printk: Fix rq->lock vs logbuf_lock unlock lock inversion
dbda92d1 · Bu, Yitian <[email protected]> · 2013-02-18 12:53:37 +00:00
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 <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/E807E903FE6CBE4D95E420FBFCC273B827413C@nasanexd01h.na.qualcomm.com
Signed-off-by: Thomas Gleixner <[email protected]>
- Commit
- dbda92d16f8655044e082930e4e9d244b87fde77
- Parents
- 211b0cdc
Changes
1 files changed · +1 −1
diff --git a/kernel/printk.c b/kernel/printk.c
index 267ce78..e698e80 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -1358,9 +1358,9 @@ static int console_trylock_for_printk(unsigned int cpu)
}
}
logbuf_cpu = UINT_MAX;
+ raw_spin_unlock(&logbuf_lock);
if (wake)
up(&console_sem);
- raw_spin_unlock(&logbuf_lock);
return retval;
}