_func)_callback;
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E->_timer.function =
-(_cast_func)&_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E._timer.function =
-_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E._timer.function =
-&_callback;
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E._timer.function =
-(_cast_func)_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E._timer.function =
-(_cast_func)&_callback
+(TIMER_FUNC_TYPE)_callback
 ;
)

// Sometimes timer functions are called directly. Replace matched args.
@change_timer_function_calls
 depends on change_timer_function_usage &&
            (change_callback_handle_cast ||
             change_callback_handle_cast_no_arg ||
             change_callback_handle_arg)@
expression _E;
identifier change_timer_function_usage._timer;
identifier change_timer_function_usage._callback;
type _cast_data;
@@

 _callback(
(
-(_cast_data)_E
+&_E->_timer
|
-(_cast_data)&_E
+&_E._timer
|
-_E
+&_E->_timer
)
 )

// If a timer has been configured without a data argument, it can be
// converted without regard to the callback argument, since it is unused.
@match_timer_function_unused_data@
expression _E;
identifier _timer;
identifier _callback;
@@

(
-setup_timer(&_E->_timer, _callback, 0);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, _callback, 0L);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, _callback, 0UL);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, 0);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, 0L);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, 0UL);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_timer, _callback, 0);
+timer_setup(&_timer, _callback, 0);
|
-setup_timer(&_timer, _callback, 0L);
+timer_setup(&_timer, _callback, 0);
|
-setup_timer(&_timer, _callback, 0UL);
+timer_setup(&_timer, _callback, 0);
|
-setup_timer(_timer, _callback, 0);
+timer_setup(_timer, _callback, 0);
|
-setup_timer(_timer, _callback, 0L);
+timer_setup(_timer, _callback, 0);
|
-setup_timer(_timer, _callback, 0UL);
+timer_setup(_timer, _callback, 0);
)

@change_callback_unused_data
 depends on match_timer_function_unused_data@
identifier match_timer_function_unused_data._callback;
type _origtype;
identifier _origarg;
@@

 void _callback(
-_origtype _origarg
+struct timer_list *unused
 )
 {
	... when != _origarg
 }

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-11-21 15:57:07 -08:00
Kees Cook
b9eaf18722 treewide: init_timer() -> setup_timer()
This mechanically converts all remaining cases of ancient open-coded timer
setup with the old setup_timer() API, which is the first step in timer
conversions. This has no behavioral changes, since it ultimately just
changes the order of assignment to fields of struct timer_list when
finding variations of:

    init_timer(&t);
    f.function = timer_callback;
    t.data = timer_callback_arg;

to be converted into:

    setup_timer(&t, timer_callback, timer_callback_arg);

The conversion is done with the following Coccinelle script, which
is an improved version of scripts/cocci/api/setup_timer.cocci, in the
following ways:
 - assignments-before-init_timer() cases
 - limit the .data case removal to the specific struct timer_list instance
 - handling calls by dereference (timer->field vs timer.field)

spatch --very-quiet --all-includes --include-headers \
	-I ./arch/x86/include -I ./arch/x86/include/generated \
	-I ./include -I ./arch/x86/include/uapi \
	-I ./arch/x86/include/generated/uapi -I ./include/uapi \
	-I ./include/generated/uapi --include ./include/linux/kconfig.h \
	--dir . \
	--cocci-file ~/src/data/setup_timer.cocci

@fix_address_of@
expression e;
@@

 init_timer(
-&(e)
+&e
 , ...)

// Match the common cases first to avoid Coccinelle parsing loops with
// "... when" clauses.

@match_immediate_function_data_after_init_timer@
expression e, func, da;
@@

-init_timer
+setup_timer
 ( \(&e\|e\)
+, func, da
 );
(
-\(e.function\|e->function\) = func;
-\(e.data\|e->data\) = da;
|
-\(e.data\|e->data\) = da;
-\(e.function\|e->function\) = func;
)

@match_immediate_function_data_before_init_timer@
expression e, func, da;
@@

(
-\(e.function\|e->function\) = func;
-\(e.data\|e->data\) = da;
|
-\(e.data\|e->data\) = da;
-\(e.function\|e->function\) = func;
)
-init_timer
+setup_timer
 ( \(&e\|e\)
+, func, da
 );

