From: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Date: Mon, 29 Apr 2013 22:07:42 +0000 (-0700)
Subject: mmap: find_vma: remove the WARN_ON_ONCE(!mm) check
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=ee5df0570c8af2610b28ab79bd8f8f8195687773;p=openwrt%2Fstaging%2Fblogic.git

mmap: find_vma: remove the WARN_ON_ONCE(!mm) check

Remove the WARN_ON_ONCE(!mm) check as the comment suggested.  Kernel
code calls find_vma only when it is absolutely sure that the mm_struct
arg to it is non-NULL.

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: k80c <k80ck80c@gmail.com>
Cc: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/mm/mmap.c b/mm/mmap.c
index 0db0de1c2fbe..b2c363f7ae54 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1935,9 +1935,6 @@ struct vm_area_struct *find_vma(struct mm_struct *mm, unsigned long addr)
 {
 	struct vm_area_struct *vma = NULL;
 
-	if (WARN_ON_ONCE(!mm))		/* Remove this in linux-3.6 */
-		return NULL;
-
 	/* Check the cache first. */
 	/* (Cache hit rate is typically around 35%.) */
 	vma = ACCESS_ONCE(mm->mmap_cache);