| Commit message (Collapse) | Author | Age | Files | Lines |
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Pull networking fixes from David Miller:
1) There was a simplification in the ipv6 ndisc packet sending
attempted here, which avoided using memory accounting on the
per-netns ndisc socket for sending NDISC packets. It did fix some
important issues, but it causes regressions so it gets reverted here
too. Specifically, the problem with this change is that the IPV6
output path really depends upon there being a valid skb->sk
attached.
The reason we want to do this change in some form when we figure out
how to do it right, is that if a device goes down the ndisc_sk
socket send queue will fill up and block NDISC packets that we want
to send to other devices too. That's really bad behavior.
Hopefully Thomas can come up with a better version of this change.
2) Fix a severe TCP performance regression by reverting a change made
to dev_pick_tx() quite some time ago. From Eric Dumazet.
3) TIPC returns wrongly signed error codes, fix from Erik Hugne.
4) Fix OOPS when doing IPSEC over ipv4 tunnels due to orphaning the
skb->sk too early. Fix from Li Hongjun.
5) RAW ipv4 sockets can use the wrong routing key during lookup, from
Chris Clark.
6) Similar to #1 revert an older change that tried to use plain
alloc_skb() for SYN/ACK TCP packets, this broke the netfilter owner
mark which needs to see the skb->sk for such frames. From Phil
Oester.
7) BNX2x driver bug fixes from Ariel Elior and Yuval Mintz,
specifically in the handling of virtual functions.
8) IPSEC path error propagations to sockets is not done properly when
we have v4 in v6, and v6 in v4 type rules. Fix from Hannes Frederic
Sowa.
9) Fix missing channel context release in mac80211, from Johannes Berg.
10) Fix network namespace handing wrt. SCM_RIGHTS, from Andy
Lutomirski.
11) Fix usage of bogus NAPI weight in jme, netxen, and ps3_gelic
drivers. From Michal Schmidt.
12) Hopefully a complete and correct fix for the genetlink dump locking
and module reference counting. From Pravin B Shelar.
13) sk_busy_loop() must do a cpu_relax(), from Eliezer Tamir.
14) Fix handling of timestamp offset when restoring a snapshotted TCP
socket. From Andrew Vagin.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (44 commits)
net: fec: fix time stamping logic after napi conversion
net: bridge: convert MLDv2 Query MRC into msecs_to_jiffies for max_delay
mISDN: return -EINVAL on error in dsp_control_req()
net: revert 8728c544a9c ("net: dev_pick_tx() fix")
Revert "ipv6: Don't depend on per socket memory for neighbour discovery messages"
ipv4 tunnels: fix an oops when using ipip/sit with IPsec
tipc: set sk_err correctly when connection fails
tcp: tcp_make_synack() should use sock_wmalloc
bridge: separate querier and query timer into IGMP/IPv4 and MLD/IPv6 ones
ipv6: Don't depend on per socket memory for neighbour discovery messages
ipv4: sendto/hdrincl: don't use destination address found in header
tcp: don't apply tsoffset if rcv_tsecr is zero
tcp: initialize rcv_tstamp for restored sockets
net: xilinx: fix memleak
net: usb: Add HP hs2434 device to ZLP exception table
net: add cpu_relax to busy poll loop
net: stmmac: fixed the pbl setting with DT
genl: Hold reference on correct module while netlink-dump.
genl: Fix genl dumpit() locking.
xfrm: Fix potential null pointer dereference in xdst_queue_output
...
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nsproxy.pid_ns is *not* the task's pid namespace. The name should clarify
that.
This makes it more obvious that setns on a pid namespace is weird --
it won't change the pid namespace shown in procfs.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fix from Tejun Heo:
"During the percpu reference counting update which was merged during
v3.11-rc1, the cgroup destruction path was updated so that a cgroup in
the process of dying may linger on the children list, which was
necessary as the cgroup should still be included in child/descendant
iteration while percpu ref is being killed.
Unfortunately, I forgot to update cgroup destruction path accordingly
and cgroup destruction may fail spuriously with -EBUSY due to
lingering dying children even when there's no live child left - e.g.
"rmdir parent/child parent" will usually fail.
This can be easily fixed by iterating through the children list to
verify that there's no live child left. While this is very late in
the release cycle, this bug is very visible to userland and I believe
the fix is relatively safe.
Thanks Hugh for spotting and providing fix for the issue"
* 'for-3.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: fix rmdir EBUSY regression in 3.11
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On 3.11-rc we are seeing cgroup directories left behind when they should
have been removed. Here's a trivial reproducer:
cd /sys/fs/cgroup/memory
mkdir parent parent/child; rmdir parent/child parent
rmdir: failed to remove `parent': Device or resource busy
It's because cgroup_destroy_locked() (step 1 of destruction) leaves
cgroup on parent's children list, letting cgroup_offline_fn() (step 2 of
destruction) remove it; but step 2 is run by work queue, which may not
yet have removed the children when parent destruction checks the list.
