From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752018AbaHWWUT (ORCPT ); Sat, 23 Aug 2014 18:20:19 -0400 Received: from mail-qc0-f202.google.com ([209.85.216.202]:45236 "EHLO mail-qc0-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751213AbaHWWUS (ORCPT ); Sat, 23 Aug 2014 18:20:18 -0400 From: Peter Feiner To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Peter Feiner , "Kirill A. Shutemov" , Cyrill Gorcunov , Pavel Emelyanov , Jamie Liu , Hugh Dickins , Naoya Horiguchi , Andrew Morton Subject: [PATCH v2 2/3] mm: mprotect: preserve special page protection bits Date: Sat, 23 Aug 2014 18:12:00 -0400 Message-Id: <1408831921-10168-3-git-send-email-pfeiner@google.com> X-Mailer: git-send-email 2.1.0.rc2.206.gedb03e5 In-Reply-To: <1408831921-10168-1-git-send-email-pfeiner@google.com> References: <1408571182-28750-1-git-send-email-pfeiner@google.com> <1408831921-10168-1-git-send-email-pfeiner@google.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We don't want to zap special page protection bits on mprotect. Analogous to the bug fixed in c9d0bf241451a3ab7d02e1652c22b80cd7d93e8f where vm_page_prot bits set by drivers were zapped when write notifications were enabled on new VMAs. Signed-off-by: Peter Feiner --- mm/mprotect.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/mprotect.c b/mm/mprotect.c index c43d557..1c1afd4 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -324,7 +324,7 @@ success: vm_get_page_prot(newflags)); if (vma_wants_writenotify(vma)) { - vma->vm_page_prot = vm_get_page_prot(newflags & ~VM_SHARED); + vma_enable_writenotify(vma); dirty_accountable = 1; } -- 2.1.0.rc2.206.gedb03e5