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| author | Tejun Heo <[email protected]> | 2011-06-09 18:43:59 +0000 |
|---|---|---|
| committer | Jens Axboe <[email protected]> | 2011-06-09 18:43:59 +0000 |
| commit | fdd514e16bb2531c0c61ae8a1f87740ce217f630 (patch) | |
| tree | 5d7b6d4f9112b0b6f93f7ce939045fb634abc3fa /net/tipc/msg.c | |
| parent | block: remove non-syncing __disk_block_events() and fold it into disk_block_e... (diff) | |
| download | kernel-fdd514e16bb2531c0c61ae8a1f87740ce217f630.tar.gz kernel-fdd514e16bb2531c0c61ae8a1f87740ce217f630.zip | |
block: make disk_block_events() properly wait for work cancellation
disk_block_events() should guarantee that the event work is not in
flight on return and once blocked it shouldn't issue further
cancellations.
Because there was no synchronization between the first blocker doing
cancel_delayed_work_sync() and the following blockers, the following
blockers could finish before cancellation was complete, which broke
both guarantees - event work could be in flight and cancellation could
happen after return.
This bug triggered WARN_ON_ONCE() in disk_clear_events() reported in
bug#34662.
https://bugzilla.kernel.org/show_bug.cgi?id=34662
Fix it by adding an outer mutex which protects both block count
manipulation and work cancellation.
-v2: Use outer mutex instead of bit waitqueue per Linus.
Signed-off-by: Tejun Heo <[email protected]>
Tested-by: Sitsofe Wheeler <[email protected]>
Reported-by: Sitsofe Wheeler <[email protected]>
Reported-by: Borislav Petkov <[email protected]>
Reported-by: Meelis Roos <[email protected]>
Reported-by: Linus Torvalds <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Jens Axboe <[email protected]>
Cc: Kay Sievers <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
Diffstat (limited to 'net/tipc/msg.c')
0 files changed, 0 insertions, 0 deletions