Fix that by checking through a non-empty list of children: if every one
of them has already been marked CGRP_DEAD, then it's safe to proceed:
those children are invisible to userspace, and should not obstruct rmdir.
(I didn't see any reason to keep the cgrp->children checks under the
unrelated css_set_lock, so moved them out.)
tj: Flattened nested ifs a bit and updated comment so that it's
correct on both for-3.11-fixes and for-3.12.
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
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If !PREEMPT, a kworker running work items back to back can hog CPU.
This becomes dangerous when a self-requeueing work item which is
waiting for something to happen races against stop_machine. Such
self-requeueing work item would requeue itself indefinitely hogging
the kworker and CPU it's running on while stop_machine would wait for
that CPU to enter stop_machine while preventing anything else from
happening on all other CPUs. The two would deadlock.
Jamie Liu reports that this deadlock scenario exists around
scsi_requeue_run_queue() and libata port multiplier support, where one
port may exclude command processing from other ports. With the right
timing, scsi_requeue_run_queue() can end up requeueing itself trying
to execute an IO which is asked to be retried while another device has
an exclusive access, which in turn can't make forward progress due to
stop_machine.
Fix it by invoking cond_resched() after executing each work item.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Jamie Liu <jamieliu@google.com>
References: http://thread.gmane.org/gmane.linux.kernel/1552567
Cc: stable@vger.kernel.org
--
kernel/workqueue.c | 9 +++++++++
1 file changed, 9 insertions(+)
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Correct an issue with /proc/timer_list reported by Holger.
When reading from the proc file with a sufficiently small buffer, 2k so
not really that small, there was one could get hung trying to read the
file a chunk at a time.
The timer_list_start function failed to account for the possibility that
the offset was adjusted outside the timer_list_next.
Signed-off-by: Nathan Zimmer <nzimmer@sgi.com>
Reported-by: Holger Hans Peter Freyther <holger@freyther.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Berke Durak <berke.durak@xiphos.com>
Cc: Jeff Layton <jlayton@redhat.com>
Tested-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org> # 3.10.x
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fix from Tejun Heo:
"A late fix for cgroup.
This fixes a behavior regression visible to userland which was created
by a commit merged during -rc1. While the behavior change isn't too
likely to be noticeable, the fix is relatively low risk and we'll need
to backport it through -stable anyway if the bug gets released"
* 'for-3.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cpuset: fix a regression in validating config change
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It's not allowed to clear masks of a cpuset if there're tasks in it,
but it's broken:
# mkdir /cgroup/sub
# echo 0 > /cgroup/sub/cpuset.cpus
# echo 0 > /cgroup/sub/cpuset.mems
# echo $$ > /cgroup/sub/tasks
# echo > /cgroup/sub/cpuset.cpus
(should fail)
This bug was introduced by commit 88fa523bff295f1d60244a54833480b02f775152
("cpuset: allow to move tasks to empty cpusets").
tj: Dropped temp bool variables and nestes the conditionals directly.
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Ingo Molnar:
"Three small fixlets"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
nohz: fix compile warning in tick_nohz_init()
nohz: Do not warn about unstable tsc unless user uses nohz_full
sched_clock: Fix integer overflow
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git://git.linaro.org/people/jstultz/linux into timers/urgent
Pull small fix for v3.11 from John Stultz.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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The expression '(1 << 32)' happens to evaluate as 0 on ARM, but
it evaluates as 1 on xtensa and x86_64. This zeros sched_clock_mask,
and breaks sched_clock().
Set the type of 1 to 'unsigned long long' to get the value we need.
Reported-by: Max Filippov <jcmvbkbc@gmail.com>
Tested-by: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: John Stultz <john.stultz@linaro.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks into timers/urgent
Pull nohz fixes from Frederic Weisbecker.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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cpu is not used after commit 5b8621a68fdcd2baf1d3b413726f913a5254d46a
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
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If the user enables CONFIG_NO_HZ_FULL and runs the kernel on a machine
with an unstable TSC, it will produce a WARN_ON dump as well as taint
the kernel. This is a bit extreme for a kernel that just enables a
feature but doesn't use it.
