06 Oct, 2010
2 commits
-
…/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
rcu: rcu_read_lock_bh_held(): disabling irqs also disables bh
generic-ipi: Fix deadlock in __smp_call_function_single -
With all the recent module loading cleanups, we've minimized the code
that sits under module_mutex, fixing various deadlocks and making it
possible to do most of the module loading in parallel.However, that whole conversion totally missed the rather obscure code
that adds a new module to the list for BUG() handling. That code was
doubly obscure because (a) the code itself lives in lib/bugs.c (for
dubious reasons) and (b) it gets called from the architecture-specific
"module_finalize()" rather than from generic code.Calling it from arch-specific code makes no sense what-so-ever to begin
with, and is now actively wrong since that code isn't protected by the
module loading lock any more.So this commit moves the "module_bug_{finalize,cleanup}()" calls away
from the arch-specific code, and into the generic code - and in the
process protects it with the module_mutex so that the list operations
are now safe.Future fixups:
- move the module list handling code into kernel/module.c where it
belongs.
- get rid of 'module_bug_list' and just use the regular list of modules
(called 'modules' - imagine that) that we already create and maintain
for other reasons.Reported-and-tested-by: Thomas Gleixner
Cc: Rusty Russell
Cc: Adrian Bunk
Cc: Andrew Morton
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds
02 Oct, 2010
1 commit
-
The kfifo_dma family of functions use sg_mark_end() on the last element in
their scatterlist. This forces use of a fresh scatterlist for each DMA
operation, which makes recycling a single scatterlist impossible.Change the behavior of the kfifo_dma functions to match the usage of the
dma_map_sg function. This means that users must respect the returned
nents value. The sample code is updated to reflect the change.This bug is trivial to cause: call kfifo_dma_in_prepare() such that it
prepares a scatterlist with a single entry comprising the whole fifo.
This is the case when you map the entirety of a newly created empty fifo.
This causes the setup_sgl() function to mark the first scatterlist entry
as the end of the chain, no matter what comes after it.Afterwards, add and remove some data from the fifo such that another call
to kfifo_dma_in_prepare() will create two scatterlist entries. It returns
nents=2. However, due to the previous sg_mark_end() call, sg_is_last()
will now return true for the first scatterlist element. This causes the
sample code to print a single scatterlist element when it should print
two.By removing the call to sg_mark_end(), we make the API as similar as
possible to the DMA mapping API. All users are required to respect the
returned nents.Signed-off-by: Ira W. Snyder
Cc: Stefani Seibold
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
23 Sep, 2010
1 commit
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The below bug in fork led to the rmap walk finding the parent huge-pmd
twice instead of just once, because the anon_vma_chain objects of the
child vma still point to the vma->vm_mm of the parent.The patch fixes it by making the rmap walk accurate during fork. It's not
a big deal normally but it worth being accurate considering the cost is
the same.Signed-off-by: Andrea Arcangeli
Acked-by: Johannes Weiner
Acked-by: Rik van Riel
Acked-by: Hugh Dickins
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
22 Sep, 2010
2 commits
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…l/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
sched: Fix nohz balance kick
sched: Fix user time incorrectly accounted as system time on 32-bit -
…/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
hw breakpoints: Fix pid namespace bug
x86: Fix instruction breakpoint encoding
oprofile: Add Support for Intel CPU Family 6 / Model 22 (Intel Celeron 540)
kprobes: Fix Kconfig dependency
21 Sep, 2010
1 commit
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There's a situation where the nohz balancer will try to wake itself:
cpu-x is idle which is also ilb_cpu
got a scheduler tick during idle
and the nohz_kick_needed() in trigger_load_balance() checks for
rq_x->nr_running which might not be zero (because of someone waking a
task on this rq etc) and this leads to the situation of the cpu-x
sending a kick to itself.And this can cause a lockup.
Avoid this by not marking ourself eligible for kicking.
