I noticed the new sched_{set,get}attr() calls didn't properly deal
with the SCHED_RESET_ON_FORK hack.
Instead of propagating the flags in high bits nonsense use the brand
spanking new attr::sched_flags field.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@gmail.com>
Cc: Dario Faggioli <raistlin@linux.it>
Link: http://lkml.kernel.org/r/20140115162242.GJ31570@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fengguang Wu reported the following build warning:
> kernel/sched/core.c:3067 __sched_setscheduler() warn: unsigned 'attr->sched_priority' is never less than zero.
Since it doesn't make sense for attr::sched_priority to be negative,
remove the check, since we already test for an upper limit any actual
negative values passed in through the old param::sched_priority field
will still be detected.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@gmail.com>
Cc: Dario Faggioli <raistlin@linux.it>
Fixes: d50dde5a10 ("sched: Add new scheduler syscalls to support an extended scheduling parameters ABI")
Link: http://lkml.kernel.org/n/tip-fid9nalzii2r5voxtf4eh5kz@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Wu reported LTP failures:
> ltp.sched_setparam02.1.TFAIL
> ltp.sched_setparam02.2.TFAIL
> ltp.sched_setparam02.3.TFAIL
> ltp.sched_setparam03.1.TFAIL
There were 2 things wrong; firstly __setscheduler() failed on
sched_setparam()'s policy = -1, fix that by reading from p->policy in
that case.
Secondly, getparam() (and getattr()) would still report !0
sched_priority for !FIFO/RR tasks after having been such. So
unconditionally set p->rt_priority.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@gmail.com>
Cc: Dario Faggioli <raistlin@linux.it>
Fixes: d50dde5a10 ("sched: Add new scheduler syscalls to support an extended scheduling parameters ABI")
Link: http://lkml.kernel.org/r/20140115153320.GH31570@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Previously sched_setscheduler() and sched_setparam() would not affect
the nice value of a task, restore this behaviour.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: raistlin@linux.it
Cc: juri.lelli@gmail.com
Cc: Michael wang <wangyun@linux.vnet.ibm.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Fixes: d50dde5a10 ("sched: Add new scheduler syscalls to support an extended scheduling parameters ABI")
Link: http://lkml.kernel.org/r/20140115113015.GB31570@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fengguang Wu's kbuild test robot reported the following new htmldocs warnings:
>>> Warning(kernel/sched/core.c:3380): No description found for parameter 'uattr'
>>> Warning(kernel/sched/core.c:3380): Excess function parameter 'attr' description in 'sys_sched_setattr'
>>> Warning(kernel/sched/core.c:3520): No description found for parameter 'uattr'
>>> Warning(kernel/sched/core.c:3520): Excess function parameter 'attr' description in 'sys_sched_getattr'
The second argument to sys_sched_{setattr,getattr}() is named uattr (not attr).
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Juri Lelli <juri.lelli@gmail.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Dario Faggioli <raistlin@linux.it>
Fixes: d50dde5a10 ("sched: Add new scheduler syscalls to support an extended scheduling parameters ABI")
Link: http://lkml.kernel.org/r/52D5552D.5000102@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dan Carpenter reported new 'Smatch' warnings:
> tree: git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git sched/core
> head: 130816ce4d
> commit: 1baca4ce16 [17/50] sched/deadline: Add SCHED_DEADLINE SMP-related data structures & logic
>
> kernel/sched/deadline.c:937 pick_next_task_dl() warn: variable dereferenced before check 'p' (see line 934)
BUG_ON() already fires if pick_next_dl_entity() doesn't return a valid
dl_se. No need to check if p is valid afterward.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Juri Lelli <juri.lelli@gmail.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Fixes: 1baca4ce16 ("sched/deadline: Add SCHED_DEADLINE SMP-related data structures & logic")
Link: http://lkml.kernel.org/r/52D54E25.6060100@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
fix these new sparse warnings:
>> kernel/sched/core.c:305:14: sparse: symbol 'sysctl_sched_dl_period' was not declared. Should it be static?
>> kernel/sched/core.c:306:5: sparse: symbol 'sysctl_sched_dl_runtime' was not declared. Should it be static?