The warning should only happen if the user tries to use the feature by
either adding nohz_full to the kernel command line, or by enabling
CONFIG_NO_HZ_FULL_ALL that makes nohz used on all CPUs at boot up. Note,
this second feature should not (yet) be used by distros or anyone that
doesn't care if NO_HZ is used or not.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
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Fix new kernel-doc warnings in kernel/wait.c:
Warning(kernel/wait.c:374): No description found for parameter 'p'
Warning(kernel/wait.c:374): Excess function parameter 'word' description in 'wake_up_atomic_t'
Warning(kernel/wait.c:374): Excess function parameter 'bit' description in 'wake_up_atomic_t'
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fix from Tejun Heo:
"This contains one patch to fix the return value of cpuset's cgroups
interface function, which used to always return -ENODEV for the writes
on the 'memory_pressure_enabled' file"
* 'for-3.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cpuset: fix the return value of cpuset_write_u64()
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Writing to this file always returns -ENODEV:
# echo 1 > cpuset.memory_pressure_enabled
-bash: echo: write error: No such device
Signed-off-by: Li Zefan <lizefan@huawei.com>
Cc: <stable@vger.kernel.org> # 3.9+
Signed-off-by: Tejun Heo <tj@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fix from Rafael Wysocki:
"The removal of delayed_work_pending() checks from kernel/power/qos.c
done in 3.9 introduced a deadlock in pm_qos_work_fn().
Fix from Stephen Boyd"
* tag 'pm-3.11-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / QoS: Fix workqueue deadlock when using pm_qos_update_request_timeout()
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pm_qos_update_request_timeout() updates a qos and then schedules
a delayed work item to bring the qos back down to the default
after the timeout. When the work item runs, pm_qos_work_fn() will
call pm_qos_update_request() and deadlock because it tries to
cancel itself via cancel_delayed_work_sync(). Future callers of
that qos will also hang waiting to cancel the work that is
canceling itself. Let's extract the little bit of code that does
the real work of pm_qos_update_request() and call it from the
work function so that we don't deadlock.
Before ed1ac6e (PM: don't use [delayed_]work_pending()) this didn't
happen because the work function wouldn't try to cancel itself.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Reviewed-by: Tejun Heo <tj@kernel.org>
Cc: 3.9+ <stable@vger.kernel.org> # 3.9+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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Merge a bunch of fixes from Andrew Morton.
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
fs/proc/task_mmu.c: fix buffer overflow in add_page_map()
arch: *: Kconfig: add "kernel/Kconfig.freezer" to "arch/*/Kconfig"
ocfs2: fix null pointer dereference in ocfs2_dir_foreach_blk_id()
x86 get_unmapped_area(): use proper mmap base for bottom-up direction
ocfs2: fix NULL pointer dereference in ocfs2_duplicate_clusters_by_page
ocfs2: Revert 40bd62e to avoid regression in extended allocation
drivers/rtc/rtc-stmp3xxx.c: provide timeout for potentially endless loop polling a HW bit
hugetlb: fix lockdep splat caused by pmd sharing
aoe: adjust ref of head for compound page tails
microblaze: fix clone syscall
mm: save soft-dirty bits on file pages
mm: save soft-dirty bits on swapped pages
memcg: don't initialize kmem-cache destroying work for root caches
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Fix inadvertent breakage in the clone syscall ABI for Microblaze that
was introduced in commit f3268edbe6fe ("microblaze: switch to generic
fork/vfork/clone").
The Microblaze syscall ABI for clone takes the parent tid address in the
4th argument; the third argument slot is used for the stack size. The
incorrectly-used CLONE_BACKWARDS type assigned parent tid to the 3rd
slot.
This commit restores the original ABI so that existing userspace libc
code will work correctly.
All kernel versions from v3.8-rc1 were affected.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
"Docbook fixes that make 99% of the diffstat, plus a oneliner fix"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Ensure update_cfs_shares() is called for parents of continuously-running tasks
sched: Fix some kernel-doc warnings
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continuously-running tasks
We typically update a task_group's shares within the dequeue/enqueue
path. However, continuously running tasks sharing a CPU are not
subject to these updates as they are only put/picked. Unfortunately,
when we reverted f269ae046 (in 17bc14b7), we lost the augmenting
periodic update that was supposed to account for this; resulting in a
potential loss of fairness.
To fix this, re-introduce the explicit update in
update_cfs_rq_blocked_load() [called via entity_tick()].
Reported-by: Max Hailperin <max@gustavus.edu>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Paul Turner <pjt@google.com>
Link: http://lkml.kernel.org/n/tip-9545m3apw5d93ubyrotrj31y@git.kernel.org
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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When building the htmldocs (in verbose mode), scripts/kernel-doc
reports the follwing type of warnings:
Warning(kernel/sched/core.c:936): No description found for return value of 'task_curr'
...