Signed-off-by: Suresh Siddha
Signed-off-by: Peter Zijlstra
LKML-Reference:
Signed-off-by: Ingo Molnar
17 Sep, 2010
2 commits
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Hardware breakpoints can't be registered within pid namespaces
because tsk->pid is passed rather than the pid in the current
namespace.(See https://bugzilla.kernel.org/show_bug.cgi?id=17281 )
This is a quick fix demonstrating the problem but is not the
best method of solving the problem since passing pids internally
is not the best way to avoid pid namespace bugs. Subsequent patches
will show a better solution.Much thanks to Frederic Weisbecker for doing
the bulk of the work finding this bug.Reported-by: Robin Green
Signed-off-by: Matt Helsley
Signed-off-by: Peter Zijlstra
Cc: Prasad
Cc: Arnaldo Carvalho de Melo
Cc: Steven Rostedt
Cc: Will Deacon
Cc: Mahesh Salgaonkar
Cc: 2.6.33-2.6.35
LKML-Reference:
Signed-off-by: Ingo Molnar
Signed-off-by: Frederic Weisbecker -
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: add documentation
15 Sep, 2010
2 commits
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We have 32-bit variable overflow possibility when multiply in
task_times() and thread_group_times() functions. When the
overflow happens then the scaled utime value becomes erroneously
small and the scaled stime becomes i erroneously big.Reported here:
https://bugzilla.redhat.com/show_bug.cgi?id=633037
https://bugzilla.kernel.org/show_bug.cgi?id=16559Reported-by: Michael Chapman
Reported-by: Ciriaco Garcia de Celis
Signed-off-by: Stanislaw Gruszka
Signed-off-by: Peter Zijlstra
Cc: Hidetoshi Seto
Cc: # 2.6.32.19+ (partially) and 2.6.33+
LKML-Reference:
Signed-off-by: Ingo Molnar -
compat_alloc_user_space() expects the caller to independently call
access_ok() to verify the returned area. A missing call could
introduce problems on some architectures.This patch incorporates the access_ok() check into
compat_alloc_user_space() and also adds a sanity check on the length.
The existing compat_alloc_user_space() implementations are renamed
arch_compat_alloc_user_space() and are used as part of the
implementation of the new global function.This patch assumes NULL will cause __get_user()/__put_user() to either
fail or access userspace on all architectures. This should be
followed by checking the return value of compat_access_user_space()
for NULL in the callers, at which time the access_ok() in the callers
can also be removed.Reported-by: Ben Hawkes
Signed-off-by: H. Peter Anvin
Acked-by: Benjamin Herrenschmidt
Acked-by: Chris Metcalf
Acked-by: David S. Miller
Acked-by: Ingo Molnar
Acked-by: Thomas Gleixner
Acked-by: Tony Luck
Cc: Andrew Morton
Cc: Arnd Bergmann
Cc: Fenghua Yu
Cc: H. Peter Anvin
Cc: Heiko Carstens
Cc: Helge Deller
Cc: James Bottomley
Cc: Kyle McMartin
Cc: Martin Schwidefsky
Cc: Paul Mackerras
Cc: Ralf Baechle
Cc:
14 Sep, 2010
1 commit
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Mathieu reported bad latencies with make -j10 kind of kbuild
workloads - which is mostly caused by us scheduling with a
too coarse granularity.Reduce the minimum granularity some more, to make sure we
can meet the latency target.I got the following results (make -j10 kbuild load, average of 3
runs):vanilla:
maximum latency: 38278.9 µs
average latency: 7730.1 µspatched:
maximum latency: 22702.1 µs
average latency: 6684.8 µsMathieu also measured it:
|
| * wakeup-latency.c (SIGEV_THREAD) with make -j10
|
| - Mainline 2.6.35.2 kernel
|
| maximum latency: 45762.1 µs
| average latency: 7348.6 µs
|
| - With only Peter's smaller min_gran (shown below):
|
| maximum latency: 29100.6 µs
| average latency: 6684.1 µs
|Reported-by: Mathieu Desnoyers
Reported-by: Linus Torvalds
Acked-by: Mathieu Desnoyers
Suggested-by: Peter Zijlstra
Acked-by: Peter Zijlstra
LKML-Reference:
Signed-off-by: Ingo Molnar
13 Sep, 2010
1 commit
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Update copyright notice and add Documentation/workqueue.txt.
