From: Oleg Nesterov <oleg@tv-sign.ru>

Add might_sleep() checks to flush_xxx() functions.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/workqueue.c |    4 ++++
 1 files changed, 4 insertions(+)

diff -puN kernel/workqueue.c~workqueue-dont-save-interrupts-in-run_workqueue-update-2 kernel/workqueue.c
--- a/kernel/workqueue.c~workqueue-dont-save-interrupts-in-run_workqueue-update-2
+++ a/kernel/workqueue.c
@@ -393,6 +393,8 @@ static void flush_cpu_workqueue(struct c
  */
 void fastcall flush_workqueue(struct workqueue_struct *wq)
 {
+	might_sleep();
+
 	if (is_single_threaded(wq))
 		flush_cpu_workqueue(per_cpu_ptr(wq->cpu_wq, singlethread_cpu));
 	else {
@@ -439,6 +441,8 @@ void flush_work(struct workqueue_struct 
 {
 	struct cpu_workqueue_struct *cwq;
 
+	might_sleep();
+
 	cwq = get_wq_data(work);
 	/* Was it ever queued ? */
 	if (!cwq)
_