Fix those by:
- adding the missing descriptions
- using "Return" sections for the descriptions
Signed-off-by: Yacine Belkadi <yacine.belkadi.1@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1373654747-2389-1-git-send-email-yacine.belkadi.1@gmail.com
[ While at it, fix the cpupri_set() explanation. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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This is only theoretical, but after try_to_wake_up(p) was changed
to check p->state under p->pi_lock the code like
__set_current_state(TASK_INTERRUPTIBLE);
schedule();
can miss a signal. This is the special case of wait-for-condition,
it relies on try_to_wake_up/schedule interaction and thus it does
not need mb() between __set_current_state() and if(signal_pending).
However, this __set_current_state() can move into the critical
section protected by rq->lock, now that try_to_wake_up() takes
another lock we need to ensure that it can't be reordered with
"if (signal_pending(current))" check inside that section.
The patch is actually one-liner, it simply adds smp_wmb() before
spin_lock_irq(rq->lock). This is what try_to_wake_up() already
does by the same reason.
We turn this wmb() into the new helper, smp_mb__before_spinlock(),
for better documentation and to allow the architectures to change
the default implementation.
While at it, kill smp_mb__after_lock(), it has no callers.
Perhaps we can also add smp_mb__before/after_spinunlock() for
prepare_to_wait().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull w/w mutex deadlock injection fix from Ingo Molnar.
This bug made the CONFIG_DEBUG_WW_MUTEX_SLOWPATH=y option largely
useless, but wouldn't affect normal users.
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
mutex: Fix w/w mutex deadlock injection
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The check needs to be for > 1, because ctx->acquired is already incremented.
This will prevent ww_mutex_lock_slow from returning -EDEADLK and not locking
the mutex. It caused a lot of false gpu lockups on radeon with
CONFIG_DEBUG_WW_MUTEX_SLOWPATH=y because a function that shouldn't be able
to return -EDEADLK did.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/51F775B5.201@canonical.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Ensure that user_namespace->parent chain can't grow too much.
Currently we use the hardroded 32 as limit.
Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Oleg Nesterov has been working hard in closing all the holes that can
lead to race conditions between deleting an event and accessing an
event debugfs file. This included a fix to the debugfs system (acked
by Greg Kroah-Hartman). We think that all the holes have been patched
and hopefully we don't find more. I haven't marked all of them for
stable because I need to examine them more to figure out how far back
some of the changes need to go.
Along the way, some other fixes have been made. Alexander Z Lam fixed
some logic where the wrong buffer was being modifed.
Andrew Vagin found a possible corruption for machines that actually
allocate cpumask, as a reference to one was being zeroed out by
mistake.
Dhaval Giani found a bad prototype when tracing is not configured.
And I not only had some changes to help Oleg, but also finally fixed a
long standing bug that Dave Jones and others have been hitting, where
a module unload and reload can cause the function tracing accounting
to get screwed up"
* tag 'trace-fixes-3.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix reset of time stamps during trace_clock changes
tracing: Make TRACE_ITER_STOP_ON_FREE stop the correct buffer
tracing: Fix trace_dump_stack() proto when CONFIG_TRACING is not set
tracing: Fix fields of struct trace_iterator that are zeroed by mistake
tracing/uprobes: Fail to unregister if probe event files are in use
tracing/kprobes: Fail to unregister if probe event files are in use
tracing: Add comment to describe special break case in probe_remove_event_call()
tracing: trace_remove_event_call() should fail if call/file is in use
debugfs: debugfs_remove_recursive() must not rely on list_empty(d_subdirs)
ftrace: Check module functions being traced on reload
ftrace: Consolidate some duplicate code for updating ftrace ops
tracing: Change remove_event_file_dir() to clear "d_subdirs"->i_private
tracing: Introduce remove_event_file_dir()
tracing: Change f_start() to take event_mutex and verify i_private != NULL
tracing: Change event_filter_read/write to verify i_private != NULL
tracing: Change event_enable/disable_read() to verify i_private != NULL
tracing: Turn event/id->i_private into call->event.type
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Fixed two issues with changing the timestamp clock with trace_clock:
- The global buffer was reset on instance clock changes. Change this to pass
the correct per-instance buffer
- ftrace_now() is used to set buf->time_start in tracing_reset_online_cpus().
This was incorrect because ftrace_now() used the global buffer's clock to
return the current time. Change this to use buffer_ftrace_now() which
returns the current time for the correct per-instance buffer.
Also removed tracing_reset_current() because it is not used anywhere
Link: http://lkml.kernel.org/r/1375493777-17261-2-git-send-email-azl@google.com
Cc: Vaibhav Nagarnaik <vnagarnaik@google.com>
Cc: David Sharp <dhsharp@google.com>
Cc: Alexander Z Lam <lambchop468@gmail.com>
Cc: stable@vger.kernel.org # 3.10
Signed-off-by: Alexander Z Lam <azl@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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Releasing the free_buffer file in an instance causes the global buffer
to be stopped when TRACE_ITER_STOP_ON_FREE is enabled. Operate on the
correct buffer.