Better still, they're completely unused so remove them.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@gmail.com>
Link: http://lkml.kernel.org/n/tip-ke0shkG7vMnzmcdqhhiymyem@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
new sparse warnings:
>> kernel/sched/cpudeadline.c:38:6: sparse: symbol 'cpudl_exchange' was not declared. Should it be static?
>> kernel/sched/cpudeadline.c:46:6: sparse: symbol 'cpudl_heapify' was not declared. Should it be static?
>> kernel/sched/cpudeadline.c:71:6: sparse: symbol 'cpudl_change_key' was not declared. Should it be static?
>> kernel/sched/cpudeadline.c:195:15: sparse: memset with byte count of 163928
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@gmail.com>
Fixes: 6bfd6d72f5 ("sched/deadline: speed up SCHED_DEADLINE pushes with a push-heap")
Link: http://lkml.kernel.org/r/52d47f8c.EYJsA5+mELPBk4t6\%fengguang.wu@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fengguang Wu's kbuild test robot reported the following new m68k warnings:
In file included from drivers/nubus/nubus.c:22:0:
>> arch/m68k/include/asm/mac_via.h:262:47: warning: 'struct irq_desc' declared inside parameter list [enabled by default]
>> arch/m68k/include/asm/mac_via.h:262:47: warning: its scope is only this definition or declaration, which is probably not what you want [enabled by default]
Caused by the reworking of the generic local_bh{dis,en}able() code.
To fix it, forward declare 'struct irq_desc'.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Fixes: c795eb55e740 ("sched/preempt, locking: Rework local_bh_{dis,en}able()")
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: geert@linux-m68k.org
Link: http://lkml.kernel.org/r/20140112212456.GQ7572@laptop.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On AMD family 10h we see following error messages while waking up from
S3 for all non-boot CPUs leading to a failed IBS initialization:
Enabling non-boot CPUs ...
smpboot: Booting Node 0 Processor 1 APIC 0x1
[Firmware Bug]: cpu 1, try to use APIC500 (LVT offset 0) for vector 0x400, but the register is already in use for vector 0xf9 on another cpu
perf: IBS APIC setup failed on cpu #1
process: Switch to broadcast mode on CPU1
CPU1 is up
...
ACPI: Waking up from system sleep state S3
Reason for this is that during suspend the LVT offset for the IBS
vector gets lost and needs to be reinialized while resuming.
The offset is read from the IBSCTL msr. On family 10h the offset needs
to be 1 as offset 0 is used for the MCE threshold interrupt, but
firmware assings it for IBS to 0 too. The kernel needs to reprogram
the vector. The msr is a readonly node msr, but a new value can be
written via pci config space access. The reinitialization is
implemented for family 10h in setup_ibs_ctl() which is forced during
IBS setup.
This patch fixes IBS setup after waking up from S3 by adding
resume/supend hooks for the boot cpu which does the offset
reinitialization.
Marking it as stable to let distros pick up this fix.
Signed-off-by: Robert Richter <rric@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org> v3.2..
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1389797849-5565-1-git-send-email-rric.net@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Waiman managed to trigger a PMI while in a emulate_vsyscall() fault,
the PMI in turn managed to trigger a fault while obtaining a stack
trace. This triggered the sig_on_uaccess_error recursive fault logic
and killed the process dead.
Fix this by explicitly excluding interrupts from the recursive fault
logic.
Reported-and-Tested-by: Waiman Long <waiman.long@hp.com>
Fixes: e00b12e64b ("perf/x86: Further optimize copy_from_user_nmi()")
Cc: Aswin Chandramouleeswaran <aswin@hp.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140110200603.GJ7572@laptop.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On SoCs that have the calibration MSRs available, either there is no
PIT, HPET or PMTIMER to calibrate against, or the PIT/HPET/PMTIMER is
driven from the same clock as the TSC, so calibration is redundant and
just slows down the boot.
TSC rate is caculated by this formula:
<maximum core-clock to bus-clock ratio> * <maximum resolved frequency>
The ratio and the resolved frequency ID can be obtained from MSR.
See Intel 64 and IA-32 System Programming Guid section 16.12 and 30.11.5
for details.
