---

yaml --- r: 222872 b: refs/heads/master c: a0b0f58 h: refs/heads/master v: v3
git-mirror · Dec 2, 2010 · 6ab030c · 6ab030c
1 parent 0672422
commit 6ab030c
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Showing 2 changed files with 7 additions and 2 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 20d6c96b5f1cad5c5da4641945ec17a1d9a1afc8
+refs/heads/master: a0b0f58cdd32ab363a600a294ddaa90f0c32de8c
diff --git a/trunk/mm/ksm.c b/trunk/mm/ksm.c
@@ -1724,8 +1724,13 @@ static int ksm_memory_callback(struct notifier_block *self,
 		/*
 		 * Keep it very simple for now: just lock out ksmd and
 		 * MADV_UNMERGEABLE while any memory is going offline.
+		 * mutex_lock_nested() is necessary because lockdep was alarmed
+		 * that here we take ksm_thread_mutex inside notifier chain
+		 * mutex, and later take notifier chain mutex inside
+		 * ksm_thread_mutex to unlock it.   But that's safe because both
+		 * are inside mem_hotplug_mutex.
 		 */
-		mutex_lock(&ksm_thread_mutex);
+		mutex_lock_nested(&ksm_thread_mutex, SINGLE_DEPTH_NESTING);
 		break;
 
 	case MEM_OFFLINE: