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| author |   Maxime Ripard <maxime@cerno.tech> | 2020-08-18 14:14:25 +0200 |
|---|---|---|
| committer | Maxime Ripard <maxime@cerno.tech> | 2020-08-18 14:14:25 +0200 |
| commit | d85ddd1318e66c0c2665dbfcbc21a8b66c9152aa (patch) | |
| tree | e49e401abd2468b398d4bc84c7e05c2c2c3b0966 /kernel/task_work.c | |
| parent | MAINTAINERS: Change maintainer for hisilicon DRM driver (diff) | |
| parent | Linux 5.9-rc1 (diff) | |
| download | wireguard-linux-d85ddd1318e66c0c2665dbfcbc21a8b66c9152aa.tar.xz wireguard-linux-d85ddd1318e66c0c2665dbfcbc21a8b66c9152aa.zip | |
Merge v5.9-rc1 into drm-misc-next
Sam needs 5.9-rc1 to have dev_err_probe in to merge some patches.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Diffstat (limited to 'kernel/task_work.c')
| -rw-r--r-- | kernel/task_work.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/kernel/task_work.c b/kernel/task_work.c index 5c0848ca1287..613b2d634af8 100644 --- a/kernel/task_work.c +++ b/kernel/task_work.c @@ -42,7 +42,13 @@ task_work_add(struct task_struct *task, struct callback_head *work, int notify) set_notify_resume(task); break; case TWA_SIGNAL: - if (lock_task_sighand(task, &flags)) { + /* + * Only grab the sighand lock if we don't already have some + * task_work pending. This pairs with the smp_store_mb() + * in get_signal(), see comment there. + */ + if (!(READ_ONCE(task->jobctl) & JOBCTL_TASK_WORK) && + lock_task_sighand(task, &flags)) { task->jobctl |= JOBCTL_TASK_WORK; signal_wake_up(task, 0); unlock_task_sighand(task, &flags); |