Patch "printk: Fix rq->lock vs logbuf_lock unlock lock inversion" has been added to the 3.10-stable tree

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This is a note to let you know that I've just added the patch titled

    printk: Fix rq->lock vs logbuf_lock unlock lock inversion

to the 3.10-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     printk-fix-rq-lock-vs-logbuf_lock-unlock-lock-inversion.patch
and it can be found in the queue-3.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.


>From dbda92d16f8655044e082930e4e9d244b87fde77 Mon Sep 17 00:00:00 2001
From: "Bu, Yitian" <ybu@xxxxxxxxxxxxxxxx>
Date: Mon, 18 Feb 2013 12:53:37 +0000
Subject: printk: Fix rq->lock vs logbuf_lock unlock lock inversion

From: "Bu, Yitian" <ybu@xxxxxxxxxxxxxxxx>

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@xxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Link: http://lkml.kernel.org/r/E807E903FE6CBE4D95E420FBFCC273B827413C@xxxxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 kernel/printk.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -1369,9 +1369,9 @@ static int console_trylock_for_printk(un
 		}
 	}
 	logbuf_cpu = UINT_MAX;
+	raw_spin_unlock(&logbuf_lock);
 	if (wake)
 		up(&console_sem);
-	raw_spin_unlock(&logbuf_lock);
 	return retval;
 }
 


Patches currently in stable-queue which might be from ybu@xxxxxxxxxxxxxxxx are

queue-3.10/printk-fix-rq-lock-vs-logbuf_lock-unlock-lock-inversion.patch
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