Commit Graph

17836 Commits

Author SHA1 Message Date
Linus Torvalds
06eb4cc2e7 Merge branch 'for-3.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull more cgroup fixes from Tejun Heo:
 "Three more patches to fix cgroup_freezer breakage due to the recent
  cgroup internal locking changes - an operation cgroup_freezer was
  using now requires sleepable context and cgroup_freezer was invoking
  that while holding a spin lock.  cgroup_freezer was using an overly
  elaborate hierarchical locking scheme.

  While it's possible to convert the hierarchical spinlocks directly to
  mutexes, this patch simplifies the overall locking so that it uses a
  global mutex.  This has the added benefit of avoiding iterating
  potentially huge number of tasks under a spinlock.  While the patch is
  on the larger side in the devel cycle, the changes made are mostly
  straight-forward and the locking logic is a lot simpler afterwards"

* 'for-3.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: fix rcu_read_lock() leak in update_if_frozen()
  cgroup_freezer: replace freezer->lock with freezer_mutex
  cgroup: introduce task_css_is_root()
2014-05-21 18:36:40 +09:00
Linus Torvalds
95d08585e0 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 bug fix for a long standing issue:

   - Updating the expiry value of a relative timer _after_ letting the
     idle logic select a target cpu for the timer based on its stale
     expiry value is outright stupid.  Thanks to Viresh for spotting the
     brainfart"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hrtimer: Set expiry time before switch_hrtimer_base()
2014-05-20 14:19:10 +09:00
Tejun Heo
36e9d2ebcc cgroup: fix rcu_read_lock() leak in update_if_frozen()
While updating cgroup_freezer locking, 68fafb77d827 ("cgroup_freezer:
replace freezer->lock with freezer_mutex") introduced a bug in
update_if_frozen() where it returns with rcu_read_lock() held.  Fix it
by adding rcu_read_unlock() before returning.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
2014-05-13 11:28:30 -04:00
Tejun Heo
e5ced8ebb1 cgroup_freezer: replace freezer->lock with freezer_mutex
After 96d365e0b8 ("cgroup: make css_set_lock a rwsem and rename it
to css_set_rwsem"), css task iterators requires sleepable context as
it may block on css_set_rwsem.  I missed that cgroup_freezer was
iterating tasks under IRQ-safe spinlock freezer->lock.  This leads to
errors like the following on freezer state reads and transitions.

  BUG: sleeping function called from invalid context at /work
 /os/work/kernel/locking/rwsem.c:20
  in_atomic(): 0, irqs_disabled(): 0, pid: 462, name: bash
  5 locks held by bash/462:
   #0:  (sb_writers#7){.+.+.+}, at: [<ffffffff811f0843>] vfs_write+0x1a3/0x1c0
   #1:  (&of->mutex){+.+.+.}, at: [<ffffffff8126d78b>] kernfs_fop_write+0xbb/0x170
   #2:  (s_active#70){.+.+.+}, at: [<ffffffff8126d793>] kernfs_fop_write+0xc3/0x170
   #3:  (freezer_mutex){+.+...}, at: [<ffffffff81135981>] freezer_write+0x61/0x1e0
   #4:  (rcu_read_lock){......}, at: [<ffffffff81135973>] freezer_write+0x53/0x1e0
  Preemption disabled at:[<ffffffff81104404>] console_unlock+0x1e4/0x460

  CPU: 3 PID: 462 Comm: bash Not tainted 3.15.0-rc1-work+ #10
  Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
   ffff88000916a6d0 ffff88000e0a3da0 ffffffff81cf8c96 0000000000000000
   ffff88000e0a3dc8 ffffffff810cf4f2 ffffffff82388040 ffff880013aaf740
   0000000000000002 ffff88000e0a3de8 ffffffff81d05974 0000000000000246
  Call Trace:
   [<ffffffff81cf8c96>] dump_stack+0x4e/0x7a
   [<ffffffff810cf4f2>] __might_sleep+0x162/0x260
   [<ffffffff81d05974>] down_read+0x24/0x60
   [<ffffffff81133e87>] css_task_iter_start+0x27/0x70
   [<ffffffff8113584d>] freezer_apply_state+0x5d/0x130
   [<ffffffff81135a16>] freezer_write+0xf6/0x1e0
   [<ffffffff8112eb88>] cgroup_file_write+0xd8/0x230
   [<ffffffff8126d7b7>] kernfs_fop_write+0xe7/0x170
   [<ffffffff811f0756>] vfs_write+0xb6/0x1c0
   [<ffffffff811f121d>] SyS_write+0x4d/0xc0
   [<ffffffff81d08292>] system_call_fastpath+0x16/0x1b

freezer->lock used to be used in hot paths but that time is long gone
and there's no reason for the lock to be IRQ-safe spinlock or even
per-cgroup.  In fact, given the fact that a cgroup may contain large
number of tasks, it's not a good idea to iterate over them while
holding IRQ-safe spinlock.

Let's simplify locking by replacing per-cgroup freezer->lock with
global freezer_mutex.  This also makes the comments explaining the
intricacies of policy inheritance and the locking around it as the
states are protected by a common mutex.

The conversion is mostly straight-forward.  The followings are worth
mentioning.

* freezer_css_online() no longer needs double locking.

* freezer_attach() now performs propagation simply while holding
  freezer_mutex.  update_if_frozen() race no longer exists and the
  comment is removed.

* freezer_fork() now tests whether the task is in root cgroup using
  the new task_css_is_root() without doing rcu_read_lock/unlock().  If
  not, it grabs freezer_mutex and performs the operation.

* freezer_read() and freezer_change_state() grab freezer_mutex across
  the whole operation and pin the css while iterating so that each
  descendant processing happens in sleepable context.

Fixes: 96d365e0b8 ("cgroup: make css_set_lock a rwsem and rename it to css_set_rwsem")
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
2014-05-13 11:26:31 -04:00
Tejun Heo
5024ae29cd cgroup: introduce task_css_is_root()
Determining the css of a task usually requires RCU read lock as that's
the only thing which keeps the returned css accessible till its
reference is acquired; however, testing whether a task belongs to the
root can be performed without dereferencing the returned css by
comparing the returned pointer against the root one in init_css_set[]
which never changes.

Implement task_css_is_root() which can be invoked in any context.
This will be used by the scheduled cgroup_freezer change.

v2: cgroup no longer supports modular controllers.  No need to export
    init_css_set.  Pointed out by Li.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
2014-05-13 11:26:27 -04:00
Linus Torvalds
efb2b1d5fd Merge branch 'for-3.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue fixes from Tejun Heo:
 "Fixes for two bugs in workqueue.

  One is exiting with internal mutex held in a failure path of
  wq_update_unbound_numa().  The other is a subtle and unlikely
  use-after-possible-last-put in the rescuer logic.  Both have been
  around for quite some time now and are unlikely to have triggered
  noticeably often.  All patches are marked for -stable backport"

* 'for-3.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: fix a possible race condition between rescuer and pwq-release
  workqueue: make rescuer_thread() empty wq->maydays list before exiting
  workqueue: fix bugs in wq_update_unbound_numa() failure path
2014-05-13 11:24:07 +09:00
Linus Torvalds
26a41cd1ee Merge branch 'for-3.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:
 "During recent restructuring, device_cgroup unified config input check
  and enforcement logic; unfortunately, it turned out to share too much.
  Aristeu's patches fix the breakage and marked for -stable backport.

  The other two patches are fallouts from kernfs conversion.  The blkcg
  change is temporary and will go away once kernfs internal locking gets
  simplified (patches pending)"

* 'for-3.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  blkcg: use trylock on blkcg_pol_mutex in blkcg_reset_stats()
  device_cgroup: check if exception removal is allowed
  device_cgroup: fix the comment format for recently added functions
  device_cgroup: rework device access check and exception checking
  cgroup: fix the retry path of cgroup_mount()
2014-05-13 11:22:57 +09:00
Viresh Kumar
84ea7fe379 hrtimer: Set expiry time before switch_hrtimer_base()
switch_hrtimer_base() calls hrtimer_check_target() which ensures that
we do not migrate a timer to a remote cpu if the timer expires before
the current programmed expiry time on that remote cpu.

