diff options
author | Bu, Yitian <ybu@qti.qualcomm.com> | 2013-02-18 07:53:37 -0500 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-07-25 17:07:31 -0400 |
commit | 5df5df87f2b5f5d75825207d61a272b168d8cab6 (patch) | |
tree | 9909ae74a18000317fd1e4889fd9e67b36376442 /kernel | |
parent | bcaef288b2a3187de17220e86e15b762b3b0808e (diff) |
printk: Fix rq->lock vs logbuf_lock unlock lock inversion
commit dbda92d16f8655044e082930e4e9d244b87fde77 upstream.
commit 07354eb1a74d1 ("locking printk: Annotate logbuf_lock as raw")
reintroduced a lock inversion problem which was fixed in commit
0b5e1c5255 ("printk: Release console_sem after logbuf_lock"). This
happened probably when fixing up patch rejects.
Restore the ordering and unlock logbuf_lock before releasing
console_sem.
Signed-off-by: ybu <ybu@qti.qualcomm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/E807E903FE6CBE4D95E420FBFCC273B827413C@nasanexd01h.na.qualcomm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/printk.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/printk.c b/kernel/printk.c index 8212c1aef125..d37d45c90ae6 100644 --- a/kernel/printk.c +++ b/kernel/printk.c | |||
@@ -1369,9 +1369,9 @@ static int console_trylock_for_printk(unsigned int cpu) | |||
1369 | } | 1369 | } |
1370 | } | 1370 | } |
1371 | logbuf_cpu = UINT_MAX; | 1371 | logbuf_cpu = UINT_MAX; |
1372 | raw_spin_unlock(&logbuf_lock); | ||
1372 | if (wake) | 1373 | if (wake) |
1373 | up(&console_sem); | 1374 | up(&console_sem); |
1374 | raw_spin_unlock(&logbuf_lock); | ||
1375 | return retval; | 1375 | return retval; |
1376 | } | 1376 | } |
1377 | 1377 | ||