+ kernel-resourcec-handle-reinsertion-of-an-already-inserted-resource.patch added to -mm tree

[akpm@linux-foundation.org]

The patch titled
     kernel/resource.c: handle reinsertion of an already-inserted resource
has been added to the -mm tree.  Its filename is
     kernel-resourcec-handle-reinsertion-of-an-already-inserted-resource.patch

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------------------------------------------------------
Subject: kernel/resource.c: handle reinsertion of an already-inserted resource
From: Huang Shijie <shijie8@gmail.com>

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

[akpm@linux-foundation.org: add WARN_ON()]
Signed-off-by: Huang Shijie <shijie8@gmail.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/resource.c |    2 ++
 1 file changed, 2 insertions(+)

diff -puN kernel/resource.c~kernel-resourcec-handle-reinsertion-of-an-already-inserted-resource kernel/resource.c
--- a/kernel/resource.c~kernel-resourcec-handle-reinsertion-of-an-already-inserted-resource
+++ a/kernel/resource.c
@@ -453,6 +453,8 @@ static struct resource * __insert_resour
 
 		if (first == parent)
 			return first;
+		if (WARN_ON(first == new))	/* duplicated insertion */
+			return first;
 
 		if ((first->start > new->start) || (first->end < new->end))
 			break;
_

Patches currently in -mm which might be from shijie8@gmail.com are

kernel-resourcec-handle-reinsertion-of-an-already-inserted-resource.patch