But __hrtimer_start_range_ns() calls switch_hrtimer_base() before the
new expiry time is set. So the sanity check in hrtimer_check_target()
is operating on stale or even uninitialized data.

Update expiry time before calling switch_hrtimer_base().

[ tglx: Rewrote changelog once again ]

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linaro-kernel@lists.linaro.org
Cc: linaro-networking@linaro.org
Cc: fweisbec@gmail.com
Cc: arvind.chauhan@arm.com
Link: http://lkml.kernel.org/r/81999e148745fc51bbcd0615823fbab9b2e87e23.1399882253.git.viresh.kumar@linaro.org
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-05-12 10:47:39 +02:00
Linus Torvalds
181da3c34a Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Peter Anvin:
 "A somewhat unpleasantly large collection of small fixes.  The big ones
  are the __visible tree sweep and a fix for 'earlyprintk=efi,keep'.  It
  was using __init functions with predictably suboptimal results.

  Another key fix is a build fix which would produce output that simply
  would not decompress correctly in some configuration, due to the
  existing Makefiles picking up an unfortunate local label and mistaking
  it for the global symbol _end.

  Additional fixes include the handling of 64-bit numbers when setting
  the vdso data page (a latent bug which became manifest when i386
  started exporting a vdso with time functions), a fix to the new MSR
  manipulation accessors which would cause features to not get properly
  unblocked, a build fix for 32-bit userland, and a few new platform
  quirks"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, vdso, time: Cast tv_nsec to u64 for proper shifting in update_vsyscall()
  x86: Fix typo in MSR_IA32_MISC_ENABLE_LIMIT_CPUID macro
  x86: Fix typo preventing msr_set/clear_bit from having an effect
  x86/intel: Add quirk to disable HPET for the Baytrail platform
  x86/hpet: Make boot_hpet_disable extern
  x86-64, build: Fix stack protector Makefile breakage with 32-bit userland
  x86/reboot: Add reboot quirk for Certec BPC600
  asmlinkage: Add explicit __visible to drivers/*, lib/*, kernel/*
  asmlinkage, x86: Add explicit __visible to arch/x86/*
  asmlinkage: Revert "lto: Make asmlinkage __visible"
  x86, build: Don't get confused by local symbols
  x86/efi: earlyprintk=efi,keep fix
2014-05-09 12:24:20 -07:00
Linus Torvalds
f322e26238 This contains two fixes.
The first is a long standing bug that causes bogus data to show up
 in the refcnt field of the module_refcnt tracepoint. It was
 introduced by a merge conflict resolution back in 2.6.35-rc days.
 
 The result should be refcnt = incs - decs, but instead it did
 refcnt = incs + decs.
 
 The second fix is to a bug that was introduced in this merge window
 that allowed for a tracepoint funcs pointer to be used after it
 was freed. Moving the location of where the probes are released
 solved the problem.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQEcBAABAgAGBQJTa/GQAAoJEKQekfcNnQGuGGUIAJCkrDZdnliE6f6Ur8aXJoX7
 gjkXRMmCjLM/X8yQc1H8YwDbSgaTQNmeyQvBbBZ1hUQBaMf5ft4KuFYMGvQRk3jp
 ZheQVumSzsQfO+yp5dRmzJ6H2G0BCInxq9VZyufZkCPUGsMyiIc+7+SGHEfjMgmW
 9XFWyfSr09thVlGanr+OTLXfwFm7GMD9nohLKXh9dhi/tO/gHq6lI83HK42Y1bWG
 4fZWJjO5GgCVbW4RanB6yr9RIe8NESKl37JYsAZX61iAvT8/mqIYGWx0i/DEGN5Q
 ap3WW5QPALLUlvUVgI9Um0KOrotbmKtnRwPeHYDmSQODwuKj5veiLXxL9XdHPLU=
 =lt0T
 -----END PGP SIGNATURE-----

Merge tag 'trace-fixes-v3.15-rc4-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "This contains two fixes.

  The first is a long standing bug that causes bogus data to show up in
  the refcnt field of the module_refcnt tracepoint.  It was introduced
  by a merge conflict resolution back in 2.6.35-rc days.

  The result should be 'refcnt = incs - decs', but instead it did
  'refcnt = incs + decs'.

  The second fix is to a bug that was introduced in this merge window
  that allowed for a tracepoint funcs pointer to be used after it was
  freed.  Moving the location of where the probes are released solved
  the problem"

* tag 'trace-fixes-v3.15-rc4-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracepoint: Fix use of tracepoint funcs after rcu free
  trace: module: Maintain a valid user count
2014-05-08 14:17:13 -07:00
Mathieu Desnoyers
8058bd0faa tracepoint: Fix use of tracepoint funcs after rcu free
Commit de7b297390 "tracepoint: Use struct pointer instead of name hash
for reg/unreg tracepoints" introduces a use after free by calling
release_probes on the old struct tracepoint array before the newly
allocated array is published with rcu_assign_pointer. There is a race
window where tracepoints (RCU readers) can perform a
"use-after-grace-period-after-free", which shows up as a GPF in
stress-tests.

Link: http://lkml.kernel.org/r/53698021.5020108@oracle.com
Link: http://lkml.kernel.org/p/1399549669-25465-1-git-send-email-mathieu.desnoyers@efficios.com

Reported-by: Sasha Levin <sasha.levin@oracle.com>
CC: Oleg Nesterov <oleg@redhat.com>
CC: Dave Jones <davej@redhat.com>
Fixes: de7b297390 "tracepoint: Use struct pointer instead of name hash for reg/unreg tracepoints"
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-05-08 09:10:56 -04:00
Andi Kleen
722a9f9299 asmlinkage: Add explicit __visible to drivers/*, lib/*, kernel/*
As requested by Linus add explicit __visible to the asmlinkage users.
This marks functions visible to assembler.

Tree sweep for rest of tree.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1398984278-29319-4-git-send-email-andi@firstfloor.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-05-05 16:07:46 -07:00
Linus Torvalds
2080cee435 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) e1000e computes header length incorrectly wrt vlans, fix from Vlad
    Yasevich.

 2) ns_capable() check in sock_diag netlink code, from Andrew
    Lutomirski.

 3) Fix invalid queue pairs handling in virtio_net, from Amos Kong.

 4) Checksum offloading busted in sxgbe driver due to incorrect
    descriptor layout, fix from Byungho An.

 5) Fix build failure with SMC_DEBUG set to 2 or larger, from Zi Shen
    Lim.

 6) Fix uninitialized A and X registers in BPF interpreter, from Alexei
    Starovoitov.

 7) Fix arch dependencies of candence driver.

 8) Fix netlink capabilities checking tree-wide, from Eric W Biederman.

 9) Don't dump IFLA_VF_PORTS if netlink request didn't ask for it in
    IFLA_EXT_MASK, from David Gibson.

10) IPV6 FIB dump restart doesn't handle table changes that happen
    meanwhile, causing the code to loop forever or emit dups, fix from
    Kumar Sandararajan.

11) Memory leak on VF removal in bnx2x, from Yuval Mintz.

12) Bug fixes for new Altera TSE driver from Vince Bridgers.

13) Fix route lookup key in SCTP, from Xugeng Zhang.

14) Use BH blocking spinlocks in SLIP, as per a similar fix to CAN/SLCAN
    driver.  From Oliver Hartkopp.

15) TCP doesn't bump retransmit counters in some code paths, fix from
    Eric Dumazet.

16) Clamp delayed_ack in tcp_cubic to prevent theoretical divides by
    zero.  Fix from Liu Yu.