Signed-off-by: Bin Gao <bin.gao@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/n/tip-rgm7xmg7k6qnjlw3ynkcjsmh@git.kernel.org
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=64791
When a cpu is downed on a system, the irqs on the cpu are assigned to
other cpus. It is possible, however, that when a cpu is downed there
aren't enough free vectors on the remaining cpus to account for the
vectors from the cpu that is being downed.
This results in an interesting "overflow" condition where irqs are
"assigned" to a CPU but are not handled.
For example, when downing cpus on a 1-64 logical processor system:
<snip>
[ 232.021745] smpboot: CPU 61 is now offline
[ 238.480275] smpboot: CPU 62 is now offline
[ 245.991080] ------------[ cut here ]------------
[ 245.996270] WARNING: CPU: 0 PID: 0 at net/sched/sch_generic.c:264 dev_watchdog+0x246/0x250()
[ 246.005688] NETDEV WATCHDOG: p786p1 (ixgbe): transmit queue 0 timed out
[ 246.013070] Modules linked in: lockd sunrpc iTCO_wdt iTCO_vendor_support sb_edac ixgbe microcode e1000e pcspkr joydev edac_core lpc_ich ioatdma ptp mdio mfd_core i2c_i801 dca pps_core i2c_core wmi acpi_cpufreq isci libsas scsi_transport_sas
[ 246.037633] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.12.0+ #14
[ 246.044451] Hardware name: Intel Corporation S4600LH ........../SVRBD-ROW_T, BIOS SE5C600.86B.01.08.0003.022620131521 02/26/2013
[ 246.057371] 0000000000000009 ffff88081fa03d40 ffffffff8164fbf6 ffff88081fa0ee48
[ 246.065728] ffff88081fa03d90 ffff88081fa03d80 ffffffff81054ecc ffff88081fa13040
[ 246.074073] 0000000000000000 ffff88200cce0000 0000000000000040 0000000000000000
[ 246.082430] Call Trace:
[ 246.085174] <IRQ> [<ffffffff8164fbf6>] dump_stack+0x46/0x58
[ 246.091633] [<ffffffff81054ecc>] warn_slowpath_common+0x8c/0xc0
[ 246.098352] [<ffffffff81054fb6>] warn_slowpath_fmt+0x46/0x50
[ 246.104786] [<ffffffff815710d6>] dev_watchdog+0x246/0x250
[ 246.110923] [<ffffffff81570e90>] ? dev_deactivate_queue.constprop.31+0x80/0x80
[ 246.119097] [<ffffffff8106092a>] call_timer_fn+0x3a/0x110
[ 246.125224] [<ffffffff8106280f>] ? update_process_times+0x6f/0x80
[ 246.132137] [<ffffffff81570e90>] ? dev_deactivate_queue.constprop.31+0x80/0x80
[ 246.140308] [<ffffffff81061db0>] run_timer_softirq+0x1f0/0x2a0
[ 246.146933] [<ffffffff81059a80>] __do_softirq+0xe0/0x220
[ 246.152976] [<ffffffff8165fedc>] call_softirq+0x1c/0x30
[ 246.158920] [<ffffffff810045f5>] do_softirq+0x55/0x90
[ 246.164670] [<ffffffff81059d35>] irq_exit+0xa5/0xb0
[ 246.170227] [<ffffffff8166062a>] smp_apic_timer_interrupt+0x4a/0x60
[ 246.177324] [<ffffffff8165f40a>] apic_timer_interrupt+0x6a/0x70
[ 246.184041] <EOI> [<ffffffff81505a1b>] ? cpuidle_enter_state+0x5b/0xe0
[ 246.191559] [<ffffffff81505a17>] ? cpuidle_enter_state+0x57/0xe0
[ 246.198374] [<ffffffff81505b5d>] cpuidle_idle_call+0xbd/0x200
[ 246.204900] [<ffffffff8100b7ae>] arch_cpu_idle+0xe/0x30
[ 246.210846] [<ffffffff810a47b0>] cpu_startup_entry+0xd0/0x250
[ 246.217371] [<ffffffff81646b47>] rest_init+0x77/0x80
[ 246.223028] [<ffffffff81d09e8e>] start_kernel+0x3ee/0x3fb
[ 246.229165] [<ffffffff81d0989f>] ? repair_env_string+0x5e/0x5e
[ 246.235787] [<ffffffff81d095a5>] x86_64_start_reservations+0x2a/0x2c
[ 246.242990] [<ffffffff81d0969f>] x86_64_start_kernel+0xf8/0xfc
[ 246.249610] ---[ end trace fb74fdef54d79039 ]---
[ 246.254807] ixgbe 0000:c2:00.0 p786p1: initiating reset due to tx timeout
[ 246.262489] ixgbe 0000:c2:00.0 p786p1: Reset adapter
Last login: Mon Nov 11 08:35:14 from 10.18.17.119
[root@(none) ~]# [ 246.792676] ixgbe 0000:c2:00.0 p786p1: detected SFP+: 5
[ 249.231598] ixgbe 0000:c2:00.0 p786p1: NIC Link is Up 10 Gbps, Flow Control: RX/TX
[ 246.792676] ixgbe 0000:c2:00.0 p786p1: detected SFP+: 5
[ 249.231598] ixgbe 0000:c2:00.0 p786p1: NIC Link is Up 10 Gbps, Flow Control: RX/TX
(last lines keep repeating. ixgbe driver is dead until module reload.)
