From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f71.google.com (mail-pg0-f71.google.com [74.125.83.71]) by kanga.kvack.org (Postfix) with ESMTP id CDF056B0008 for ; Thu, 31 May 2018 09:56:09 -0400 (EDT) Received: by mail-pg0-f71.google.com with SMTP id o19-v6so3336816pgn.14 for ; Thu, 31 May 2018 06:56:09 -0700 (PDT) Received: from mga18.intel.com (mga18.intel.com. [134.134.136.126]) by mx.google.com with ESMTPS id c10-v6si17914027plz.190.2018.05.31.06.56.08 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 31 May 2018 06:56:08 -0700 (PDT) From: "Kirill A. Shutemov" Subject: [PATCH] mm/shmem: Zero out unused vma fields in shmem_pseudo_vma_init() Date: Thu, 31 May 2018 16:56:02 +0300 Message-Id: <20180531135602.20321-1-kirill.shutemov@linux.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Hugh Dickins , linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" shmem/tmpfs uses pseudo vma to allocate page with correct NUMA policy. The pseudo vma doesn't have vm_page_prot set. We are going to encode encryption KeyID in vm_page_prot. Having garbage there causes problems. Zero out all unused fields in the pseudo vma. Signed-off-by: Kirill A. Shutemov --- mm/shmem.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/mm/shmem.c b/mm/shmem.c index 9d6c7e595415..693fb82b4b42 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1404,10 +1404,9 @@ static void shmem_pseudo_vma_init(struct vm_area_struct *vma, struct shmem_inode_info *info, pgoff_t index) { /* Create a pseudo vma that just contains the policy */ - vma->vm_start = 0; + memset(vma, 0, sizeof(*vma)); /* Bias interleave by inode number to distribute better across nodes */ vma->vm_pgoff = index + info->vfs_inode.i_ino; - vma->vm_ops = NULL; vma->vm_policy = mpol_shared_policy_lookup(&info->policy, index); } -- 2.17.0