@match_function_and_data_after_init_timer@
expression e, e2, e3, e4, e5, func, da;
@@

-init_timer
+setup_timer
 ( \(&e\|e\)
+, func, da
 );
 ... when != func = e2
     when != da = e3
(
-e.function = func;
... when != da = e4
-e.data = da;
|
-e->function = func;
... when != da = e4
-e->data = da;
|
-e.data = da;
... when != func = e5
-e.function = func;
|
-e->data = da;
... when != func = e5
-e->function = func;
)

@match_function_and_data_before_init_timer@
expression e, e2, e3, e4, e5, func, da;
@@
(
-e.function = func;
... when != da = e4
-e.data = da;
|
-e->function = func;
... when != da = e4
-e->data = da;
|
-e.data = da;
... when != func = e5
-e.function = func;
|
-e->data = da;
... when != func = e5
-e->function = func;
)
... when != func = e2
    when != da = e3
-init_timer
+setup_timer
 ( \(&e\|e\)
+, func, da
 );

@r1 exists@
expression t;
identifier f;
position p;
@@

f(...) { ... when any
  init_timer@p(\(&t\|t\))
  ... when any
}

@r2 exists@
expression r1.t;
identifier g != r1.f;
expression e8;
@@

g(...) { ... when any
  \(t.data\|t->data\) = e8
  ... when any
}

// It is dangerous to use setup_timer if data field is initialized
// in another function.
@script:python depends on r2@
p << r1.p;
@@

cocci.include_match(False)

@r3@
expression r1.t, func, e7;
position r1.p;
@@

(
-init_timer@p(&t);
+setup_timer(&t, func, 0UL);
... when != func = e7
-t.function = func;
|
-t.function = func;
... when != func = e7
-init_timer@p(&t);
+setup_timer(&t, func, 0UL);
|
-init_timer@p(t);
+setup_timer(t, func, 0UL);
... when != func = e7
-t->function = func;
|
-t->function = func;
... when != func = e7
-init_timer@p(t);
+setup_timer(t, func, 0UL);
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-11-21 15:57:06 -08:00
Kees Cook
24ed960abf treewide: Switch DEFINE_TIMER callbacks to struct timer_list *
This changes all DEFINE_TIMER() callbacks to use a struct timer_list
pointer instead of unsigned long. Since the data argument has already been
removed, none of these callbacks are using their argument currently, so
this renames the argument to "unused".

Done using the following semantic patch:

@match_define_timer@
declarer name DEFINE_TIMER;
identifier _timer, _callback;
@@

 DEFINE_TIMER(_timer, _callback);

@change_callback depends on match_define_timer@
identifier match_define_timer._callback;
type _origtype;
identifier _origarg;
@@

 void
-_callback(_origtype _origarg)
+_callback(struct timer_list *unused)
 { ... }

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-11-21 15:57:05 -08:00
Linus Torvalds
11ca75d2d6 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk
Pull printk updates from Petr Mladek:

 - print the warning about dropped messages on consoles on a separate
   line.   It makes it more legible.

 - one typo fix and small code clean up.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
  added new line symbol after warning about dropped messages
  printk: fix typo in printk_safe.c
  printk: simplify no_printk()
2017-11-21 05:28:13 -10:00
Jakub Kicinski
1ee640095f bpf: revert report offload info to user space
This reverts commit bd601b6ada ("bpf: report offload info to user
space").  The ifindex by itself is not sufficient, we should provide
information on which network namespace this ifindex belongs to.
After considering some options we concluded that it's best to just
remove this API for now, and rework it in -next.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21 00:37:35 +01:00
Jakub Kicinski
62c71b45e8 bpf: offload: ignore namespace moves
We are currently destroying the device offload state when device
moves to another net namespace.  This doesn't break with current
NFP code, because offload state is not used on program removal,
but it's not correct behaviour.