17) Fix locking imbalance in error paths of HHF packet scheduler, from
    John Fastabend.

18) Properly reference the transport module when vsock_core_init() runs,
    from Andy King.

19) Fix buffer overflow in cdc_ncm driver, from Bjørn Mork.

20) IP_ECN_decapsulate() doesn't see a correct SKB network header in
    ip_tunnel_rcv(), fix from Ying Cai.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (132 commits)
  net: macb: Fix race between HW and driver
  net: macb: Remove 'unlikely' optimization
  net: macb: Re-enable RX interrupt only when RX is done
  net: macb: Clear interrupt flags
  net: macb: Pass same size to DMA_UNMAP as used for DMA_MAP
  ip_tunnel: Set network header properly for IP_ECN_decapsulate()
  e1000e: Restrict MDIO Slow Mode workaround to relevant parts
  e1000e: Fix issue with link flap on 82579
  e1000e: Expand workaround for 10Mb HD throughput bug
  e1000e: Workaround for dropped packets in Gig/100 speeds on 82579
  net/mlx4_core: Don't issue PCIe speed/width checks for VFs
  net/mlx4_core: Load the Eth driver first
  net/mlx4_core: Fix slave id computation for single port VF
  net/mlx4_core: Adjust port number in qp_attach wrapper when detaching
  net: cdc_ncm: fix buffer overflow
  Altera TSE: ALTERA_TSE should depend on HAS_DMA
  vsock: Make transport the proto owner
  net: sched: lock imbalance in hhf qdisc
  net: mvmdio: Check for a valid interrupt instead of an error
  net phy: Check for aneg completion before setting state to PHY_RUNNING
  ...
2014-05-05 15:59:46 -07:00
Linus Torvalds
0384dcae2b Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:
 "This udpate delivers:

   - A fix for dynamic interrupt allocation on x86 which is required to
     exclude the GSI interrupts from the dynamic allocatable range.

     This was detected with the newfangled tablet SoCs which have GPIOs
     and therefor allocate a range of interrupts.  The MSI allocations
     already excluded the GSI range, so we never noticed before.

   - The last missing set_irq_affinity() repair, which was delayed due
     to testing issues

   - A few bug fixes for the armada SoC interrupt controller

   - A memory allocation fix for the TI crossbar interrupt controller

   - A trivial kernel-doc warning fix"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip: irq-crossbar: Not allocating enough memory
  irqchip: armanda: Sanitize set_irq_affinity()
  genirq: x86: Ensure that dynamic irq allocation does not conflict
  linux/interrupt.h: fix new kernel-doc warnings
  irqchip: armada-370-xp: Fix releasing of MSIs
  irqchip: armada-370-xp: implement the ->check_device() msi_chip operation
  irqchip: armada-370-xp: fix invalid cast of signed value into unsigned variable
2014-05-03 08:32:48 -07:00
Linus Torvalds
98facf0e1e Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
 "This update brings along:

   - Two fixes for long standing bugs in the hrtimer code, one which
     prevents remote enqueuing and the other preventing arbitrary delays
     after a interrupt hang was detected

   - A fix in the timer wheel which prevents math overflow

   - A fix for a long standing issue with the architected ARM timer
     related to the C3STOP mechanism.

   - A trivial compile fix for nspire SoC clocksource"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timer: Prevent overflow in apply_slack
  hrtimer: Prevent remote enqueue of leftmost timers
  hrtimer: Prevent all reprogramming if hang detected
  clocksource: nspire: Fix compiler warning
  clocksource: arch_arm_timer: Fix age-old arch timer C3STOP detection issue
2014-05-03 08:31:45 -07:00
Linus Torvalds
00622e61ed This is a small fix where the trigger code used the wrong
rcu_dereference(). It required rcu_dereference_sched() instead of
 the normal rcu_dereference(). It produces a nasty RCU lockdep splat
 due to the incorrect rcu notation.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQEcBAABAgAGBQJTZF+rAAoJEKQekfcNnQGufrIH/1Wa1hzNoq8n1JmejythN6Yn
 lQ9RvD0NFrKcO3wd8XyYUoRQXNZ0RJ6JJzERyNygVWp8zLF9TifywaFCZpyNEH91
 58qidUdAEBaOMHB6WAVVg056kSC7QG5+kRzgFKktQNDac29Ykw2hJBrFoAAlkoi2
 7slBOpnRnpgGn6cRU7hjCbaZs/RvVOJ9J00JeOWFFcM8vFcKMNZBypnwSpRCwc51
 ZU8O4UhewqwXuTL35Lrnoaf6LZltkaudbRsc4/xgidT+S6djXU+6vnboerdBajh9
 aWCNcI8WVV6UXkJ7X/Ft7i7gV181iCvU+vUVk9REXatEgH1RBTJlMhwgqH4fiLM=
 =vEMu
 -----END PGP SIGNATURE-----

Merge tag 'trace-fixes-v3.15-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "This is a small fix where the trigger code used the wrong
  rcu_dereference().  It required rcu_dereference_sched() instead of the
  normal rcu_dereference().  It produces a nasty RCU lockdep splat due
  to the incorrect rcu notation"

Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

* tag 'trace-fixes-v3.15-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Use rcu_dereference_sched() for trace event triggers
2014-05-03 08:30:44 -07:00
Steven Rostedt (Red Hat)
561a4fe851 tracing: Use rcu_dereference_sched() for trace event triggers
As trace event triggers are now part of the mainline kernel, I added
my trace event trigger tests to my test suite I run on all my kernels.
Now these tests get run under different config options, and one of
those options is CONFIG_PROVE_RCU, which checks under lockdep that
the rcu locking primitives are being used correctly. This triggered
the following splat:

===============================
[ INFO: suspicious RCU usage. ]
3.15.0-rc2-test+ #11 Not tainted
-------------------------------
kernel/trace/trace_events_trigger.c:80 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

rcu_scheduler_active = 1, debug_locks = 0
4 locks held by swapper/1/0:
 #0:  ((&(&j_cdbs->work)->timer)){..-...}, at: [<ffffffff8104d2cc>] call_timer_fn+0x5/0x1be
 #1:  (&(&pool->lock)->rlock){-.-...}, at: [<ffffffff81059856>] __queue_work+0x140/0x283
 #2:  (&p->pi_lock){-.-.-.}, at: [<ffffffff8106e961>] try_to_wake_up+0x2e/0x1e8
 #3:  (&rq->lock){-.-.-.}, at: [<ffffffff8106ead3>] try_to_wake_up+0x1a0/0x1e8

stack backtrace:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 3.15.0-rc2-test+ #11
Hardware name:                  /DG965MQ, BIOS MQ96510J.86A.0372.2006.0605.1717 06/05/2006
 0000000000000001 ffff88007e083b98 ffffffff819f53a5 0000000000000006
 ffff88007b0942c0 ffff88007e083bc8 ffffffff81081307 ffff88007ad96d20
 0000000000000000 ffff88007af2d840 ffff88007b2e701c ffff88007e083c18
Call Trace:
 <IRQ>  [<ffffffff819f53a5>] dump_stack+0x4f/0x7c
 [<ffffffff81081307>] lockdep_rcu_suspicious+0x107/0x110
 [<ffffffff810ee51c>] event_triggers_call+0x99/0x108
 [<ffffffff810e8174>] ftrace_event_buffer_commit+0x42/0xa4
 [<ffffffff8106aadc>] ftrace_raw_event_sched_wakeup_template+0x71/0x7c
 [<ffffffff8106bcbf>] ttwu_do_wakeup+0x7f/0xff
 [<ffffffff8106bd9b>] ttwu_do_activate.constprop.126+0x5c/0x61
 [<ffffffff8106eadf>] try_to_wake_up+0x1ac/0x1e8
 [<ffffffff8106eb77>] wake_up_process+0x36/0x3b
 [<ffffffff810575cc>] wake_up_worker+0x24/0x26
 [<ffffffff810578bc>] insert_work+0x5c/0x65
 [<ffffffff81059982>] __queue_work+0x26c/0x283
 [<ffffffff81059999>] ? __queue_work+0x283/0x283
 [<ffffffff810599b7>] delayed_work_timer_fn+0x1e/0x20
 [<ffffffff8104d3a6>] call_timer_fn+0xdf/0x1be^M
 [<ffffffff8104d2cc>] ? call_timer_fn+0x5/0x1be
 [<ffffffff81059999>] ? __queue_work+0x283/0x283
 [<ffffffff8104d823>] run_timer_softirq+0x1a4/0x22f^M
 [<ffffffff8104696d>] __do_softirq+0x17b/0x31b^M
 [<ffffffff81046d03>] irq_exit+0x42/0x97
 [<ffffffff81a08db6>] smp_apic_timer_interrupt+0x37/0x44
 [<ffffffff81a07a2f>] apic_timer_interrupt+0x6f/0x80
 <EOI>  [<ffffffff8100a5d8>] ? default_idle+0x21/0x32
 [<ffffffff8100a5d6>] ? default_idle+0x1f/0x32
 [<ffffffff8100ac10>] arch_cpu_idle+0xf/0x11
 [<ffffffff8107b3a4>] cpu_startup_entry+0x1a3/0x213
 [<ffffffff8102a23c>] start_secondary+0x212/0x219