Link: http://lkml.kernel.org/r/1375493777-17261-1-git-send-email-azl@google.com
Cc: Vaibhav Nagarnaik <vnagarnaik@google.com>
Cc: David Sharp <dhsharp@google.com>
Cc: Alexander Z Lam <lambchop468@gmail.com>
Cc: stable@vger.kernel.org # 3.10
Signed-off-by: Alexander Z Lam <azl@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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tracing_read_pipe zeros all fields bellow "seq". The declaration contains
a comment about that, but it doesn't help.
The first field is "snapshot", it's true when current open file is
snapshot. Looks obvious, that it should not be zeroed.
The second field is "started". It was converted from cpumask_t to
cpumask_var_t (v2.6.28-4983-g4462344), in other words it was
converted from cpumask to pointer on cpumask.
Currently the reference on "started" memory is lost after the first read
from tracing_read_pipe and a proper object will never be freed.
The "started" is never dereferenced for trace_pipe, because trace_pipe
can't have the TRACE_FILE_ANNOTATE options.
Link: http://lkml.kernel.org/r/1375463803-3085183-1-git-send-email-avagin@openvz.org
Cc: stable@vger.kernel.org # 2.6.30
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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Uprobes suffer the same problem that kprobes have. There's a race between
writing to the "enable" file and removing the probe. The probe checks for
it being in use and if it is not, goes about deleting the probe and the
event that represents it. But the problem with that is, after it checks
if it is in use it can be enabled, and the deletion of the event (access
to the probe) will fail, as it is in use. But the uprobe will still be
deleted. This is a problem as the event can reference the uprobe that
was deleted.
The fix is to remove the event first, and check to make sure the event
removal succeeds. Then it is safe to remove the probe.
When the event exists, either ftrace or perf can enable the probe and
prevent the event from being removed.
Link: http://lkml.kernel.org/r/20130704034038.991525256@goodmis.org
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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When a probe is being removed, it cleans up the event files that correspond
to the probe. But there is a race between writing to one of these files
and deleting the probe. This is especially true for the "enable" file.
CPU 0 CPU 1
----- -----
fd = open("enable",O_WRONLY);
probes_open()
release_all_trace_probes()
unregister_trace_probe()
if (trace_probe_is_enabled(tp))
return -EBUSY
write(fd, "1", 1)
__ftrace_set_clr_event()
call->class->reg()
(kprobe_register)
enable_trace_probe(tp)
__unregister_trace_probe(tp);
list_del(&tp->list)
unregister_probe_event(tp) <-- fails!
free_trace_probe(tp)
write(fd, "0", 1)
__ftrace_set_clr_event()
call->class->unreg
(kprobe_register)
disable_trace_probe(tp) <-- BOOM!
A test program was written that used two threads to simulate the
above scenario adding a nanosleep() interval to change the timings
and after several thousand runs, it was able to trigger this bug
and crash:
BUG: unable to handle kernel paging request at 00000005000000f9
IP: [<ffffffff810dee70>] probes_open+0x3b/0xa7
PGD 7808a067 PUD 0
Oops: 0000 [#1] PREEMPT SMP
Dumping ftrace buffer:
---------------------------------
Modules linked in: ipt_MASQUERADE sunrpc ip6t_REJECT nf_conntrack_ipv6
CPU: 1 PID: 2070 Comm: test-kprobe-rem Not tainted 3.11.0-rc3-test+ #47
Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./To be filled by O.E.M., BIOS SDBLI944.86P 05/08/2007
task: ffff880077756440 ti: ffff880076e52000 task.ti: ffff880076e52000
RIP: 0010:[<ffffffff810dee70>] [<ffffffff810dee70>] probes_open+0x3b/0xa7
RSP: 0018:ffff880076e53c38 EFLAGS: 00010203
RAX: 0000000500000001 RBX: ffff88007844f440 RCX: 0000000000000003
RDX: 0000000000000003 RSI: 0000000000000003 RDI: ffff880076e52000
RBP: ffff880076e53c58 R08: ffff880076e53bd8 R09: 0000000000000000
R10: ffff880077756440 R11: 0000000000000006 R12: ffffffff810dee35
R13: ffff880079250418 R14: 0000000000000000 R15: ffff88007844f450
FS: 00007f87a276f700(0000) GS:ffff88007d480000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 00000005000000f9 CR3: 0000000077262000 CR4: 00000000000007e0
Stack:
ffff880076e53c58 ffffffff81219ea0 ffff88007844f440 ffffffff810dee35