Ignore the device unregister notifications on namespace move.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21 00:37:35 +01:00
Jakub Kicinski
479321e9c3 bpf: turn bpf_prog_get_type() into a wrapper
bpf_prog_get_type() is identical to bpf_prog_get_type_dev(),
with false passed as attach_drv.  Instead of keeping it as
an exported symbol turn it into static inline wrapper.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21 00:37:35 +01:00
Jakub Kicinski
288b3de55a bpf: offload: move offload device validation out to the drivers
With TC shared block changes we can't depend on correct netdev
pointer being available in cls_bpf.  Move the device validation
to the driver.  Core will only make sure that offloaded programs
are always attached in the driver (or in HW by the driver).  We
trust that drivers which implement offload callbacks will perform
necessary checks.

Moving the checks to the driver is generally a useful thing,
in practice the check should be against a switchdev instance,
not a netdev, given that most ASICs will probably allow using
the same program on many ports.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21 00:37:35 +01:00
Jakub Kicinski
1f6f4cb7ba bpf: offload: rename the ifindex field
bpf_target_prog seems long and clunky, rename it to prog_ifindex.
We don't want to call this field just ifindex, because maps
may need a similar field in the future and bpf_attr members for
programs and maps are unnamed.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21 00:37:35 +01:00
Jakub Kicinski
649f11dcd1 bpf: offload: limit offload to cls_bpf and xdp programs only
We are currently only allowing attachment of device-bound
cls_bpf and XDP programs.  Make this restriction explicit in
the BPF offload code.  This way we can potentially reuse the
ifindex field in the future.

Since XDP and cls_bpf programs can only be loaded by admin,
we can drop the explicit capability check from offload code.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21 00:37:35 +01:00
Jakub Kicinski
13a9c48a85 bpf: offload: add comment warning developers about double destroy
Offload state may get destroyed either because the device for which
it was constructed is going away, or because the refcount of bpf
program itself has reached 0.  In both of those cases we will call
__bpf_prog_offload_destroy() to unlink the offload from the device.
We may in fact call it twice, which works just fine, but we should
make clear this is intended and caution others trying to extend the
function.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21 00:37:35 +01:00
Marcos Paulo de Souza
1690102de5 blktrace: Use blk_trace_bio_get_cgid inside blk_add_trace_bio
We always pass in blk_trace_bio_get_cgid(q, bio) to blk_add_trace_bio().
Since both are readily available in the function already, kill the
argument.

Signed-off-by: Marcos Paulo de Souza <marcos.souza.org@gmail.com>

Rewrote commit message.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-19 12:37:26 -07:00
Linus Torvalds
fa7f578076 Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:

 - a bit more MM

 - procfs updates

 - dynamic-debug fixes

 - lib/ updates

 - checkpatch

 - epoll

 - nilfs2

 - signals

 - rapidio

 - PID management cleanup and optimization

 - kcov updates

 - sysvipc updates

 - quite a few misc things all over the place

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (94 commits)
  EXPERT Kconfig menu: fix broken EXPERT menu
  include/asm-generic/topology.h: remove unused parent_node() macro
  arch/tile/include/asm/topology.h: remove unused parent_node() macro
  arch/sparc/include/asm/topology_64.h: remove unused parent_node() macro
  arch/sh/include/asm/topology.h: remove unused parent_node() macro
  arch/ia64/include/asm/topology.h: remove unused parent_node() macro
  drivers/pcmcia/sa1111_badge4.c: avoid unused function warning
  mm: add infrastructure for get_user_pages_fast() benchmarking
  sysvipc: make get_maxid O(1) again
  sysvipc: properly name ipc_addid() limit parameter
  sysvipc: duplicate lock comments wrt ipc_addid()
  sysvipc: unteach ids->next_id for !CHECKPOINT_RESTORE
  initramfs: use time64_t timestamps
  drivers/watchdog: make use of devm_register_reboot_notifier()
  kernel/reboot.c: add devm_register_reboot_notifier()
  kcov: update documentation
  Makefile: support flag -fsanitizer-coverage=trace-cmp
  kcov: support comparison operands collection
  kcov: remove pointless current != NULL check
  kernel/panic.c: add TAINT_AUX
  ...
2017-11-17 16:56:17 -08:00
Andrey Smirnov
2d8364bae4 kernel/reboot.c: add devm_register_reboot_notifier()
Add devm_* wrapper around register_reboot_notifier to simplify device
specific reboot notifier registration/unregistration.

