Commit 7d2a354861e9257824a201d39a11e6a4d2a60cb4
Committed by
Greg Kroah-Hartman
1 parent
b087b8b11e
Exists in
smarct4x-processor-sdk-04.01.00.06
and in
1 other branch
NFSv4.1: Fix a race where CB_NOTIFY_LOCK fails to wake a waiter
commit b7dbcc0e433f0f61acb89ed9861ec996be4f2b38 upstream. nfs4_retry_setlk() sets the task's state to TASK_INTERRUPTIBLE within the same region protected by the wait_queue's lock after checking for a notification from CB_NOTIFY_LOCK callback. However, after releasing that lock, a wakeup for that task may race in before the call to freezable_schedule_timeout_interruptible() and set TASK_WAKING, then freezable_schedule_timeout_interruptible() will set the state back to TASK_INTERRUPTIBLE before the task will sleep. The result is that the task will sleep for the entire duration of the timeout. Since we've already set TASK_INTERRUPTIBLE in the locked section, just use freezable_schedule_timout() instead. Fixes: a1d617d8f134 ("nfs: allow blocking locks to be awoken by lock callbacks") Signed-off-by: Benjamin Coddington <bcodding@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Showing 1 changed file with 1 additions and 1 deletions Side-by-side Diff
fs/nfs/nfs4proc.c
... | ... | @@ -6419,7 +6419,7 @@ |
6419 | 6419 | set_current_state(TASK_INTERRUPTIBLE); |
6420 | 6420 | spin_unlock_irqrestore(&q->lock, flags); |
6421 | 6421 | |
6422 | - freezable_schedule_timeout_interruptible(NFS4_LOCK_MAXTIMEOUT); | |
6422 | + freezable_schedule_timeout(NFS4_LOCK_MAXTIMEOUT); | |
6423 | 6423 | } |
6424 | 6424 | |
6425 | 6425 | finish_wait(q, &wait); |