The cause is that the triggers are protected by rcu_read_lock_sched() but
the data is dereferenced with rcu_dereference() which expects it to
be protected with rcu_read_lock(). The proper reference should be
rcu_dereference_sched().

Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: stable@vger.kernel.org # 3.14+
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-05-02 23:12:42 -04:00
Linus Torvalds
60b88f3941 Fixed one missing place for the new taint flag, and remove a warning
giving only false positives (now we finally figured out why).
 
 Cheers,
 Rusty.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJTYdCQAAoJENkgDmzRrbjxms4QALIGN2l8VugSoh3TSRHSGZtj
 5clH84FXkDR8DFA0w9rYxAsr1EhTadet8U1nCm6LWaz8FAPizH2hyUq6tFMU1+Jk
 zdWRPYLhuUBWW+XVFSeYo2gIclFHEYefawX9SmRcZJxuDy7xHW/bkmX/NT5p/Ll7
 3eKRPckO09agofLQgIOJGL21IQPFXYiCwur5b/OvNfzEkBfRmUALbO2oFhU+oebZ
 2P4M3Wmp7gEGbus2dB23v06BqpEhrdpXlAnvM61PS8exhsQI6ojgL3ZAYEl+6wkr
 whd0SjYs5Sd+3czlQDhlArYlcOlVAhvY4F5CHysEmM/CxjF1YAnk2Q7RLOV958Bk
 TTfDGG2b8qkJwN/2+CymDXyIUIppNPMuPXSOp3XQrRGOz8Uyh1URQD8l24Ssmrtt
 +3fUPDZ6npmtkxZdBu0SkdesCXYOtOeqpqt7MQpJiYbVMxx+ul4LnPB/A1+wf/Xx
 uvXMrpp1fz/hs9ZOK8n+nRMtbsc75LDQ0lYGcbbW8YJRkluf5/GJgyG8ptIvbbFW
 kh90ObVaJ2FN0Uj31POdtsOwM7tf2W5C1lZkE/aWf+wgNylHAylYoUHRIGFOcCqV
 PeWrD0Chz+bzrZk1sT6cHIvTu6u5ShjkOfcEGhWK2JFllxpKO4eZV4O1IaGhWaoV
 Y9JtmJNSOnnS261i1Rmb
 =725P
 -----END PGP SIGNATURE-----

Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module fixes from Rusty Russell:
 "Fixed one missing place for the new taint flag, and remove a warning
  giving only false positives (now we finally figured out why)"

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  module: remove warning about waiting module removal.
  Fix: tracing: use 'E' instead of 'X' for unsigned module taint flag
2014-05-01 10:35:01 -07:00
Jiri Bohac
98a01e779f timer: Prevent overflow in apply_slack
On architectures with sizeof(int) < sizeof (long), the
computation of mask inside apply_slack() can be undefined if the
computed bit is > 32.

E.g. with: expires = 0xffffe6f5 and slack = 25, we get:

expires_limit = 0x20000000e
bit = 33
mask = (1 << 33) - 1  /* undefined */

On x86, mask becomes 1 and and the slack is not applied properly.
On s390, mask is -1, expires is set to 0 and the timer fires immediately.

Use 1UL << bit to solve that issue.

Suggested-by: Deborah Townsend <dstownse@us.ibm.com>
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20140418152310.GA13654@midget.suse.cz
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-04-30 13:46:17 +02:00
Leon Ma
012a45e3f4 hrtimer: Prevent remote enqueue of leftmost timers
If a cpu is idle and starts an hrtimer which is not pinned on that
same cpu, the nohz code might target the timer to a different cpu.

In the case that we switch the cpu base of the timer we already have a
sanity check in place, which determines whether the timer is earlier
than the current leftmost timer on the target cpu. In that case we
enqueue the timer on the current cpu because we cannot reprogram the
clock event device on the target.

If the timers base is already the target CPU we do not have this
sanity check in place so we enqueue the timer as the leftmost timer in
the target cpus rb tree, but we cannot reprogram the clock event
device on the target cpu. So the timer expires late and subsequently
prevents the reprogramming of the target cpu clock event device until
the previously programmed event fires or a timer with an earlier
expiry time gets enqueued on the target cpu itself.

Add the same target check as we have for the switch base case and
start the timer on the current cpu if it would become the leftmost
timer on the target.

[ tglx: Rewrote subject and changelog ]

Signed-off-by: Leon Ma <xindong.ma@intel.com>
Link: http://lkml.kernel.org/r/1398847391-5994-1-git-send-email-xindong.ma@intel.com
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-04-30 12:34:51 +02:00
Stuart Hayes
6c6c0d5a1c hrtimer: Prevent all reprogramming if hang detected
If the last hrtimer interrupt detected a hang it sets hang_detected=1
and programs the clock event device with a delay to let the system
make progress.

If hang_detected == 1, we prevent reprogramming of the clock event
device in hrtimer_reprogram() but not in hrtimer_force_reprogram().

This can lead to the following situation:

hrtimer_interrupt()
   hang_detected = 1;
   program ce device to Xms from now (hang delay)

We have two timers pending:
   T1 expires 50ms from now
   T2 expires 5s from now

Now T1 gets canceled, which causes hrtimer_force_reprogram() to be
invoked, which in turn programs the clock event device to T2 (5
seconds from now).

Any hrtimer_start after that will not reprogram the hardware due to
hang_detected still being set. So we effectivly block all timers until
the T2 event fires and cleans up the hang situation.

Add a check for hang_detected to hrtimer_force_reprogram() which
prevents the reprogramming of the hang delay in the hardware
timer. The subsequent hrtimer_interrupt will resolve all outstanding
issues.

[ tglx: Rewrote subject and changelog and fixed up the comment in
  	hrtimer_force_reprogram() ]

Signed-off-by: Stuart Hayes <stuart.w.hayes@gmail.com>
Link: http://lkml.kernel.org/r/53602DC6.2060101@gmail.com
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-04-30 12:34:51 +02:00
Linus Torvalds
2aafe1a4d4 Takao Indoh reported that he was able to cause a ftrace bug while
loading a module and enabling function tracing at the same time.
 
 He uncovered a race where the module when loaded will convert the
 calls to mcount into nops, and expects the module's text to be RW.
 But when function tracing is enabled, it will convert all kernel
 text (core and module) from RO to RW to convert the nops to calls
 to ftrace to record the function. After the convertion, it will
 convert all the text back from RW to RO.
 
 The issue is, it will also convert the module's text that is loading.
 If it converts it to RO before ftrace does its conversion, it will
 cause ftrace to fail and require a reboot to fix it again.
 
