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author | Xie Yongji <xieyongji@baidu.com> | 2018-11-29 20:50:30 +0800 |
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committer | Ingo Molnar <mingo@kernel.org> | 2019-01-21 11:15:39 +0100 |
commit | e158488be27b157802753a59b336142dc0eb0380 (patch) | |
tree | db577b6083e0b46684933933690abd3f9c034bc2 /kernel/kmod.c | |
parent | b061c38bef43406df8e73c5be06cbfacad5ee6ad (diff) | |
download | linux-e158488be27b157802753a59b336142dc0eb0380.tar.bz2 |
locking/rwsem: Fix (possible) missed wakeup
Because wake_q_add() can imply an immediate wakeup (cmpxchg failure
case), we must not rely on the wakeup being delayed. However, commit:
e38513905eea ("locking/rwsem: Rework zeroing reader waiter->task")
relies on exactly that behaviour in that the wakeup must not happen
until after we clear waiter->task.
[ peterz: Added changelog. ]
Signed-off-by: Xie Yongji <xieyongji@baidu.com>
Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: e38513905eea ("locking/rwsem: Rework zeroing reader waiter->task")
Link: https://lkml.kernel.org/r/1543495830-2644-1-git-send-email-xieyongji@baidu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/kmod.c')
0 files changed, 0 insertions, 0 deletions