If the downed cpu has more vectors than are free on the remaining cpus on the
system, it is possible that some vectors are "orphaned" even though they are
assigned to a cpu. In this case, since the ixgbe driver had a watchdog, the
watchdog fired and notified that something was wrong.
This patch adds a function, check_vectors(), to compare the number of vectors
on the CPU going down and compares it to the number of vectors available on
the system. If there aren't enough vectors for the CPU to go down, an
error is returned and propogated back to userspace.
v2: Do not need to look at percpu irqs
v3: Need to check affinity to prevent counting of MSIs in IOAPIC Lowest
Priority Mode
v4: Additional changes suggested by Gong Chen.
v5/v6/v7/v8: Updated comment text
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Link: http://lkml.kernel.org/r/1389613861-3853-1-git-send-email-prarit@redhat.com
Reviewed-by: Gong Chen <gong.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: Yang Zhang <yang.z.zhang@Intel.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Janet Morgan <janet.morgan@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Ruiv Wang <ruiv.wang@gmail.com>
Cc: Gong Chen <gong.chen@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@vger.kernel.org>
Pull scheduler and timer fixes from Ingo Molnar:
"Contains a fix for a scheduler bug that manifested itself as a 3D
performance regression and a crash fix for the ARM Cadence TTC clock
driver"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Calculate effective load even if local weight is 0
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
clocksource: cadence_ttc: Fix mutex taken inside interrupt context
Pull locking fixes from Ingo Molnar:
"Two fixes from lockdep coverage of seqlocks, which fix deadlocks on
lockdep-enabled ARM systems"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched_clock: Disable seqlock lockdep usage in sched_clock()
seqlock: Use raw_ prefix instead of _no_lockdep
Pull ARM fixes from Russell King:
"Another few fixes for ARM, nothing major here"
* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
ARM: 7938/1: OMAP4/highbank: Flush L2 cache before disabling
ARM: 7939/1: traps: fix opcode endianness when read from user memory
ARM: 7937/1: perf_event: Silence sparse warning
ARM: 7934/1: DT/kernel: fix arch_match_cpu_phys_id to avoid erroneous match
Revert "ARM: 7908/1: mm: Fix the arm_dma_limit calculation"
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Merge tag 'writeback-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux
Pull writeback fix from Wu Fengguang:
"Fix data corruption on NFS writeback.
It has been in linux-next for one month"
* tag 'writeback-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux:
writeback: Fix data corruption on NFS
Pull i2c bugfix from Wolfram Sang.
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: Re-instate body of i2c_parent_is_i2c_adapter()
At first Jakub Zawadzki noticed that some divisions by reciprocal_divide
were not correct. (off by one in some cases)
http://www.wireshark.org/~darkjames/reciprocal-buggy.c
He could also show this with BPF:
http://www.wireshark.org/~darkjames/set-and-dump-filter-k-bug.c
The reciprocal divide in linux kernel is not generic enough,
lets remove its use in BPF, as it is not worth the pain with
current cpus.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Jakub Zawadzki <darkjames-ws@darkjames.pl>
Cc: Mircea Gherzan <mgherzan@gmail.com>
Cc: Daniel Borkmann <dxchgb@gmail.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Matt Evans <matt@ozlabs.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The driver does not check value returned by dma_map_page. The patch
fixes this.
v2: Removed the bugfix for non-bug ;-) (thanks Sathya)
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Acked-by: Sathya Perla <Sathya.perla@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The bnx2x driver in its pci shutdown() callback releases its pci bars (in the
same manner it does during its pci remove() callback).