 This patch moves the ftrace module update that converts calls to mcount
 into nops to be done when the module state is still MODULE_STATE_UNFORMED.
 This will ignore the module when the text is being converted from
 RW back to RO.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQEcBAABAgAGBQJTXuHsAAoJEKQekfcNnQGuT7cIAJQhwX2fpdFr5eHwx0CyFo5c
 75V0xcRhJsGeXqfgekkRhCHYEfL7v4sl6D+Bj8qzLG/0QresF9jVSMUTTZqYFpFc
 t7f3oDDtdCmfofD/uyS7YOQ3JhU5ijo+Drzq8qRYtWNJJ0WCqbddpevcUiW1Zbvr
 LAT3lcb+2I5Y1Jnyfd920+0plAnoeOw1/BPuRVJINwh8zeyvWnmp3iq9fOPdhMQQ
 VhCCg+C2ILBPrCPFdwC5pVrL4a/CjyNd+LqtFXjLS9sO8s5KyUGkqKkbHMlhZeot
 uRWlZUSNZsh/jpP4X2b+dtYGQ4Rrnp253a594Kmrzm/MPdsAV62oDqOfN0tzm7w=
 =K59a
 -----END PGP SIGNATURE-----

Merge tag 'trace-fixes-v3.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull ftrace bugfix from Steven Rostedt:
 "Takao Indoh reported that he was able to cause a ftrace bug while
  loading a module and enabling function tracing at the same time.

  He uncovered a race where the module when loaded will convert the
  calls to mcount into nops, and expects the module's text to be RW.
  But when function tracing is enabled, it will convert all kernel text
  (core and module) from RO to RW to convert the nops to calls to ftrace
  to record the function.  After the convertion, it will convert all the
  text back from RW to RO.

  The issue is, it will also convert the module's text that is loading.
  If it converts it to RO before ftrace does its conversion, it will
  cause ftrace to fail and require a reboot to fix it again.

  This patch moves the ftrace module update that converts calls to
  mcount into nops to be done when the module state is still
  MODULE_STATE_UNFORMED.  This will ignore the module when the text is
  being converted from RW back to RO"

* tag 'trace-fixes-v3.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace/module: Hardcode ftrace_module_init() call into load_module()
2014-04-28 16:57:51 -07:00
Steven Rostedt (Red Hat)
a949ae560a ftrace/module: Hardcode ftrace_module_init() call into load_module()
A race exists between module loading and enabling of function tracer.

	CPU 1				CPU 2
	-----				-----
  load_module()
   module->state = MODULE_STATE_COMING

				register_ftrace_function()
				 mutex_lock(&ftrace_lock);
				 ftrace_startup()
				  update_ftrace_function();
				   ftrace_arch_code_modify_prepare()
				    set_all_module_text_rw();
				   <enables-ftrace>
				    ftrace_arch_code_modify_post_process()
				     set_all_module_text_ro();

				[ here all module text is set to RO,
				  including the module that is
				  loading!! ]

   blocking_notifier_call_chain(MODULE_STATE_COMING);
    ftrace_init_module()

     [ tries to modify code, but it's RO, and fails!
       ftrace_bug() is called]

When this race happens, ftrace_bug() will produces a nasty warning and
all of the function tracing features will be disabled until reboot.

The simple solution is to treate module load the same way the core
kernel is treated at boot. To hardcode the ftrace function modification
of converting calls to mcount into nops. This is done in init/main.c
there's no reason it could not be done in load_module(). This gives
a better control of the changes and doesn't tie the state of the
module to its notifiers as much. Ftrace is special, it needs to be
treated as such.

The reason this would work, is that the ftrace_module_init() would be
called while the module is in MODULE_STATE_UNFORMED, which is ignored
by the set_all_module_text_ro() call.

Link: http://lkml.kernel.org/r/1395637826-3312-1-git-send-email-indou.takao@jp.fujitsu.com

Reported-by: Takao Indoh <indou.takao@jp.fujitsu.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: stable@vger.kernel.org # 2.6.38+
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-04-28 10:37:21 -04:00
Thomas Gleixner
62a08ae2a5 genirq: x86: Ensure that dynamic irq allocation does not conflict
On x86 the allocation of irq descriptors may allocate interrupts which
are in the range of the GSI interrupts. That's wrong as those
interrupts are hardwired and we don't have the irq domain translation
like PPC. So one of these interrupts can be hooked up later to one of
the devices which are hard wired to it and the io_apic init code for
that particular interrupt line happily reuses that descriptor with a
completely different configuration so hell breaks lose.

Inside x86 we allocate dynamic interrupts from above nr_gsi_irqs,
except for a few usage sites which have not yet blown up in our face
for whatever reason. But for drivers which need an irq range, like the
GPIO drivers, we have no limit in place and we don't want to expose
such a detail to a driver.

To cure this introduce a function which an architecture can implement
to impose a lower bound on the dynamic interrupt allocations.

Implement it for x86 and set the lower bound to nr_gsi_irqs, which is
the end of the hardwired interrupt space, so all dynamic allocations
happen above.

That not only allows the GPIO driver to work sanely, it also protects
the bogus callsites of create_irq_nr() in hpet, uv, irq_remapping and
htirq code. They need to be cleaned up as well, but that's a separate
issue.

Reported-by: Jin Yao <yao.jin@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Mathias Nyman <mathias.nyman@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Krogerus Heikki <heikki.krogerus@intel.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1404241617360.28206@ionos.tec.linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-04-28 12:20:00 +02:00
Rusty Russell
79465d2fd4 module: remove warning about waiting module removal.
We remove the waiting module removal in commit 3f2b9c9cdf (September
2013), but it turns out that modprobe in kmod (< version 16) was
asking for waiting module removal.  No one noticed since modprobe would
check for 0 usage immediately before trying to remove the module, and
the race is unlikely.

However, it means that anyone running old (but not ancient) kmod
versions is hitting the printk designed to see if anyone was running
"rmmod -w".  All reports so far have been false positives, so remove
the warning.

Fixes: 3f2b9c9cdf
Reported-by: Valerio Vanni <valerio.vanni@inwind.it>
Cc: Elliott, Robert (Server Storage) <Elliott@hp.com>
Cc: stable@kernel.org
Acked-by: Lucas De Marchi <lucas.de.marchi@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-04-28 11:06:59 +09:30
Linus Torvalds
d9e9e8e2fe 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 slighlty large fix for a subtle issue in the CPU hotplug code of
  certain ARM SoCs, where the not yet online cpu needs to setup the cpu
  local timer and needs to set the interrupt affinity to itself.
  Setting interrupt affinity to a not online cpu is prohibited and
  therefor the timer interrupt ends up on the wrong cpu, which leads to
  nasty complications.

  The SoC folks tried to hack around that in the SoC code in some more
  than nasty ways.  The proper solution is to have a way to enforce the
  affinity setting to a not online cpu.  The core patch to the genirq
  code provides that facility and the follow up patches make use of it
  in the GIC interrupt controller and the exynos timer driver.

  The change to the core code has no implications to existing users,
  except for the rename of the locked function and therefor the
  necessary fixup in mips/cavium.  Aside of that, no runtime impact is
  possible, as none of the existing interrupt chips implements anything
  which depends on the force argument of the irq_set_affinity()
  callback"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource: Exynos_mct: Register clock event after request_irq()
  clocksource: Exynos_mct: Use irq_force_affinity() in cpu bringup
  irqchip: Gic: Support forced affinity setting
  genirq: Allow forcing cpu affinity of interrupts
2014-04-27 11:21:03 -07:00
Eric W. Biederman
90f62cf30a net: Use netlink_ns_capable to verify the permisions of netlink messages
It is possible by passing a netlink socket to a more privileged
executable and then to fool that executable into writing to the socket
data that happens to be valid netlink message to do something that
privileged executable did not intend to do.