[akpm@linux-foundation.org: move `struct device' forward decl to top-of-file]
Link: http://lkml.kernel.org/r/20170320171753.1705-1-andrew.smirnov@gmail.com
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:04 -08:00
Victor Chibotaru
ded97d2c2b kcov: support comparison operands collection
Enables kcov to collect comparison operands from instrumented code.
This is done by using Clang's -fsanitize=trace-cmp instrumentation
(currently not available for GCC).

The comparison operands help a lot in fuzz testing.  E.g.  they are used
in Syzkaller to cover the interiors of conditional statements with way
less attempts and thus make previously unreachable code reachable.

To allow separate collection of coverage and comparison operands two
different work modes are implemented.  Mode selection is now done via a
KCOV_ENABLE ioctl call with corresponding argument value.

Link: http://lkml.kernel.org/r/20171011095459.70721-1-glider@google.com
Signed-off-by: Victor Chibotaru <tchibo@google.com>
Signed-off-by: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Popov <alex.popov@linux.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: <syzkaller@googlegroups.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:04 -08:00
Andrey Ryabinin
fcf4edac04 kcov: remove pointless current != NULL check
__sanitizer_cov_trace_pc() is a hot code, so it's worth to remove
pointless '!current' check.  Current is never NULL.

Link: http://lkml.kernel.org/r/20170929162221.32500-1-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:04 -08:00
Borislav Petkov
4efb442cc1 kernel/panic.c: add TAINT_AUX
This is the gist of a patch which we've been forward-porting in our
kernels for a long time now and it probably would make a good sense to
have such TAINT_AUX flag upstream which can be used by each distro etc,
how they see fit.  This way, we won't need to forward-port a distro-only
version indefinitely.

Add an auxiliary taint flag to be used by distros and others.  This
obviates the need to forward-port whatever internal solutions people
have in favor of a single flag which they can map arbitrarily to a
definition of their pleasing.

The "X" mnemonic could also mean eXternal, which would be taint from a
distro or something else but not the upstream kernel.  We will use it to
mark modules for which we don't provide support.  I.e., a really
eXternal module.

Link: http://lkml.kernel.org/r/20170911134533.dp5mtyku5bongx4c@pd.tnic
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:04 -08:00
Gargi Sharma
e8cfbc245e pid: remove pidhash
pidhash is no longer required as all the information can be looked up
from idr tree.  nr_hashed represented the number of pids that had been
hashed.  Since, nr_hashed and PIDNS_HASH_ADDING are no longer relevant,
it has been renamed to pid_allocated and PIDNS_ADDING respectively.

[gs051095@gmail.com: v6]
  Link: http://lkml.kernel.org/r/1507760379-21662-3-git-send-email-gs051095@gmail.com
Link: http://lkml.kernel.org/r/1507583624-22146-3-git-send-email-gs051095@gmail.com
Signed-off-by: Gargi Sharma <gs051095@gmail.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Tested-by: Tony Luck <tony.luck@intel.com>	[ia64]
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:04 -08:00
Gargi Sharma
95846ecf9d pid: replace pid bitmap implementation with IDR API
Patch series "Replacing PID bitmap implementation with IDR API", v4.

This series replaces kernel bitmap implementation of PID allocation with
IDR API.  These patches are written to simplify the kernel by replacing
custom code with calls to generic code.

The following are the stats for pid and pid_namespace object files
before and after the replacement.  There is a noteworthy change between
the IDR and bitmap implementation.

Before
   text       data        bss        dec        hex    filename
   8447       3894         64      12405       3075    kernel/pid.o
After
   text       data        bss        dec        hex    filename
   3397        304          0       3701        e75    kernel/pid.o

Before
   text       data        bss        dec        hex    filename
   5692       1842        192       7726       1e2e    kernel/pid_namespace.o
After
   text       data        bss        dec        hex    filename
   2854        216         16       3086        c0e    kernel/pid_namespace.o

The following are the stats for ps, pstree and calling readdir on /proc
for 10,000 processes.

ps:
        With IDR API    With bitmap
real    0m1.479s        0m2.319s
user    0m0.070s        0m0.060s
sys     0m0.289s        0m0.516s

pstree:
        With IDR API    With bitmap
real    0m1.024s        0m1.794s
user    0m0.348s        0m0.612s
sys     0m0.184s        0m0.264s

proc:
        With IDR API    With bitmap
real    0m0.059s        0m0.074s
user    0m0.000s        0m0.004s
sys     0m0.016s        0m0.016s

This patch (of 2):

Replace the current bitmap implementation for Process ID allocation.
Functions that are no longer required, for example, free_pidmap(),
alloc_pidmap(), etc.  are removed.  The rest of the functions are
modified to use the IDR API.  The change was made to make the PID
allocation less complex by replacing custom code with calls to generic
API.