During a system reboot while VFs are enabled, its possible for the VF's remove
to be called (as a result of pci_disable_sriov()) after its shutdown callback
has already finished running; This will cause a paging request fault as the VF
tries to access the pci bar which it has previously released, crashing the
system.
This patch further differentiates the shutdown and remove callbacks, preventing the
pci release procedures from being called during shutdown.
Signed-off-by: Yuval Mintz <yuvalmin@broadcom.com>
Signed-off-by: Ariel Elior <ariele@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
rhine_reset_task() misses to disable the tx scheduler upon reset,
this can lead to a crash if work is still scheduled while we're resetting
the tx queue.
Fixes:
[ 93.591707] BUG: unable to handle kernel NULL pointer dereference at 0000004c
[ 93.595514] IP: [<c119d10d>] rhine_napipoll+0x491/0x6
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: David S. Miller <davem@davemloft.net>
Batman-adv prepends a full ethernet header in addition to its own
header. This has to be reflected in the MTU calculation, especially
since the value is used to set dev->hard_header_len.
Introduced by 411d6ed93a
("batman-adv: consider network coding overhead when calculating required mtu")
Reported-by: cmsv <cmsv@wirelesspt.net>
Reported-by: Martin Hundebøll <martin@hundeboll.net>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
We want to support all Intel MID (Mobile Internet Device) platforms
with a single config selection. This patch removes deprecated
CONFIG_X86_MDFLD and X86_WANT_INTEL_MID options in favor of having
CONFIG_X86_INTEL_MID only.
Signed-off-by: David Cohen <david.a.cohen@linux.intel.com>
Link: http://lkml.kernel.org/r/1387244246-20714-1-git-send-email-david.a.cohen@linux.intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
This code was partially based on Mark Brown's previous work.
Signed-off-by: David Cohen <david.a.cohen@linux.intel.com>
Link: http://lkml.kernel.org/r/1387224459-25746-4-git-send-email-david.a.cohen@linux.intel.com
Signed-off-by: Fei Yang <fei.yang@intel.com>
Cc: Mark F. Brown <mark.f.brown@intel.com>
Cc: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
This patch adds Clovertrail support on intel-mid and makes it more
flexible to support other SoCs.
Signed-off-by: David Cohen <david.a.cohen@linux.intel.com>
Link: http://lkml.kernel.org/r/1387224459-25746-3-git-send-email-david.a.cohen@linux.intel.com
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Fei Yang <fei.yang@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
In order make the driver more portable and support other Intel MID
(Mobile Internet Device) platforms we need to move Medfield code from
intel-mid.c core to its own mfld.c file.
This patch contains no functional changes.
Signed-off-by: David Cohen <david.a.cohen@linux.intel.com>
Link: http://lkml.kernel.org/r/1387224459-25746-2-git-send-email-david.a.cohen@linux.intel.com
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Make disabled_cpu_apicid static and read_mostly, and fix a couple of
typos.
Reported-by: Ingo Molnar <mingo@kernel.org>
Link: http://lkml.kernel.org/r/20140115182511.GA22737@gmail.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
The scsi and cfg80211 plugins cast between unsigned long long and
pointers, which is problematic for architectures where unsigned long
long is wider than the native pointer size:
linux/tools/lib/traceevent/plugin_scsi.c: In function ‘process_scsi_trace_parse_cdb’:
linux/tools/lib/traceevent/plugin_scsi.c:408:26: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
scsi_trace_parse_cdb(s, (unsigned char *) args[1], args[2]);
linux/tools/lib/traceevent/plugin_cfg80211.c: In function ‘process___le16_to_cpup’:
linux/tools/lib/traceevent/plugin_cfg80211.c:11:18: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
uint16_t *val = (uint16_t *) args[0];
This patch adds an intermediate cast to unsigned long, silencing the
warning.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/1389782648-4417-3-git-send-email-mark.rutland@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The hist_entry__add_cpumode_period() and hist_entry__decay() functions
are dealing with hist_entry's stat fields only.