Randy Dunlap, Dave Chinner: misc fixes.
Signed-off-by: Tejun Heo
Reviewed-By: Florian Mickler
Cc: Ingo Molnar
Cc: Christoph Lameter
Cc: Randy Dunlap
Cc: Dave Chinner
12 Sep, 2010
2 commits
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* 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6:
PM / Hibernate: Avoid hitting OOM during preallocation of memory
PM QoS: Correct pr_debug() misuse and improve parameter checks
PM: Prevent waiting forever on asynchronous resume after failing suspend -
There is a problem in hibernate_preallocate_memory() that it calls
preallocate_image_memory() with an argument that may be greater than
the total number of available non-highmem memory pages. If that's
the case, the OOM condition is guaranteed to trigger, which in turn
can cause significant slowdown to occur during hibernation.To avoid that, make preallocate_image_memory() adjust its argument
before calling preallocate_image_pages(), so that the total number of
saveable non-highem pages left is not less than the minimum size of
a hibernation image. Change hibernate_preallocate_memory() to try to
allocate from highmem if the number of pages allocated by
preallocate_image_memory() is too low.Modify free_unnecessary_pages() to take all possible memory
allocation patterns into account.Reported-by: KOSAKI Motohiro
Signed-off-by: Rafael J. Wysocki
Tested-by: M. Vefa Bicakci
11 Sep, 2010
2 commits
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…l/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, tsc: Fix a preemption leak in restore_sched_clock_state()
sched: Move sched_avg_update() to update_cpu_load() -
Correct some pr_debug() misuse and add a stronger parameter check to
pm_qos_write() for the ASCII hex value case. Thanks to Dan Carpenter
for pointing out the problem!Signed-off-by: mark gross
Signed-off-by: Rafael J. Wysocki
10 Sep, 2010
10 commits
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Just got my 6 way machine to a state where cpu 0 is in an
endless loop within __smp_call_function_single.
All other cpus are idle.The call trace on cpu 0 looks like this:
__smp_call_function_single
scheduler_tick
update_process_times
tick_sched_timer
__run_hrtimer
hrtimer_interrupt
clock_comparator_work
do_extint
ext_int_handler
----> timer irq
cpu_idle__smp_call_function_single() got called from nohz_balancer_kick()
(inlined) with the remote cpu being 1, wait being 0 and the per
cpu variable remote_sched_softirq_cb (call_single_data) of the
current cpu (0).Then it loops forever when it tries to grab the lock of the
call_single_data, since it is already locked and enqueued on cpu 0.My theory how this could have happened: for some reason the
scheduler decided to call __smp_call_function_single() on it's own
cpu, and sends an IPI to itself. The interrupt stays pending
since IRQs are disabled. If then the hypervisor schedules the
cpu away it might happen that upon rescheduling both the IPI and
the timer IRQ are pending. If then interrupts are enabled again
it depends which one gets scheduled first.
