mmap: find_vma: remove the WARN_ON_ONCE(!mm) check
authorZhang Yanfei <zhangyanfei@cn.fujitsu.com>
Mon, 29 Apr 2013 22:07:42 +0000 (15:07 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Mon, 29 Apr 2013 22:54:34 +0000 (15:54 -0700)
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>
mm/mmap.c

index 0db0de1c2fbee21e0e9919af66021b190d789731..b2c363f7ae54391c388a70112752173641edf6c7 100644 (file)
--- 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);