X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=mm%2Fmemory-failure.c;h=44c6bd201d3a1cac7120527b45e2a86f5f77abff;hb=2f39691f31a22e0c6d82573d91306059f8ef920c;hp=a013bc94ebbed4af3764e396b087475310ed5185;hpb=049711bf3cc59501ebeae621aa22acd3918ebd79;p=firefly-linux-kernel-4.4.55.git

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index a013bc94ebbe..44c6bd201d3a 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -1172,6 +1172,16 @@ int memory_failure(unsigned long pfn, int trapno, int flags)
 
 	lock_page(hpage);
 
+	/*
+	 * The page could have changed compound pages during the locking.
+	 * If this happens just bail out.
+	 */
+	if (compound_head(p) != hpage) {
+		action_result(pfn, "different compound page after locking", IGNORED);
+		res = -EBUSY;
+		goto out;
+	}
+
 	/*
 	 * We use page flags to determine what action should be taken, but
 	 * the flags can be modified by the error containment action.  One