From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754396AbeDCXpZ (ORCPT ); Tue, 3 Apr 2018 19:45:25 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:37436 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753685AbeDCXpY (ORCPT ); Tue, 3 Apr 2018 19:45:24 -0400 Date: Tue, 3 Apr 2018 16:45:22 -0700 From: Andrew Morton To: Jerome Glisse Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Ralph Campbell Subject: Re: [PATCH] mm/migrate: properly preserve write attribute in special migrate entry Message-Id: <20180403164522.657185a44e8ada1b741f0a9e@linux-foundation.org> In-Reply-To: <20180403230336.GH5935@redhat.com> References: <20180402023506.12180-1-jglisse@redhat.com> <20180403153046.88cae4ab18646e8e23a648ce@linux-foundation.org> <20180403230336.GH5935@redhat.com> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 3 Apr 2018 19:03:36 -0400 Jerome Glisse wrote: > > That sounds a bit serious. Was a -stable backport considered? > > Like discuss previously with Michal, for lack of upstream user yet > (and PowerPC users of this code are not upstream either yet AFAIK). > > Once i get HMM inside nouveau upstream, i will evaluate if people > wants all fixes to be back ported to stable. > > Finaly this one isn't too bad, it just burn CPU cycles by forcing > CPU to take a second fault on write access ie double fault the same > address. There is no corruption or incorrect states (it behave as > a COWed page from a fork with a mapcount of 1). OK, I updated the changelog with this info. > Do you still want me to be more aggressive with stable backport ? > I don't mind either way. I expect to get HMM nouveau upstream over > next couple release cycle. I guess that doing a single, better-organized cherrypick at a suitable time in the future is a good approach. You might want to discuss this plan with Greg before committing too far.