commit 2b37c35e6552b0d04d5db9728bc7af22d53f731a
author Becky Bruce <beckyb@kernel.crashing.org> Mon Jul 25 17:11:49 2011 -0700
committer Linus Torvalds <torvalds@linux-foundation.org> Mon Jul 25 20:57:07 2011 -0700
tree 5ccccfe90e6bfb472e6000fd4f55c9be66eb795c
parent d694ad62bf539dbb20a0899ac2a954555f9e4a83

fs/hugetlbfs/inode.c: fix pgoff alignment checking on 32-bit

This:

    vma->vm_pgoff & ~(huge_page_mask(h) >> PAGE_SHIFT)

is incorrect on 32-bit.  It causes us to & the pgoff with something that
looks like this (for a 4m hugepage): 0xfff003ff.  The mask should be
flipped and *then* shifted, to give you 0x0000_03fff.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/hugetlbfs/inode.c

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 7aafeb8..537a209 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -94,7 +94,7 @@
 	vma->vm_flags |= VM_HUGETLB | VM_RESERVED;
 	vma->vm_ops = &hugetlb_vm_ops;
 
-	if (vma->vm_pgoff & ~(huge_page_mask(h) >> PAGE_SHIFT))
+	if (vma->vm_pgoff & (~huge_page_mask(h) >> PAGE_SHIFT))
 		return -EINVAL;
 
 	vma_len = (loff_t)(vma->vm_end - vma->vm_start);