From: john stultz <johnstul@us.ibm.com>

Avoid futex_unlock_pi returning -EFAULT (which results in deadlock), by
clearing uval before jumping to retry_locked.

Signed-off-by: John Stultz <johnstul@us.ibm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/futex.c |    1 +
 1 files changed, 1 insertion(+)

diff -puN kernel/futex.c~futex_unlock_pi-hurts-my-brain-and-may-cause kernel/futex.c
--- a/kernel/futex.c~futex_unlock_pi-hurts-my-brain-and-may-cause
+++ a/kernel/futex.c
@@ -1670,6 +1670,7 @@ pi_faulted:
 					 attempt);
 		if (ret)
 			goto out;
+		uval = 0;
 		goto retry_unlocked;
 	}
 
_