watchdog: fix double lock in watchdog_nmi_enable_all

Commit ab992dc38f9a ("watchdog: Fix merge 'conflict'") has introduced an
obvious deadlock because of a typo.  watchdog_proc_mutex should be
unlocked on exit.

Thanks to Miroslav Benes who was staring at the code with me and noticed
this.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Duh-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 506edcc500c422b0e40eed1a35a2d2a39360a3e8..581a68a04c64089b847d3b76d1abc138a83bb209 100644 (file)
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -621,7 +621,7 @@ void watchdog_nmi_enable_all(void)
        put_online_cpus();
 
 unlock:
-       mutex_lock(&watchdog_proc_mutex);
+       mutex_unlock(&watchdog_proc_mutex);
 }
 
 void watchdog_nmi_disable_all(void)