ffff880076e53ca8 ffffffff81130f78 ffff8800772986c0 ffff8800796f93a0
ffffffff81d1b5d8 ffff880076e53e04 0000000000000000 ffff88007844f440
Call Trace:
[<ffffffff81219ea0>] ? security_file_open+0x2c/0x30
[<ffffffff810dee35>] ? unregister_trace_probe+0x4b/0x4b
[<ffffffff81130f78>] do_dentry_open+0x162/0x226
[<ffffffff81131186>] finish_open+0x46/0x54
[<ffffffff8113f30b>] do_last+0x7f6/0x996
[<ffffffff8113cc6f>] ? inode_permission+0x42/0x44
[<ffffffff8113f6dd>] path_openat+0x232/0x496
[<ffffffff8113fc30>] do_filp_open+0x3a/0x8a
[<ffffffff8114ab32>] ? __alloc_fd+0x168/0x17a
[<ffffffff81131f4e>] do_sys_open+0x70/0x102
[<ffffffff8108f06e>] ? trace_hardirqs_on_caller+0x160/0x197
[<ffffffff81131ffe>] SyS_open+0x1e/0x20
[<ffffffff81522742>] system_call_fastpath+0x16/0x1b
Code: e5 41 54 53 48 89 f3 48 83 ec 10 48 23 56 78 48 39 c2 75 6c 31 f6 48 c7
RIP [<ffffffff810dee70>] probes_open+0x3b/0xa7
RSP <ffff880076e53c38>
CR2: 00000005000000f9
---[ end trace 35f17d68fc569897 ]---
The unregister_trace_probe() must be done first, and if it fails it must
fail the removal of the kprobe.
Several changes have already been made by Oleg Nesterov and Masami Hiramatsu
to allow moving the unregister_probe_event() before the removal of
the probe and exit the function if it fails. This prevents the tp
structure from being used after it is freed.
Link: http://lkml.kernel.org/r/20130704034038.819592356@goodmis.org
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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The "break" used in the do_for_each_event_file() is used as an optimization
as the loop is really a double loop. The loop searches all event files
for each trace_array. There's only one matching event file per trace_array
and after we find the event file for the trace_array, the break is used
to jump to the next trace_array and start the search there.
As this is not a standard way of using "break" in C code, it requires
a comment right before the break to let people know what is going on.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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Change trace_remove_event_call(call) to return the error if this
call is active. This is what the callers assume but can't verify
outside of the tracing locks. Both trace_kprobe.c/trace_uprobe.c
need the additional changes, unregister_trace_probe() should abort
if trace_remove_event_call() fails.
The caller is going to free this call/file so we must ensure that
nobody can use them after trace_remove_event_call() succeeds.
debugfs should be fine after the previous changes and event_remove()
does TRACE_REG_UNREGISTER, but still there are 2 reasons why we need
the additional checks:
- There could be a perf_event(s) attached to this tp_event, so the
patch checks ->perf_refcount.
- TRACE_REG_UNREGISTER can be suppressed by FTRACE_EVENT_FL_SOFT_MODE,
so we simply check FTRACE_EVENT_FL_ENABLED protected by event_mutex.
Link: http://lkml.kernel.org/r/20130729175033.GB26284@redhat.com
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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There's been a nasty bug that would show up and not give much info.
The bug displayed the following warning:
WARNING: at kernel/trace/ftrace.c:1529 __ftrace_hash_rec_update+0x1e3/0x230()
Pid: 20903, comm: bash Tainted: G O 3.6.11+ #38405.trunk
Call Trace:
[<ffffffff8103e5ff>] warn_slowpath_common+0x7f/0xc0
[<ffffffff8103e65a>] warn_slowpath_null+0x1a/0x20
[<ffffffff810c2ee3>] __ftrace_hash_rec_update+0x1e3/0x230
[<ffffffff810c4f28>] ftrace_hash_move+0x28/0x1d0
[<ffffffff811401cc>] ? kfree+0x2c/0x110
[<ffffffff810c68ee>] ftrace_regex_release+0x8e/0x150
[<ffffffff81149f1e>] __fput+0xae/0x220
[<ffffffff8114a09e>] ____fput+0xe/0x10
[<ffffffff8105fa22>] task_work_run+0x72/0x90
[<ffffffff810028ec>] do_notify_resume+0x6c/0xc0
[<ffffffff8126596e>] ? trace_hardirqs_on_thunk+0x3a/0x3c
[<ffffffff815c0f88>] int_signal+0x12/0x17
---[ end trace 793179526ee09b2c ]---
It was finally narrowed down to unloading a module that was being traced.
It was actually more than that. When functions are being traced, there's
a table of all functions that have a ref count of the number of active
tracers attached to that function. When a function trace callback is
registered to a function, the function's record ref count is incremented.