To keep this from happening replace bare capable and ns_capable calls
with netlink_capable, netlink_net_calls and netlink_ns_capable calls.
Which act the same as the previous calls except they verify that the
opener of the socket had the desired permissions as well.

Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-24 13:44:54 -04:00
Rafael J. Wysocki
f3f125324f PM / suspend: Make cpuidle work in the "freeze" state
The "freeze" system sleep state introduced by commit 7e73c5ae6e
(PM: Introduce suspend state PM_SUSPEND_FREEZE) requires cpuidle
to be functional when freeze_enter() is executed to work correctly
(that is, to be able to save any more energy than runtime idle),
but that is impossible after commit 8651f97bd9 (PM / cpuidle:
System resume hang fix with cpuidle) which caused cpuidle to be
paused in dpm_suspend_noirq() and resumed in dpm_resume_noirq().

To avoid that problem, add cpuidle_resume() and cpuidle_pause()
to the beginning and the end of freeze_enter(), respectively.

Reported-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
2014-04-21 23:39:59 +02:00
Linus Torvalds
8f98f6f5d6 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 SCHED_DEADLINE task selection fix
   - a sched/numa related lockdep splat fix"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Check for stop task appearance when balancing happens
  sched/numa: Fix task_numa_free() lockdep splat
2014-04-19 10:40:51 -07:00
Linus Torvalds
ebfc45ee70 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull more networking fixes from David Miller:

 1) Fix mlx4_en_netpoll implementation, it needs to schedule a NAPI
    context, not synchronize it.  From Chris Mason.

 2) Ipv4 flow input interface should never be zero, it should be
    LOOPBACK_IFINDEX instead.  From Cong Wang and Julian Anastasov.

 3) Properly configure MAC to PHY connection in mvneta devices, from
    Thomas Petazzoni.

 4) sys_recv should use SYSCALL_DEFINE.  From Jan Glauber.

 5) Tunnel driver ioctls do not use the correct namespace, fix from
    Nicolas Dichtel.

 6) Fix memory leak on seccomp filter attach, from Kees Cook.

 7) Fix lockdep warning for nested vlans, from Ding Tianhong.

 8) Crashes can happen in SCTP due to how the auth_enable value is
    managed, fix from Vlad Yasevich.

 9) Wireless fixes from John W Linville and co.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (45 commits)
  net: sctp: cache auth_enable per endpoint
  tg3: update rx_jumbo_pending ring param only when jumbo frames are enabled
  vlan: Fix lockdep warning when vlan dev handle notification
  seccomp: fix memory leak on filter attach
  isdn: icn: buffer overflow in icn_command()
  ip6_tunnel: use the right netns in ioctl handler
  sit: use the right netns in ioctl handler
  ip_tunnel: use the right netns in ioctl handler
  net: use SYSCALL_DEFINEx for sys_recv
  net: mdio-gpio: Add support for separate MDI and MDO gpio pins
  net: mdio-gpio: Add support for active low gpio pins
  net: mdio-gpio: Use devm_ functions where possible
  ipv4, route: pass 0 instead of LOOPBACK_IFINDEX to fib_validate_source()
  ipv4, fib: pass LOOPBACK_IFINDEX instead of 0 to flowi4_iif
  mlx4_en: don't use napi_synchronize inside mlx4_en_netpoll
  net: mvneta: properly configure the MAC <-> PHY connection in all situations
  net: phy: add minimal support for QSGMII PHY
  sfc:On MCDI timeout, issue an FLR (and mark MCDI to fail-fast)
  mwifiex: fix hung task on command timeout
  mwifiex: process event before command response
  ...
2014-04-18 17:53:46 -07:00
Andrew Morton
7861144b8c kernel/watchdog.c:touch_softlockup_watchdog(): use raw_cpu_write()
Fix:

  BUG: using __this_cpu_write() in preemptible [00000000] code: systemd-udevd/497
  caller is __this_cpu_preempt_check+0x13/0x20
  CPU: 3 PID: 497 Comm: systemd-udevd Tainted: G        W     3.15.0-rc1 #9
  Hardware name: Hewlett-Packard HP EliteBook 8470p/179B, BIOS 68ICF Ver. F.02 04/27/2012
  Call Trace:
    check_preemption_disabled+0xe1/0xf0
    __this_cpu_preempt_check+0x13/0x20
    touch_nmi_watchdog+0x28/0x40

Reported-by: Luis Henriques <luis.henriques@canonical.com>
Tested-by: Luis Henriques <luis.henriques@canonical.com>
Cc: Eric Piel <eric.piel@tremplin-utc.net>
Cc: Robert Moore <robert.moore@intel.com>
Cc: Lv Zheng <lv.zheng@intel.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-18 16:40:08 -07:00
Linus Torvalds
7d77879bfd This contains two fixes.
The first is to remove a duplication of creating debugfs files that
 already exist and causes an error report to be printed due to the
 failure of the second creation.
 
 The second is a memory leak fix that was introduced in 3.14.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQEcBAABAgAGBQJTUGZwAAoJEKQekfcNnQGu7W8IAIAMBVfrWdP6cmGle4tGfhVE
 sHcwqTH+07oANQJ3eFwFs5wBMb08s3hXwUHUxXcpjyq2Bs+AHr0vSL/nqCG4k8Ap
 2T4ntL7esC1BWKw2lVVVYD12FiL7grUXVlx/q0WE2NuhCzWzNRTyb8sKrPoCRUEB
 3o5rAt9+45PKUb2k/eqGBGhK8b4XDz2Wtk5Gj6YB3xttse/yjjcuw0gWMHN1JWfm
 eRuQUUBDDGUGkfF98k1aLrjPZooT3LIAV8L8md5C3ebEcXSC/h86hTYCGXv3oBDO
 8sxcT0zoQcLuFhjkYLL1J1lBW6gxaVh052jYmQwMppQMos+WID2un2E92Ccg49E=
 =BwLF
 -----END PGP SIGNATURE-----

Merge tag 'trace-fixes-v3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "This contains two fixes.

  The first is to remove a duplication of creating debugfs files that
  already exist and causes an error report to be printed due to the
  failure of the second creation.

  The second is a memory leak fix that was introduced in 3.14"

* tag 'trace-fixes-v3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing/uprobes: Fix uprobe_cpu_buffer memory leak
  tracing: Do not try to recreated toplevel set_ftrace_* files
2014-04-18 10:16:43 -07:00
Lai Jiangshan
77668c8b55 workqueue: fix a possible race condition between rescuer and pwq-release
There is a race condition between rescuer_thread() and
pwq_unbound_release_workfn().

Even after a pwq is scheduled for rescue, the associated work items
may be consumed by any worker.  If all of them are consumed before the
rescuer gets to them and the pwq's base ref was put due to attribute
change, the pwq may be released while still being linked on
@wq->maydays list making the rescuer dereference already freed pwq
later.

Make send_mayday() pin the target pwq until the rescuer is done with
it.

tj: Updated comment and patch description.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org # v3.10+
2014-04-18 12:33:29 -04:00
Lai Jiangshan
4d595b866d workqueue: make rescuer_thread() empty wq->maydays list before exiting
After a @pwq is scheduled for emergency execution, other workers may
consume the affectd work items before the rescuer gets to them.  This
means that a workqueue many have pwqs queued on @wq->maydays list
while not having any work item pending or in-flight.  If
destroy_workqueue() executes in such condition, the rescuer may exit
without emptying @wq->maydays.

This currently doesn't cause any actual harm.  destroy_workqueue() can
safely destroy all the involved data structures whether @wq->maydays
is populated or not as nobody access the list once the rescuer exits.