Make them he_stat methods then.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Arun Sharma <asharma@fb.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Rodrigo Campos <rodrigo@sdfg.com.ar>
Link: http://lkml.kernel.org/r/1389677157-30513-5-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The report__resolve_callchain() can be shared with perf top code as it
doesn't really depend on the perf report code. Factor it out as
sample__resolve_callchain(). The same goes to the hist_entry__append_
callchain() too.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Arun Sharma <asharma@fb.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Rodrigo Campos <rodrigo@sdfg.com.ar>
Link: http://lkml.kernel.org/r/1389677157-30513-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The machine__resolve_callchain() is called only if symbol_conf.
use_callchain is set so no need to check it again.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Rodrigo Campos <rodrigo@sdfg.com.ar>
Link: http://lkml.kernel.org/r/1389677157-30513-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently the feature-checks Makefile does not inherit $(CC), and calls
cc rather than $(CROSS_COMPILE)gcc. Thus the feature checks invoke the
native toolchain rather than the cross toolchain, and can identify
features as available when they are not. This can break the build.
Additionally the native pkg-config is always called as opposed to
$(CROSS_COMPILE)pkg-config, so the wrong flags and paths may be passed
to the cross compiler.
This patch passes CROSS_COMPILE down to the feature-checks Makefile, and
forces its use. Additionally pkg-config is replaced with
$(CROSS_COMPILE)pkg-config via a new $(PKG_CONFIG) variable. This patch
has been build tested on x86_64 and arm.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/1389782648-4417-4-git-send-email-mark.rutland@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The PEVENT_PLUGIN_UNLOADER function might need some cleanup using pevent
like unregister some handlers. So pass pevent as argument.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1389750340-15965-6-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Now all of its users were gone. :)
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1389750340-15965-5-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Use plain malloc() and check its return value.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1389750340-15965-4-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If realloc() fails, it'll leak the buffer. Also increate buffer size
only if the allocation succeeded.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1389750340-15965-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The trace_seq->state is for tracking errors during the use of trace_seq
APIs and getting rid of die() in it.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/87fvopalbb.fsf@sejong.aot.lge.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It failed to build perf on my ubuntu 10.04 box (gcc 4.4.3):
CC util/strlist.o
cc1: warnings being treated as errors
util/strlist.c: In function ‘str_node__delete’:
util/strlist.c:42: error: dereferencing type-punned pointer will break strict-aliasing rules
util/strlist.c:42: error: dereferencing type-punned pointer will break strict-aliasing rules
CC util/strfilter.o
make: *** [util/strlist.o] Error 1
CC util/srcline.o
cc1: warnings being treated as errors
util/srcline.c: In function ‘addr2line_init’:
util/srcline.c:132: error: dereferencing type-punned pointer will break strict-aliasing rules
util/srcline.c:132: error: dereferencing type-punned pointer will break strict-aliasing rules
util/srcline.c: In function ‘addr2line_cleanup’:
util/srcline.c:143: error: dereferencing type-punned pointer will break strict-aliasing rules
util/srcline.c:143: error: dereferencing type-punned pointer will break strict-aliasing rules
make: *** [util/srcline.o] Error 1
It seems it only allows to remove 'const' qualifier.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1389276479-9047-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add disable_cpu_apicid kernel parameter. To use this kernel parameter,
specify an initial APIC ID of the corresponding CPU you want to
disable.
This is mostly used for the kdump 2nd kernel to disable BSP to wake up
multiple CPUs without causing system reset or hang due to sending INIT
from AP to BSP.
Kdump users first figure out initial APIC ID of the BSP, CPU0 in the
1st kernel, for example from /proc/cpuinfo and then set up this kernel
parameter for the 2nd kernel using the obtained APIC ID.
However, doing this procedure at each boot time manually is awkward,
which should be automatically done by user-land service scripts, for
example, kexec-tools on fedora/RHEL distributions.
