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From:   Wei Yang <richardw.yang@linux.intel.com>
To:     linux-kernel@vger.kernel.org
Cc:     viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org,
        Wei Yang <richardw.yang@linux.intel.com>
Subject: [PATCH] fs/userfaultfd.c: simplify the calculation of new_flags
Date:   Tue,  6 Aug 2019 13:38:59 +0800
Message-Id: <20190806053859.2374-1-richardw.yang@linux.intel.com>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

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@linux.intel.com>
---
 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