From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752130AbaIYHNK (ORCPT ); Thu, 25 Sep 2014 03:13:10 -0400 Received: from mail-la0-f53.google.com ([209.85.215.53]:53472 "EHLO mail-la0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751753AbaIYHNJ (ORCPT ); Thu, 25 Sep 2014 03:13:09 -0400 Date: Thu, 25 Sep 2014 10:30:06 +0400 From: Cyrill Gorcunov To: Andrew Morton Cc: Peter Feiner , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Pavel Emelyanov , Jamie Liu , Hugh Dickins Subject: Re: [PATCH] mm: softdirty: keep bit when zapping file pte Message-ID: <20140925063006.GN2227@moon> References: <1411200187-40896-1-git-send-email-pfeiner@google.com> <20140924145927.04e8eb7ba6c1410a797293c7@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140924145927.04e8eb7ba6c1410a797293c7@linux-foundation.org> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 24, 2014 at 02:59:27PM -0700, Andrew Morton wrote: > On Sat, 20 Sep 2014 01:03:07 -0700 Peter Feiner wrote: > > > Fixes the same bug as b43790eedd31e9535b89bbfa45793919e9504c34 and > > 9aed8614af5a05cdaa32a0b78b0f1a424754a958 where the return value of > > pte_*mksoft_dirty was being ignored. > > > > To be sure that no other pte/pmd "mk" function return values were > > being ignored, I annotated the functions in > > arch/x86/include/asm/pgtable.h with __must_check and rebuilt. > > > > Grumble. > > It is useful to identify preceding similar patches but that isn't a > good way of describing *this* patch. What is wrong with the current > code, how does the patch fix it. The userspace effect is that without this patch softdirty mark might be lost if file mapped pte get zapped. It should go into @stable series after 3.12. > > And, particularly, what do you think are the end-user visible effects > of the bug? This info helps people to work out which kernel versions > need the fix.