From: Sasha Levin <sasha.levin@oracle.com>
Date: Wed, 10 Dec 2014 23:44:13 +0000 (-0800)
Subject: mm, hugetlb: correct bit shift in hstate_sizelog()
X-Git-Tag: firefly_0821_release~176^2~2734^2~125
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=97ad2be1daf8e6f2d297aa349101b340e1327917;p=firefly-linux-kernel-4.4.55.git

mm, hugetlb: correct bit shift in hstate_sizelog()

hstate_sizelog() would shift left an int rather than long, triggering
undefined behaviour and passing an incorrect value when the requested
page size was more than 4GB, thus breaking >4GB pages.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andrey Ryabinin <a.ryabinin@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 6e6d338641fe..cdd149ca5cc0 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -311,7 +311,8 @@ static inline struct hstate *hstate_sizelog(int page_size_log)
 {
 	if (!page_size_log)
 		return &default_hstate;
-	return size_to_hstate(1 << page_size_log);
+
+	return size_to_hstate(1UL << page_size_log);
 }
 
 static inline struct hstate *hstate_vma(struct vm_area_struct *vma)