If the timer interrupt gets delivered first we end up with the
local deadlock as seen in the calltrace above.Let's make __smp_call_function_single() check if the target cpu is
the current cpu and execute the function immediately just like
smp_call_function_single does. That should prevent at least the
scenario described here.It might also be that the scheduler is not supposed to call
__smp_call_function_single with the remote cpu being the current
cpu, but that is a different issue.Signed-off-by: Heiko Carstens
Acked-by: Peter Zijlstra
Acked-by: Jens Axboe
Cc: Venkatesh Pallipadi
Cc: Suresh Siddha
LKML-Reference:
Signed-off-by: Ingo Molnar -
…/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
tracing: t_start: reset FTRACE_ITER_HASH in case of seek/pread
perf symbols: Fix multiple initialization of symbol system
perf: Fix CPU hotplug
perf, trace: Fix module leak
tracing/kprobe: Fix handling of C-unlike argument names
tracing/kprobes: Fix handling of argument names
perf probe: Fix handling of arguments names
perf probe: Fix return probe support
tracing/kprobe: Fix a memory leak in error case
tracing: Do not allow llseek to set_ftrace_filter -
Be sure to avoid entering t_show() with FTRACE_ITER_HASH set without
having properly started the iterator to iterate the hash. This case is
degenerate and, as discovered by Robert Swiecki, can cause t_hash_show()
to misuse a pointer. This causes a NULL ptr deref with possible security
implications. Tracked as CVE-2010-3079.Cc: Robert Swiecki
Cc: Eugene Teo
Cc:
Signed-off-by: Chris Wright
Signed-off-by: Steven Rostedt -
Please revert 2.6.36-rc commit d2997b1042ec150616c1963b5e5e919ffd0b0ebf
"hibernation: freeze swap at hibernation". It complicated matters by
adding a second swap allocation path, just for hibernation; without in any
way fixing the issue that it was intended to address - page reclaim after
fixing the hibernation image might free swap from a page already imaged as
swapcache, letting its swap be reallocated to store a different page of
the image: resulting in data corruption if the imaged page were freed as
clean then swapped back in. Pages freed to si->swap_map were still in
danger of being reallocated by the alternative allocation path.I guess it inadvertently fixed slow SSD swap allocation for hibernation,
as reported by Nigel Cunningham: by missing out the discards that occur on
the usual swap allocation path; but that was unintentional, and needs a
separate fix.Signed-off-by: Hugh Dickins
Cc: KAMEZAWA Hiroyuki
Cc: KOSAKI Motohiro
Cc: "Rafael J. Wysocki"
Cc: Ondrej Zary
Cc: Andrea Gelmini
Cc: Balbir Singh
Cc: Andrea Arcangeli
Cc: Nigel Cunningham
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
gid_t is a unsigned int. If group_info contains a gid greater than
MAX_INT, groups_search() function may look on the wrong side of the search
tree.This solves some unfair "permission denied" problems.
Signed-off-by: Jerome Marchand
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Add cgroup_attach_task_all()
The existing cgroup_attach_task_current_cg() API is called by a thread to
attach another thread to all of its cgroups; this is unsuitable for cases
where a privileged task wants to attach itself to the cgroups of a less
privileged one, since the call must be made from the context of the target
task.This patch adds a more generic cgroup_attach_task_all() API that allows
both the source task and to-be-moved task to be specified.
cgroup_attach_task_current_cg() becomes a specialization of the more
generic new function.[menage@google.com: rewrote changelog]
[akpm@linux-foundation.org: address reviewer comments]
Signed-off-by: Michael S. Tsirkin
Tested-by: Alex Williamson
Acked-by: Paul Menage
Cc: Li Zefan
Cc: Ben Blum
Cc: Sridhar Samudrala
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The gcov-kernel infrastructure expects that each object file is loaded
only once. This may not be true, e.g. when loading multiple kernel
modules which are linked to the same object file. As a result, loading
such kernel modules will result in incorrect gcov results while unloading
will cause a null-pointer dereference.This patch fixes these problems by changing the gcov-kernel infrastructure
so that multiple profiling data sets can be associated with one debugfs
entry. It applies to 2.6.36-rc1.Signed-off-by: Peter Oberparleiter
Reported-by: Werner Spies
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Currently sched_avg_update() (which updates rt_avg stats in the rq)
is getting called from scale_rt_power() (in the load balance context)
which doesn't take rq->lock.Fix it by moving the sched_avg_update() to more appropriate
update_cpu_load() where the CFS load gets updated as well.Signed-off-by: Suresh Siddha
Signed-off-by: Peter Zijlstra
LKML-Reference:
Signed-off-by: Ingo Molnar -
Since we have UP_PREPARE, we should also have UP_CANCELED.