However, this is nasty and makes future development difficult.  Let's
update rescuer_thread() so that it empties @wq->maydays after seeing
should_stop to guarantee that the list is empty on rescuer exit.

tj: Updated comment and patch description.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org # v3.10+
2014-04-18 11:04:16 -04:00
Linus Torvalds
87a54cae0b Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
 "Viresh unearthed the following three hickups in the timer/timekeeping
  code:

   - Negated check for the result of a clock event selection

   - A missing early exit in the jiffies update path which causes
     update_wall_time to be called for nothing causing lock contention
     and wasted cycles in the timer interrupt

   - Checking a variable in the NOHZ code enable code for true which can
     only be set by that very code after the check succeeds.  That
     results in a rock solid runtime disablement of that feature"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tick-sched: Check tick_nohz_enabled in tick_nohz_switch_to_nohz()
  tick-sched: Don't call update_wall_time() when delta is lesser than tick_period
  tick-common: Fix wrong check in tick_check_replacement()
2014-04-17 16:19:10 -07:00
Thomas Gleixner
01f8fa4f01 genirq: Allow forcing cpu affinity of interrupts
The current implementation of irq_set_affinity() refuses rightfully to
route an interrupt to an offline cpu.

But there is a special case, where this is actually desired. Some of
the ARM SoCs have per cpu timers which require setting the affinity
during cpu startup where the cpu is not yet in the online mask.

If we can't do that, then the local timer interrupt for the about to
become online cpu is routed to some random online cpu.

The developers of the affected machines tried to work around that
issue, but that results in a massive mess in that timer code.

We have a yet unused argument in the set_affinity callbacks of the irq
chips, which I added back then for a similar reason. It was never
required so it got not used. But I'm happy that I never removed it.

That allows us to implement a sane handling of the above scenario. So
the affected SoC drivers can add the required force handling to their
interrupt chip, switch the timer code to irq_force_affinity() and
things just work.

This does not affect any existing user of irq_set_affinity().

Tagged for stable to allow a simple fix of the affected SoC clock
event drivers.

Reported-and-tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Tomasz Figa <t.figa@samsung.com>,
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>,
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: linux-arm-kernel@lists.infradead.org,
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20140416143315.717251504@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-04-17 23:36:27 +02:00
Li Zefan
e37a06f109 cgroup: fix the retry path of cgroup_mount()
If we hit the retry path, we'll call parse_cgroupfs_options() again,
but the string we pass to it has been modified by the previous call
to this function.

This bug can be observed by:

  # mount -t cgroup -o name=foo,cpuset xxx /mnt && umount /mnt && \
    mount -t cgroup -o name=foo,cpuset xxx /mnt
  mount: wrong fs type, bad option, bad superblock on xxx,
         missing codepage or helper program, or other error
  ...

The second mount passed "name=foo,cpuset" to the parser, and then it
hit the retry path and call the parser again, but this time the string
passed to the parser is "name=foo".

To fix this, we avoid calling parse_cgroupfs_options() again in this
case.

Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-04-17 11:18:06 -04:00
zhangwei(Jovi)
6ea6215fe3 tracing/uprobes: Fix uprobe_cpu_buffer memory leak
Forgot to free uprobe_cpu_buffer percpu page in uprobe_buffer_disable().

Link: http://lkml.kernel.org/p/534F8B3F.1090407@huawei.com

Cc: stable@vger.kernel.org # v3.14+
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-04-17 10:44:42 -04:00
Kirill Tkhai
a1d9a3231e sched: Check for stop task appearance when balancing happens
We need to do it like we do for the other higher priority classes..

Signed-off-by: Kirill Tkhai <tkhai@yandex.ru>
Cc: Michael wang <wangyun@linux.vnet.ibm.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/336561397137116@web27h.yandex.ru
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-17 13:39:51 +02:00
Linus Torvalds
d99d5917e7 Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Ingo Molnar:
 "liblockdep fixes and mutex debugging fixes"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/mutex: Fix debug_mutexes
  tools/liblockdep: Add proper versioning to the shared obj
  tools/liblockdep: Ignore asmlinkage and visible
2014-04-16 16:35:18 -07:00
Steven Rostedt (Red Hat)
5d6c97c559 tracing: Do not try to recreated toplevel set_ftrace_* files
With the restructing of the function tracer working with instances, the
"top level" buffer is a bit special, as the function tracing is mapped
to the same set of filters. This is done by using a "global_ops" descriptor
and having the "set_ftrace_filter" and "set_ftrace_notrace" map to it.

When an instance is created, it creates the same files but its for the
local instance and not the global_ops.

The issues is that the local instance creation shares some code with
the global instance one and we end up trying to create th top level
"set_ftrace_*" files twice, and on boot up, we get an error like this:

 Could not create debugfs 'set_ftrace_filter' entry
 Could not create debugfs 'set_ftrace_notrace' entry

The reason they failed to be created was because they were created
twice, and the second time gives this error as you can not create the
same file twice.

Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-04-16 19:21:53 -04:00
Kees Cook
0acf07d240 seccomp: fix memory leak on filter attach
This sets the correct error code when final filter memory is unavailable,
and frees the raw filter no matter what.

unreferenced object 0xffff8800d6ea4000 (size 512):
  comm "sshd", pid 278, jiffies 4294898315 (age 46.653s)
  hex dump (first 32 bytes):
    21 00 00 00 04 00 00 00 15 00 01 00 3e 00 00 c0  !...........>...
    06 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00  ........!.......
  backtrace:
    [<ffffffff8151414e>] kmemleak_alloc+0x4e/0xb0
    [<ffffffff811a3a40>] __kmalloc+0x280/0x320
    [<ffffffff8110842e>] prctl_set_seccomp+0x11e/0x3b0
    [<ffffffff8107bb6b>] SyS_prctl+0x3bb/0x4a0
    [<ffffffff8152ef2d>] system_call_fastpath+0x1a/0x1f
    [<ffffffffffffffff>] 0xffffffffffffffff

Reported-by: Masami Ichikawa <masami256@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Tested-by: Masami Ichikawa <masami256@gmail.com>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-16 15:25:53 -04:00
Daeseok Youn
77f300b198 workqueue: fix bugs in wq_update_unbound_numa() failure path
wq_update_unbound_numa() failure path has the following two bugs.

- alloc_unbound_pwq() is called without holding wq->mutex; however, if
  the allocation fails, it jumps to out_unlock which tries to unlock
  wq->mutex.

- The function should switch to dfl_pwq on failure but didn't do so
  after alloc_unbound_pwq() failure.

Fix it by regrabbing wq->mutex and jumping to use_dfl_pwq on
alloc_unbound_pwq() failure.

Signed-off-by: Daeseok Youn <daeseok.youn@gmail.com>
Acked-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org
Fixes: 4c16bd327c ("workqueue: implement NUMA affinity for unbound workqueues")
2014-04-16 13:27:57 -04:00
Linus Torvalds
10ec34fcb1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Fix BPF filter validation of netlink attribute accesses, from
    Mathias Kruase.

 2) Netfilter conntrack generation seqcount not initialized properly,
    from Andrey Vagin.

 3) Fix comparison mask computation on big-endian in nft_cmp_fast(),
    from Patrick McHardy.

 4) Properly limit MTU over ipv6, from Eric Dumazet.

 5) Fix seccomp system call argument population on 32-bit, from Daniel
    Borkmann.

 6) skb_network_protocol() should not use hard-coded ETH_HLEN, instead
    skb->mac_len needs to be used.  From Vlad Yasevich.

 7) We have several cases of using socket based communications to
    implement a tunnel.  For example, some tunnels are encapsulations
    over UDP so we use an internal kernel UDP socket to do the
    transmits.

    These tunnels should behave just like other software devices and
    pass the packets on down to the next layer.

    Most importantly we want the top-level socket (eg TCP) that created
    the traffic to be charged for the SKB memory.

    However, once you get into the IP output path, we have code that
    assumed that whatever was attached to skb->sk is an IP socket.

    To keep the top-level socket being charged for the SKB memory,
    whilst satisfying the needs of the IP output path, we now pass in an
    explicit 'sk' argument.