This design is more flexible than disabling BSP in kernel boot time
automatically in that in kernel boot time we have no choice but
referring to ACPI/MP table to obtain initial APIC ID for BSP, meaning
that the method is not applicable to the systems without such BIOS
tables.
One assumption behind this design is that users get initial APIC ID of
the BSP in still healthy state and so BSP is uniquely kept in
CPU0. Thus, through the kernel parameter, only one initial APIC ID can
be specified.
In a comparison with disabled_cpu_apicid, we use read_apic_id(), not
boot_cpu_physical_apicid, because on some platforms, the variable is
modified to the apicid reported as BSP through MP table and this
function is executed with the temporarily modified
boot_cpu_physical_apicid. As a result, disabled_cpu_apicid kernel
parameter doesn't work well for apicids of APs.
Fixing the wrong handling of boot_cpu_physical_apicid requires some
reviews and tests beyond some platforms and it could take some
time. The fix here is a kind of workaround to focus on the main topic
of this patch.
Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Link: http://lkml.kernel.org/r/20140115064458.1545.38775.stgit@localhost6.localdomain6
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Commit e66d2ae7c6 moved the assignment
vcpu->arch.apic_base = value above a condition with
(vcpu->arch.apic_base ^ value), causing that check
to always fail. Use old_value, vcpu->arch.apic_base's
old value, in the condition instead.
Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Having u32 and struct cpuinfo_x86 * by the same name is not very smart,
although it was ok in this case due to the limited scope of u32 c and it
being used only once in there.
Fix this.
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1389786735-16751-1-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Merge patches from Andrew Morton:
"Six fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
lib/percpu_counter.c: fix __percpu_counter_add()
crash_dump: fix compilation error (on MIPS at least)
mm: fix crash when using XFS on loopback
MIPS: fix blast_icache32 on loongson2
MIPS: fix case mismatch in local_r4k_flush_icache_range()
nilfs2: fix segctor bug that causes file system corruption
All of these fix real bugs the people have hit, and are tagged
for -stable.
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Merge tag 'md/3.13-fixes' of git://neil.brown.name/md
Pull late md fixes from Neil Brown:
"Half a dozen md bug fixes.
All of these fix real bugs the people have hit, and are tagged for
-stable. Sorry they are late .... Christmas holidays and all that.
Hopefully they can still squeak into 3.13"
* tag 'md/3.13-fixes' of git://neil.brown.name/md:
md: fix problem when adding device to read-only array with bitmap.
md/raid10: fix bug when raid10 recovery fails to recover a block.
md/raid5: fix a recently broken BUG_ON().
md/raid1: fix request counting bug in new 'barrier' code.
md/raid10: fix two bugs in handling of known-bad-blocks.
md/raid5: Fix possible confusion when multiple write errors occur.
Pull drm fixes from Dave Airlie:
"One nouveau regression fix on older cards, i915 black screen fixes,
and a revert for a strange G33 intel problem"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/nouveau: fix null ptr dereferences on some boards
Revert "drm: copy mode type in drm_mode_connector_list_update()"
drm/i915/bdw: make sure south port interrupts are enabled properly v2
drm/i915: Don't grab crtc mutexes in intel_modeset_gem_init()
drm/i915: fix DDI PLLs HW state readout code
__percpu_counter_add() may be called in softirq/hardirq handler (such
as, blk_mq_queue_exit() is typically called in hardirq/softirq handler),
so we need to call this_cpu_add()(irq safe helper) to update percpu
counter, otherwise counts may be lost.
This fixes the problem that 'rmmod null_blk' hangs in blk_cleanup_queue()
because of miscounting of request_queue->mq_usage_counter.
This patch is the v1 of previous one of "lib/percpu_counter.c:
disable local irq when updating percpu couter", and takes Andrew's
approach which may be more efficient for ARCHs(x86, s390) that
have optimized this_cpu_add().