Signed-off-by: Peter Zijlstra
Cc: paulus
LKML-Reference:
Signed-off-by: Ingo Molnar -
Commit 1c024eca (perf, trace: Optimize tracepoints by using
per-tracepoint-per-cpu hlist to track events) caused a module
refcount leak.Reported-And-Tested-by: Avi Kivity
Signed-off-by: Peter Zijlstra
LKML-Reference:
Signed-off-by: Ingo Molnar
09 Sep, 2010
3 commits
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…/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
gcc-4.6: kernel/*: Fix unused but set warnings
mutex: Fix annotations to include it in kernel-locking docbook
pid: make setpgid() system call use RCU read-side critical section
MAINTAINERS: Add RCU's public git tree -
…/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
perf, x86: Try to handle unknown nmis with an enabled PMU
perf, x86: Fix handle_irq return values
perf, x86: Fix accidentally ack'ing a second event on intel perf counter
oprofile, x86: fix init_sysfs() function stub
lockup_detector: Sync touch_*_watchdog back to old semantics
tracing: Fix a race in function profile
oprofile, x86: fix init_sysfs error handling
perf_events: Fix time tracking for events with pid != -1 and cpu != -1
perf: Initialize callchains roots's childen hits
oprofile: fix crash when accessing freed task structs -
Reading the file set_ftrace_filter does three things.
1) shows whether or not filters are set for the function tracer
2) shows what functions are set for the function tracer
3) shows what triggers are set on any functions3 is independent from 1 and 2.
The way this file currently works is that it is a state machine,
and as you read it, it may change state. But this assumption breaks
when you use lseek() on the file. The state machine gets out of sync
and the t_show() may use the wrong pointer and cause a kernel oops.Luckily, this will only kill the app that does the lseek, but the app
dies while holding a mutex. This prevents anyone else from using the
set_ftrace_filter file (or any other function tracing file for that matter).A real fix for this is to rewrite the code, but that is too much for
a -rc release or stable. This patch simply disables llseek on the
set_ftrace_filter() file for now, and we can do the proper fix for the
next major release.Reported-by: Robert Swiecki
Cc: Chris Wright
Cc: Tavis Ormandy
Cc: Eugene Teo
Cc: vendor-sec@lst.de
Cc:
Signed-off-by: Steven Rostedt
08 Sep, 2010
4 commits
-
Check the argument name whether it is invalid (not C-like symbol name). This
makes event format simple.Reported-by: Srikar Dronamraju
Cc: Steven Rostedt
Cc: Frederic Weisbecker
Cc: Ingo Molnar
Cc: Mathieu Desnoyers
LKML-Reference:
Signed-off-by: Masami Hiramatsu
Signed-off-by: Arnaldo Carvalho de Melo -
Set "argN" name for each argument automatically if it has no specified name.
Since dynamic trace event(kprobe_events) accepts special characters for its
argument, its format can show those special characters (e.g. '$', '%', '+').
However, perf can't parse those format because of the character (especially
'%') mess up the format. This sets "argX" name for those arguments if user
omitted the argument names.E.g.
# echo 'p do_fork %ax IP=%ip $stack' > tracing/kprobe_events
# cat tracing/kprobe_events
p:kprobes/p_do_fork_0 do_fork arg1=%ax IP=%ip arg3=$stackReported-by: Srikar Dronamraju
Cc: Steven Rostedt
Cc: Frederic Weisbecker
Cc: Ingo Molnar
Cc: Mathieu Desnoyers
LKML-Reference:
Signed-off-by: Masami Hiramatsu
Signed-off-by: Arnaldo Carvalho de Melo -
Fix a memory leak which happens when a field name conflicts with others. In
error case, free_trace_probe() will free all arguments until nr_args, so this
increments nr_args the begining of the loop instead of the end.Cc: Steven Rostedt
Cc: Frederic Weisbecker
Cc: Ingo Molnar
Cc: Mathieu Desnoyers
LKML-Reference:
Signed-off-by: Masami Hiramatsu
Signed-off-by: Arnaldo Carvalho de Melo -
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: use zalloc_cpumask_var() for gcwq->mayday_mask
workqueue: fix GCWQ_DISASSOCIATED initialization
workqueue: Add a workqueue chapter to the tracepoint docbook
workqueue: fix cwq->nr_active underflow
workqueue: improve destroy_workqueue() debuggability
workqueue: mark lock acquisition on worker_maybe_bind_and_lock()
workqueue: annotate lock context change
workqueue: free rescuer on destroy_workqueue
05 Sep, 2010
1 commit
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No real bugs I believe, just some dead code.