    From Eric Dumazet.

 8) ping_init_sock() leaks group info, from Xiaoming Wang.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (33 commits)
  cxgb4: use the correct max size for firmware flash
  qlcnic: Fix MSI-X initialization code
  ip6_gre: don't allow to remove the fb_tunnel_dev
  ipv4: add a sock pointer to dst->output() path.
  ipv4: add a sock pointer to ip_queue_xmit()
  driver/net: cosa driver uses udelay incorrectly
  at86rf230: fix __at86rf230_read_subreg function
  at86rf230: remove check if AVDD settled
  net: cadence: Add architecture dependencies
  net: Start with correct mac_len in skb_network_protocol
  Revert "net: sctp: Fix a_rwnd/rwnd management to reflect real state of the receiver's buffer"
  cxgb4: Save the correct mac addr for hw-loopback connections in the L2T
  net: filter: seccomp: fix wrong decoding of BPF_S_ANC_SECCOMP_LD_W
  seccomp: fix populating a0-a5 syscall args in 32-bit x86 BPF
  qlcnic: Do not disable SR-IOV when VFs are assigned to VMs
  qlcnic: Fix QLogic application/driver interface for virtual NIC configuration
  qlcnic: Fix PVID configuration on eSwitch port.
  qlcnic: Fix max ring count calculation
  qlcnic: Fix to send INIT_NIC_FUNC as first mailbox.
  qlcnic: Fix panic due to uninitialzed delayed_work struct in use.
  ...
2014-04-15 20:30:30 -07:00
Viresh Kumar
27630532ef tick-sched: Check tick_nohz_enabled in tick_nohz_switch_to_nohz()
Since commit d689fe222 (NOHZ: Check for nohz active instead of nohz
enabled) the tick_nohz_switch_to_nohz() function returns because it
checks for the tick_nohz_active flag. This can't be set, because the
function itself sets it.

Undo the change in tick_nohz_switch_to_nohz().

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linaro-kernel@lists.linaro.org
Cc: fweisbec@gmail.com
Cc: Arvind.Chauhan@arm.com
Cc: linaro-networking@linaro.org
Cc: <stable@vger.kernel.org> # 3.13+
Link: http://lkml.kernel.org/r/40939c05f2d65d781b92b20302b02243d0654224.1397537987.git.viresh.kumar@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-04-15 20:26:58 +02:00
Viresh Kumar
03e6bdc5c4 tick-sched: Don't call update_wall_time() when delta is lesser than tick_period
In tick_do_update_jiffies64() we are processing ticks only if delta is
greater than tick_period. This is what we are supposed to do here and
it broke a bit with this patch:

commit 47a1b796 (tick/timekeeping: Call update_wall_time outside the
jiffies lock)

With above patch, we might end up calling update_wall_time() even if
delta is found to be smaller that tick_period. Fix this by returning
when the delta is less than tick period.

[ tglx: Made it a 3 liner and massaged changelog ]

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linaro-kernel@lists.linaro.org
Cc: fweisbec@gmail.com
Cc: Arvind.Chauhan@arm.com
Cc: linaro-networking@linaro.org
Cc: John Stultz <john.stultz@linaro.org>
Cc: <stable@vger.kernel.org> # v3.14+
Link: http://lkml.kernel.org/r/80afb18a494b0bd9710975bcc4de134ae323c74f.1397537987.git.viresh.kumar@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-04-15 20:26:45 +02:00
Viresh Kumar
521c42990e tick-common: Fix wrong check in tick_check_replacement()
tick_check_replacement() returns if a replacement of clock_event_device is
possible or not. It does this as the first check:

	if (tick_check_percpu(curdev, newdev, smp_processor_id()))
		return false;

Thats wrong. tick_check_percpu() returns true when the device is
useable. Check for false instead.

[ tglx: Massaged changelog ]

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: <stable@vger.kernel.org> # v3.11+
Cc: linaro-kernel@lists.linaro.org
Cc: fweisbec@gmail.com
Cc: Arvind.Chauhan@arm.com
Cc: linaro-networking@linaro.org
Link: http://lkml.kernel.org/r/486a02efe0246635aaba786e24b42d316438bf3b.1397537987.git.viresh.kumar@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-04-15 20:26:44 +02:00
Mikulas Patocka
e79323bd87 user namespace: fix incorrect memory barriers
smp_read_barrier_depends() can be used if there is data dependency between
the readers - i.e. if the read operation after the barrier uses address
that was obtained from the read operation before the barrier.

In this file, there is only control dependency, no data dependecy, so the
use of smp_read_barrier_depends() is incorrect. The code could fail in the
following way:
* the cpu predicts that idx < entries is true and starts executing the
  body of the for loop
* the cpu fetches map->extent[0].first and map->extent[0].count
* the cpu fetches map->nr_extents
* the cpu verifies that idx < extents is true, so it commits the
  instructions in the body of the for loop

The problem is that in this scenario, the cpu read map->extent[0].first
and map->nr_extents in the wrong order. We need a full read memory barrier
to prevent it.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-14 16:03:02 -07:00
Daniel Borkmann
2eac764832 seccomp: fix populating a0-a5 syscall args in 32-bit x86 BPF
Linus reports that on 32-bit x86 Chromium throws the following seccomp
resp. audit log messages:

  audit: type=1326 audit(1397359304.356:28108): auid=500 uid=500
gid=500 ses=2 subj=unconfined_u:unconfined_r:chrome_sandbox_t:s0-s0:c0.c1023
pid=3677 comm="chrome" exe="/opt/google/chrome/chrome" sig=0
syscall=172 compat=0 ip=0xb2dd9852 code=0x30000

  audit: type=1326 audit(1397359304.356:28109): auid=500 uid=500
gid=500 ses=2 subj=unconfined_u:unconfined_r:chrome_sandbox_t:s0-s0:c0.c1023
pid=3677 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 syscall=5
compat=0 ip=0xb2dd9852 code=0x50000

These audit messages are being triggered via audit_seccomp() through
__secure_computing() in seccomp mode (BPF) filter with seccomp return
codes 0x30000 (== SECCOMP_RET_TRAP) and 0x50000 (== SECCOMP_RET_ERRNO)
during filter runtime. Moreover, Linus reports that x86_64 Chromium
seems fine.

The underlying issue that explains this is that the implementation of
populate_seccomp_data() is wrong. Our seccomp data structure sd that
is being shared with user ABI is:

  struct seccomp_data {
    int nr;
    __u32 arch;
    __u64 instruction_pointer;
    __u64 args[6];
  };

Therefore, a simple cast to 'unsigned long *' for storing the value of
the syscall argument via syscall_get_arguments() is just wrong as on
32-bit x86 (or any other 32bit arch), it would result in storing a0-a5
at wrong offsets in args[] member, and thus i) could leak stack memory
to user space and ii) tampers with the logic of seccomp BPF programs
that read out and check for syscall arguments:

  syscall_get_arguments(task, regs, 0, 1, (unsigned long *) &sd->args[0]);

Tested on 32-bit x86 with Google Chrome, unfortunately only via remote
test machine through slow ssh X forwarding, but it fixes the issue on
my side. So fix it up by storing args in type correct variables, gcc
is clever and optimizes the copy away in other cases, e.g. x86_64.

Fixes: bd4cf0ed33 ("net: filter: rework/optimize internal BPF interpreter's instruction set")
Reported-and-bisected-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-14 16:26:47 -04:00
Davidlohr Bueso
d7e8af1afe futex: update documentation for ordering guarantees
Commits 11d4616bd0 ("futex: revert back to the explicit waiter
counting code") and 69cd9eba38 ("futex: avoid race between requeue and
wake") changed some of the finer details of how we think about futexes.
One was a late fix and the other a consequence of overlooking the whole
requeuing logic.

The first change caused our documentation to be incorrect, and the
second made us aware that we need to explicitly add more details to it.

Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-12 17:57:51 -07:00