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Shaohua Li <shli@fusionio.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Fan Du <fan.du@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In file included from kernel/crash_dump.c:2:0:
include/linux/crash_dump.h:22:27: error: unknown type name `pgprot_t'
when CONFIG_CRASH_DUMP=y
The error was traced back to commit 9cb218131d ("vmcore: introduce
remap_oldmem_pfn_range()")
include <asm/pgtable.h> to get the missing definition
Signed-off-by: Qais Yousef <qais.yousef@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Cc: <stable@vger.kernel.org> [3.12+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 8456a648cf ("slab: use struct page for slab management") causes
a crash in the LVM2 testsuite on PA-RISC (the crashing test is
fsadm.sh). The testsuite doesn't crash on 3.12, crashes on 3.13-rc1 and
later.
Bad Address (null pointer deref?): Code=15 regs=000000413edd89a0 (Addr=000006202224647d)
CPU: 3 PID: 24008 Comm: loop0 Not tainted 3.13.0-rc6 #5
task: 00000001bf3c0048 ti: 000000413edd8000 task.ti: 000000413edd8000
YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI
PSW: 00001000000001101111100100001110 Not tainted
r00-03 000000ff0806f90e 00000000405c8de0 000000004013e6c0 000000413edd83f0
r04-07 00000000405a95e0 0000000000000200 00000001414735f0 00000001bf349e40
r08-11 0000000010fe3d10 0000000000000001 00000040829c7778 000000413efd9000
r12-15 0000000000000000 000000004060d800 0000000010fe3000 0000000010fe3000
r16-19 000000413edd82a0 00000041078ddbc0 0000000000000010 0000000000000001
r20-23 0008f3d0d83a8000 0000000000000000 00000040829c7778 0000000000000080
r24-27 00000001bf349e40 00000001bf349e40 202d66202224640d 00000000405a95e0
r28-31 202d662022246465 000000413edd88f0 000000413edd89a0 0000000000000001
sr00-03 000000000532c000 0000000000000000 0000000000000000 000000000532c000
sr04-07 0000000000000000 0000000000000000 0000000000000000 0000000000000000
IASQ: 0000000000000000 0000000000000000 IAOQ: 00000000401fe42c 00000000401fe430
IIR: 539c0030 ISR: 00000000202d6000 IOR: 000006202224647d
CPU: 3 CR30: 000000413edd8000 CR31: 0000000000000000
ORIG_R28: 00000000405a95e0
IAOQ[0]: vma_interval_tree_iter_first+0x14/0x48
IAOQ[1]: vma_interval_tree_iter_first+0x18/0x48
RP(r2): flush_dcache_page+0x128/0x388
Backtrace:
flush_dcache_page+0x128/0x388
lo_splice_actor+0x90/0x148 [loop]
splice_from_pipe_feed+0xc0/0x1d0
__splice_from_pipe+0xac/0xc0
lo_direct_splice_actor+0x1c/0x70 [loop]
splice_direct_to_actor+0xec/0x228
lo_receive+0xe4/0x298 [loop]
loop_thread+0x478/0x640 [loop]
kthread+0x134/0x168
end_fault_vector+0x20/0x28
xfs_setsize_buftarg+0x0/0x90 [xfs]
Kernel panic - not syncing: Bad Address (null pointer deref?)
Commit 8456a648cf changes the page structure so that the slab
subsystem reuses the page->mapping field.
The crash happens in the following way:
* XFS allocates some memory from slab and issues a bio to read data
into it.
* the bio is sent to the loopback device.
* lo_receive creates an actor and calls splice_direct_to_actor.
* lo_splice_actor copies data to the target page.
* lo_splice_actor calls flush_dcache_page because the page may be
mapped by userspace. In that case we need to flush the kernel cache.
* flush_dcache_page asks for the list of userspace mappings, however
that page->mapping field is reused by the slab subsystem for a
different purpose. This causes the crash.
Note that other architectures without coherent caches (sparc, arm, mips)
also call page_mapping from flush_dcache_page, so they may crash in the
same way.
This patch fixes this bug by testing if the page is a slab page in
page_mapping and returning NULL if it is.
The patch also fixes VM_BUG_ON(PageSlab(page)) that could happen in
earlier kernels in the same scenario on architectures without cache
coherence when CONFIG_DEBUG_VM is enabled - so it should be backported
to stable kernels.
In the old kernels, the function page_mapping is placed in
include/linux/mm.h, so you should modify the patch accordingly when
backporting it.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: John David Anglin <dave.anglin@bell.net>]
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Lameter <cl@linux.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Reviewed-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