Signed-off-by: Andi Kleen
Cc: Peter Zijlstra
Cc: andi@firstfloor.org
Signed-off-by: Andrew Morton
Signed-off-by: Ingo Molnar
03 Sep, 2010
1 commit
-
Fix kernel-doc notation in linux/mutex.h and kernel/mutex.c,
then add these 2 files to the kernel-locking docbook as the
Mutex API reference chapter.Add one API function to mutex-design.txt and correct a typo in
that file.Signed-off-by: Randy Dunlap
Cc: Rusty Russell
LKML-Reference:
Signed-off-by: Ingo Molnar
01 Sep, 2010
3 commits
-
During my rewrite, the semantics of touch_nmi_watchdog and
touch_softlockup_watchdog changed enough to break some drivers
(mostly over preemptable regions).These are cases where long delays on one CPU (due to
print_delay for example) can cause long delays on other
CPUs - so we must 'touch' the nmi_watchdog flag of those
other CPUs as well.This change brings those touch_*_watchdog() functions back in line
with to how they used to work.Signed-off-by: Don Zickus
Acked-by: Cyrill Gorcunov
Cc: peterz@infradead.org
Cc: fweisbec@gmail.com
LKML-Reference:
Signed-off-by: Ingo Molnar -
[ 23.584719]
[ 23.584720] ===================================================
[ 23.585059] [ INFO: suspicious rcu_dereference_check() usage. ]
[ 23.585176] ---------------------------------------------------
[ 23.585176] kernel/pid.c:419 invoked rcu_dereference_check() without protection!
[ 23.585176]
[ 23.585176] other info that might help us debug this:
[ 23.585176]
[ 23.585176]
[ 23.585176] rcu_scheduler_active = 1, debug_locks = 1
[ 23.585176] 1 lock held by rc.sysinit/728:
[ 23.585176] #0: (tasklist_lock){.+.+..}, at: [] sys_setpgid+0x5f/0x193
[ 23.585176]
[ 23.585176] stack backtrace:
[ 23.585176] Pid: 728, comm: rc.sysinit Not tainted 2.6.36-rc2 #2
[ 23.585176] Call Trace:
[ 23.585176] [] lockdep_rcu_dereference+0x99/0xa2
[ 23.585176] [] find_task_by_pid_ns+0x50/0x6a
[ 23.585176] [] find_task_by_vpid+0x1d/0x1f
[ 23.585176] [] sys_setpgid+0x67/0x193
[ 23.585176] [] system_call_fastpath+0x16/0x1b
[ 24.959669] type=1400 audit(1282938522.956:4): avc: denied { module_request } for pid=766 comm="hwclock" kmod="char-major-10-135" scontext=system_u:system_r:hwclock_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclasIt turns out that the setpgid() system call fails to enter an RCU
read-side critical section before doing a PID-to-task_struct translation.
This commit therefore does rcu_read_lock() before the translation, and
also does rcu_read_unlock() after the last use of the returned pointer.Reported-by: Andrew Morton
Signed-off-by: Paul E. McKenney
Acked-by: David Howells -
While we are reading trace_stat/functionX and someone just
disabled function_profile at that time, we can trigger this:divide error: 0000 [#1] PREEMPT SMP
...
EIP is at function_stat_show+0x90/0x230
...This fix just takes the ftrace_profile_lock and checks if
rec->counter is 0. If it's 0, we know the profile buffer
has been reset.Signed-off-by: Li Zefan
Cc: stable@kernel.org
LKML-Reference:
Signed-off-by: Steven Rostedt
31 Aug, 2010
1 commit
-
alloc_mayday_mask() was using alloc_cpumask_var() making
gcwq->mayday_mask contain garbage after initialization on
CONFIG_CPUMASK_OFFSTACK=y configurations. This combined with the
previously fixed GCWQ_DISASSOCIATED initialization bug could make
rescuers fall into infinite loop trying to bind to an offline cpu.Signed-off-by: Tejun Heo
Reported-by: CAI Qian