When it is unregistered, the function's record ref count is decremented.
If an inconsistency is detected (ref count goes below zero) the above
warning is shown and the function tracing is permanently disabled until
reboot.
The ftrace callback ops holds a hash of functions that it filters on
(and/or filters off). If the hash is empty, the default means to filter
all functions (for the filter_hash) or to disable no functions (for the
notrace_hash).
When a module is unloaded, it frees the function records that represent
the module functions. These records exist on their own pages, that is
function records for one module will not exist on the same page as
function records for other modules or even the core kernel.
Now when a module unloads, the records that represents its functions are
freed. When the module is loaded again, the records are recreated with
a default ref count of zero (unless there's a callback that traces all
functions, then they will also be traced, and the ref count will be
incremented).
The problem is that if an ftrace callback hash includes functions of the
module being unloaded, those hash entries will not be removed. If the
module is reloaded in the same location, the hash entries still point
to the functions of the module but the module's ref counts do not reflect
that.
With the help of Steve and Joern, we found a reproducer:
Using uinput module and uinput_release function.
cd /sys/kernel/debug/tracing
modprobe uinput
echo uinput_release > set_ftrace_filter
echo function > current_tracer
rmmod uinput
modprobe uinput
# check /proc/modules to see if loaded in same addr, otherwise try again
echo nop > current_tracer
[BOOM]
The above loads the uinput module, which creates a table of functions that
can be traced within the module.
We add uinput_release to the filter_hash to trace just that function.
Enable function tracincg, which increments the ref count of the record
associated to uinput_release.
Remove uinput, which frees the records including the one that represents
uinput_release.
Load the uinput module again (and make sure it's at the same address).
This recreates the function records all with a ref count of zero,
including uinput_release.
Disable function tracing, which will decrement the ref count for uinput_release
which is now zero because of the module removal and reload, and we have
a mismatch (below zero ref count).
The solution is to check all currently tracing ftrace callbacks to see if any
are tracing any of the module's functions when a module is loaded (it already does
that with callbacks that trace all functions). If a callback happens to have
a module function being traced, it increments that records ref count and starts
tracing that function.
There may be a strange side effect with this, where tracing module functions
on unload and then reloading a new module may have that new module's functions
being traced. This may be something that confuses the user, but it's not
a big deal. Another approach is to disable all callback hashes on module unload,
but this leaves some ftrace callbacks that may not be registered, but can
still have hashes tracing the module's function where ftrace doesn't know about
it. That situation can cause the same bug. This solution solves that case too.
Another benefit of this solution, is it is possible to trace a module's
function on unload and load.
Link: http://lkml.kernel.org/r/20130705142629.GA325@redhat.com
Reported-by: Jörn Engel <joern@logfs.org>
Reported-by: Dave Jones <davej@redhat.com>
Reported-by: Steve Hodgson <steve@purestorage.com>
Tested-by: Steve Hodgson <steve@purestorage.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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When ftrace ops modifies the functions that it will trace, the update
to the function mcount callers may need to be modified. Consolidate
the two places that do the checks to see if an update is required
with a wrapper function for those checks.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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Change remove_event_file_dir() to clear ->i_private for every
file we are going to remove.
We need to check file->dir != NULL because event_create_dir()
can fail. debugfs_remove_recursive(NULL) is fine but the patch
moves it under the same check anyway for readability.
spin_lock(d_lock) and "d_inode != NULL" check are not needed
afaics, but I do not understand this code enough.
tracing_open_generic_file() and tracing_release_generic_file()
can go away, ftrace_enable_fops and ftrace_event_filter_fops()
use tracing_open_generic() but only to check tracing_disabled.
This fixes all races with event_remove() or instance_delete().
f_op->read/write/whatever can never use the freed file/call,
all event/* files were changed to check and use ->i_private
under event_mutex.
Note: this doesn't not fix other problems, event_remove() can
destroy the active ftrace_event_call, we need more changes but
those changes are completely orthogonal.
Link: http://lkml.kernel.org/r/20130728183527.GB16723@redhat.com
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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Preparation for the next patch. Extract the common code from
remove_event_from_tracers() and __trace_remove_event_dirs()
into the new helper, remove_event_file_dir().
The patch looks more complicated than it actually is, it also
moves remove_subsystem() up to avoid the forward declaration.
Link: http://lkml.kernel.org/r/20130726172547.GA3629@redhat.com
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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trace_format_open() and trace_format_seq_ops are racy, nothing
protects ftrace_event_call from trace_remove_event_call().
Change f_start() to take event_mutex and verify i_private != NULL,
change f_stop() to drop this lock.
