From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f199.google.com (mail-pf0-f199.google.com [209.85.192.199]) by kanga.kvack.org (Postfix) with ESMTP id 05E4A6B000A for ; Tue, 20 Mar 2018 17:32:21 -0400 (EDT) Received: by mail-pf0-f199.google.com with SMTP id n15so1623945pff.14 for ; Tue, 20 Mar 2018 14:32:20 -0700 (PDT) Received: from out30-130.freemail.mail.aliyun.com (out30-130.freemail.mail.aliyun.com. [115.124.30.130]) by mx.google.com with ESMTPS id h125si1923642pfc.133.2018.03.20.14.32.19 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 20 Mar 2018 14:32:19 -0700 (PDT) From: Yang Shi Subject: [RFC PATCH 5/8] ipc: shm: pass atomic parameter to do_munmap() Date: Wed, 21 Mar 2018 05:31:23 +0800 Message-Id: <1521581486-99134-6-git-send-email-yang.shi@linux.alibaba.com> In-Reply-To: <1521581486-99134-1-git-send-email-yang.shi@linux.alibaba.com> References: <1521581486-99134-1-git-send-email-yang.shi@linux.alibaba.com> Sender: owner-linux-mm@kvack.org List-ID: To: akpm@linux-foundation.org Cc: yang.shi@linux.alibaba.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org It looks safe to do unlock/relock mmap_sem in the middle of shmat(), so passing "false" here. Signed-off-by: Yang Shi --- ipc/shm.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/ipc/shm.c b/ipc/shm.c index 4643865..1617523 100644 --- a/ipc/shm.c +++ b/ipc/shm.c @@ -1537,7 +1537,8 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, */ file = vma->vm_file; size = i_size_read(file_inode(vma->vm_file)); - do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start, NULL); + do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start, + NULL, false); /* * We discovered the size of the shm segment, so * break out of here and fall through to the next @@ -1564,7 +1565,8 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, if ((vma->vm_ops == &shm_vm_ops) && ((vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff) && (vma->vm_file == file)) - do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start, NULL); + do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start, + NULL, false); vma = next; } @@ -1573,7 +1575,8 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, * given */ if (vma && vma->vm_start == addr && vma->vm_ops == &shm_vm_ops) { - do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start, NULL); + do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start, + NULL, false); retval = 0; } -- 1.8.3.1