X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;f=fs%2Ffs-writeback.c;h=8461a63220398024c2aef5d4795d2f2aadd4ebfa;hb=77e080e7680e1e615587352f70c87b9e98126d03;hp=8aaa7eec7b74a24018795aae91e29781bdbc89ac;hpb=298fb76a5583900a155d387efaf37a8b39e5dea2;p=linux-2.6-block.git

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 8aaa7eec7b74..8461a6322039 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -164,8 +164,13 @@ static void finish_writeback_work(struct bdi_writeback *wb,
 
 	if (work->auto_free)
 		kfree(work);
-	if (done && atomic_dec_and_test(&done->cnt))
-		wake_up_all(done->waitq);
+	if (done) {
+		wait_queue_head_t *waitq = done->waitq;
+
+		/* @done can't be accessed after the following dec */
+		if (atomic_dec_and_test(&done->cnt))
+			wake_up_all(waitq);
+	}
 }
 
 static void wb_queue_work(struct bdi_writeback *wb,
@@ -900,7 +905,7 @@ restart:
  * cgroup_writeback_by_id - initiate cgroup writeback from bdi and memcg IDs
  * @bdi_id: target bdi id
  * @memcg_id: target memcg css id
- * @nr_pages: number of pages to write, 0 for best-effort dirty flushing
+ * @nr: number of pages to write, 0 for best-effort dirty flushing
  * @reason: reason why some writeback work initiated
  * @done: target wb_completion
  *