From 52530f55a22a0448cf9daf6f597a797328d795c7 Mon Sep 17 00:00:00 2001
From: Tejun Heo <tj@kernel.org>
Date: Fri, 2 Jul 2010 10:03:51 +0200
Subject: [PATCH] --- yaml --- r: 206234 b: refs/heads/master c:
 4ce48b37bfedc2bc11e61eae76784887e88b922c h: refs/heads/master v: v3

---
 [refs]                   | 2 +-
 trunk/kernel/workqueue.c | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 25c0bab4303e..f28274c6947b 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: cb444766996395d4370bcc17ec895dd4e13ceb72
+refs/heads/master: 4ce48b37bfedc2bc11e61eae76784887e88b922c
diff --git a/trunk/kernel/workqueue.c b/trunk/kernel/workqueue.c
index 558733801ac0..b59c946433f4 100644
--- a/trunk/kernel/workqueue.c
+++ b/trunk/kernel/workqueue.c
@@ -2138,6 +2138,10 @@ void flush_workqueue(struct workqueue_struct *wq)
 
 	mutex_lock(&wq->flush_mutex);
 
+	/* we might have raced, check again with mutex held */
+	if (wq->first_flusher != &this_flusher)
+		goto out_unlock;
+
 	wq->first_flusher = NULL;
 
 	BUG_ON(!list_empty(&this_flusher.list));