diff options
| author | Zqiang <qiang.zhang@windriver.com> | 2020-11-01 17:07:53 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-11-02 12:14:19 -0800 |
| commit | 6993d0fdbee0eb38bfac350aa016f65ad11ed3b1 (patch) | |
| tree | cad795370c775bae518a8a1fe2bdc35e1a4edb9e /kernel/kthread.c | |
| parent | a77eedbc871ee3b435bffc30b123b60eecca402c (diff) | |
kthread_worker: prevent queuing delayed work from timer_fn when it is being canceled
There is a small race window when a delayed work is being canceled and
the work still might be queued from the timer_fn:
CPU0 CPU1
kthread_cancel_delayed_work_sync()
__kthread_cancel_work_sync()
__kthread_cancel_work()
work->canceling++;
kthread_delayed_work_timer_fn()
kthread_insert_work();
BUG: kthread_insert_work() should not get called when work->canceling is
set.
Signed-off-by: Zqiang <qiang.zhang@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20201014083030.16895-1-qiang.zhang@windriver.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/kthread.c')
| -rw-r--r-- | kernel/kthread.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/kernel/kthread.c b/kernel/kthread.c index e29773c82b70..933a625621b8 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -897,7 +897,8 @@ void kthread_delayed_work_timer_fn(struct timer_list *t) /* Move the work from worker->delayed_work_list. */ WARN_ON_ONCE(list_empty(&work->node)); list_del_init(&work->node); - kthread_insert_work(worker, work, &worker->work_list); + if (!work->canceling) + kthread_insert_work(worker, work, &worker->work_list); raw_spin_unlock_irqrestore(&worker->lock, flags); } |