kernel/resource.c: handle reinsertion of an already-inserted resource

If the same resource is inserted to the resource tree (maybe not on purpose), a dead loop will be created. In this situation, The kernel does not report any warning or error :( The command below will show a endless print. #cat /proc/iomem [[email protected]: add WARN_ON()] Signed-off-by: Huang Shijie <[email protected]> Cc: Jesse Barnes <[email protected]> Cc: Bjorn Helgaas <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
niw · Oct 28, 2010 · 5de1cb2 · 5de1cb2
1 parent 144ecf3
commit 5de1cb2
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/kernel/resource.c b/kernel/resource.c
@@ -453,6 +453,8 @@ static struct resource * __insert_resource(struct resource *parent, struct resou
 
 		if (first == parent)
 			return first;
+		if (WARN_ON(first == new))	/* duplicated insertion */
+			return first;
 
 		if ((first->start > new->start) || (first->end < new->end))
 			break;