This fixes nothing, but now we can change debugfs_remove("format")
callers to nullify ->i_private and fix the the problem.
Note: the usage of event_mutex is sub-optimal but simple, we can
change this later.
Link: http://lkml.kernel.org/r/20130726172543.GA3622@redhat.com
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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event_filter_read/write() are racy, ftrace_event_call can be already
freed by trace_remove_event_call() callers.
1. Shift mutex_lock(event_mutex) from print/apply_event_filter to
the callers.
2. Change the callers, event_filter_read() and event_filter_write()
to read i_private under this mutex and abort if it is NULL.
This fixes nothing, but now we can change debugfs_remove("filter")
callers to nullify ->i_private and fix the the problem.
Link: http://lkml.kernel.org/r/20130726172540.GA3619@redhat.com
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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tracing_open_generic_file() is racy, ftrace_event_file can be
already freed by rmdir or trace_remove_event_call().
Change event_enable_read() and event_disable_read() to read and
verify "file = i_private" under event_mutex.
This fixes nothing, but now we can change debugfs_remove("enable")
callers to nullify ->i_private and fix the the problem.
Link: http://lkml.kernel.org/r/20130726172536.GA3612@redhat.com
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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event_id_read() is racy, ftrace_event_call can be already freed
by trace_remove_event_call() callers.
Change event_create_dir() to pass "data = call->event.type", this
is all event_id_read() needs. ftrace_event_id_fops no longer needs
tracing_open_generic().
We add the new helper, event_file_data(), to read ->i_private, it
will have more users.
Note: currently ACCESS_ONCE() and "id != 0" check are not needed,
but we are going to change event_remove/rmdir to clear ->i_private.
Link: http://lkml.kernel.org/r/20130726172532.GA3605@redhat.com
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fix from Tejun Heo:
"Fix for a minor memory leak bug in the cgroup init failure path"
* 'for-3.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: fix a leak when percpu_ref_init() fails
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ss->css_free() is not called when perfcpu_ref_init() fails.
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull two workqueue fixes from Tejun Heo:
"A lockdep notation update so that nested work_on_cpu() invocations
don't lead to spurious lockdep warnings and fix for an unbound attr
bug which made what's shown in sysfs deviate from the actual ones.
Both patches have pretty limited scope"
* 'for-3.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: copy workqueue_attrs with all fields
workqueue: allow work_on_cpu() to be called recursively
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$echo '0' > /sys/bus/workqueue/devices/xxx/numa
$cat /sys/bus/workqueue/devices/xxx/numa
I got 1. It should be 0, the reason is copy_workqueue_attrs() called
in apply_workqueue_attrs() doesn't copy no_numa field.
Fix it by making copy_workqueue_attrs() copy ->no_numa too. This
would also make get_unbound_pool() set a pool's ->no_numa attribute
according to the workqueue attributes used when the pool was created.
While harmelss, as ->no_numa isn't a pool attribute, this is a bit
confusing. Clear it explicitly.
tj: Updated description and comments a bit.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org
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If the @fn call work_on_cpu() again, the lockdep will complain:
> [ INFO: possible recursive locking detected ]
> 3.11.0-rc1-lockdep-fix-a #6 Not tainted
> ---------------------------------------------
> kworker/0:1/142 is trying to acquire lock:
> ((&wfc.work)){+.+.+.}, at: [<ffffffff81077100>] flush_work+0x0/0xb0
>
> but task is already holding lock:
> ((&wfc.work)){+.+.+.}, at: [<ffffffff81075dd9>] process_one_work+0x169/0x610
>
> other info that might help us debug this:
> Possible unsafe locking scenario:
>
> CPU0
> ----
> lock((&wfc.work));
> lock((&wfc.work));
>
> *** DEADLOCK ***
It is false-positive lockdep report. In this sutiation,
the two "wfc"s of the two work_on_cpu() are different,
they are both on stack. flush_work() can't be deadlock.
To fix this, we need to avoid the lockdep checking in this case,
thus we instroduce a internal __flush_work() which skip the lockdep.
tj: Minor comment adjustment.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Reported-by: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Reported-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
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Some of my configs I test with have CONFIG_A11Y_BRAILLE_CONSOLE set.
When I started testing against v3.11-rc4 my console went bonkers. Using
ktest to bisect the issue, it came down to:
commit bbeddf52a "printk: move braille console support into separate
braille.[ch] files"
Looking into the patch I found the problem. It's with the return of
braille_register_console(). As anything other than NULL is considered a
failure.
But for those of us that have CONFIG_A11Y_BRAILLE_CONSOLE set but do not
define a "brl" or "brl=" on the command line, we still may want a
console that those with sight can still use.
Return NULL (success) if "brl" or "brl=" is not on the console line.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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