[PATCH] fs/userfaultfd.c: simplify the calculation of new_flags

From: Wei Yang
Date: Tue Aug 06 2019 - 01:39:40 EST


Finally new_flags equals old vm_flags *OR* vm_flags.

It is not necessary to mask them first.

Signed-off-by: Wei Yang <richardw.yang@xxxxxxxxxxxxxxx>
---
fs/userfaultfd.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index ccbdbd62f0d8..653d8f7c453c 100644
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -1457,7 +1457,7 @@ static int userfaultfd_register(struct userfaultfd_ctx *ctx,
start = vma->vm_start;
vma_end = min(end, vma->vm_end);

- new_flags = (vma->vm_flags & ~vm_flags) | vm_flags;
+ new_flags = vma->vm_flags | vm_flags;
prev = vma_merge(mm, prev, start, vma_end, new_flags,
vma->anon_vma, vma->vm_file, vma->vm_pgoff,
vma_policy(vma),
--
2.17.1