[PATCH] memory hotadd fixes: find_next_system_ram catch range fix

find_next_system_ram() is used to find available memory resource at onlining
newly added memory.  This patch fixes following problem.

find_next_system_ram() cannot catch this case.

Resource:      (start)-------------(end)
Section :                (start)-------------(end)

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Keith Mannthey <kmannth@gmail.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/kernel/resource.c b/kernel/resource.c
index 63e879379dbd..46286434af80 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -244,6 +244,7 @@ int find_next_system_ram(struct resource *res)
 
         start = res->start;
         end = res->end;
+        BUG_ON(start >= end);
 
         read_lock(&resource_lock);
         for (p = iomem_resource.child; p ; p = p->sibling) {
@@ -254,7 +255,7 @@ int find_next_system_ram(struct resource *res)
                         p = NULL;
                         break;
                 }
-                if (p->start >= start)
+                if ((p->end >= start) && (p->start < end))
                         break;
         }
         read_unlock(&resource_lock);