[gs051095@gmail.com: v6]
  Link: http://lkml.kernel.org/r/1507760379-21662-2-git-send-email-gs051095@gmail.com
[avagin@openvz.org: restore the old behaviour of the ns_last_pid sysctl]
  Link: http://lkml.kernel.org/r/20171106183144.16368-1-avagin@openvz.org
Link: http://lkml.kernel.org/r/1507583624-22146-2-git-send-email-gs051095@gmail.com
Signed-off-by: Gargi Sharma <gs051095@gmail.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:03 -08:00
Ola N. Kaldestad
f9eb2fdd04 kernel/sysctl.c: code cleanups
Remove unnecessary else block, remove redundant return and call to kfree
in if block.

Link: http://lkml.kernel.org/r/1510238435-1655-1-git-send-email-mail@okal.no
Signed-off-by: Ola N. Kaldestad <mail@okal.no>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:03 -08:00
Dave Young
de40ccefd1 kdump: print a message in case parse_crashkernel_mem resulted in zero bytes
parse_crashkernel_mem() silently returns if we get zero bytes in the
parsing function.  It is useful for debugging to add a message,
especially if the kernel cannot boot correctly.

Add a pr_info instead of pr_warn because it is expected behavior for
size = 0, eg.  crashkernel=2G-4G:128M, size will be 0 in case system
memory is less than 2G.

Link: http://lkml.kernel.org/r/20171114080129.GA6115@dhcp-128-65.nay.redhat.com
Signed-off-by: Dave Young <dyoung@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Bhupesh Sharma <bhsharma@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:03 -08:00
Oleg Nesterov
426915796c kernel/signal.c: remove the no longer needed SIGNAL_UNKILLABLE check in complete_signal()
complete_signal() checks SIGNAL_UNKILLABLE before it starts to destroy
the thread group, today this is wrong in many ways.

If nothing else, fatal_signal_pending() should always imply that the
whole thread group (except ->group_exit_task if it is not NULL) is
killed, this check breaks the rule.

After the previous changes we can rely on sig_task_ignored();
sig_fatal(sig) && SIGNAL_UNKILLABLE can only be true if we actually want
to kill this task and sig == SIGKILL OR it is traced and debugger can
intercept the signal.

This should hopefully fix the problem reported by Dmitry.  This
test-case

	static int init(void *arg)
	{
		for (;;)
			pause();
	}

	int main(void)
	{
		char stack[16 * 1024];

		for (;;) {
			int pid = clone(init, stack + sizeof(stack)/2,
					CLONE_NEWPID | SIGCHLD, NULL);
			assert(pid > 0);

			assert(ptrace(PTRACE_ATTACH, pid, 0, 0) == 0);
			assert(waitpid(-1, NULL, WSTOPPED) == pid);

			assert(ptrace(PTRACE_DETACH, pid, 0, SIGSTOP) == 0);
			assert(syscall(__NR_tkill, pid, SIGKILL) == 0);
			assert(pid == wait(NULL));
		}
	}

triggers the WARN_ON_ONCE(!(task->jobctl & JOBCTL_STOP_PENDING)) in
task_participate_group_stop().  do_signal_stop()->signal_group_exit()
checks SIGNAL_GROUP_EXIT and return false, but task_set_jobctl_pending()
checks fatal_signal_pending() and does not set JOBCTL_STOP_PENDING.

And his should fix the minor security problem reported by Kyle,
SECCOMP_RET_TRACE can miss fatal_signal_pending() the same way if the
task is the root of a pid namespace.

Link: http://lkml.kernel.org/r/20171103184246.GD21036@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reported-by: Kyle Huey <me@kylehuey.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Kyle Huey <me@kylehuey.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:03 -08:00