From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751305AbdBOAUL (ORCPT ); Tue, 14 Feb 2017 19:20:11 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:59364 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750816AbdBOAUK (ORCPT ); Tue, 14 Feb 2017 19:20:10 -0500 Date: Tue, 14 Feb 2017 16:20:08 -0800 From: Andrew Morton To: Michael Ellerman Cc: "Aneesh Kumar K.V" , Rik van Riel , Mel Gorman , paulus@ozlabs.org, benh@kernel.crashing.org, linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH V2 1/2] mm/autonuma: Let architecture override how the write bit should be stashed in a protnone pte. Message-Id: <20170214162008.bd592c747fc5e167c10ce7b8@linux-foundation.org> In-Reply-To: <874lzxm41g.fsf@concordia.ellerman.id.au> References: <1487050314-3892-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <1487050314-3892-2-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <87poilmien.fsf@concordia.ellerman.id.au> <874lzxm41g.fsf@concordia.ellerman.id.au> X-Mailer: Sylpheed 3.4.1 (GTK+ 2.24.23; 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, 14 Feb 2017 21:59:23 +1100 Michael Ellerman wrote: > "Aneesh Kumar K.V" writes: > > > On Tuesday 14 February 2017 11:19 AM, Michael Ellerman wrote: > >> "Aneesh Kumar K.V" writes: > >> > >>> Autonuma preserves the write permission across numa fault to avoid taking > >>> a writefault after a numa fault (Commit: b191f9b106ea " mm: numa: preserve PTE > >>> write permissions across a NUMA hinting fault"). Architecture can implement > >>> protnone in different ways and some may choose to implement that by clearing Read/ > >>> Write/Exec bit of pte. Setting the write bit on such pte can result in wrong > >>> behaviour. Fix this up by allowing arch to override how to save the write bit > >>> on a protnone pte. > >> This is pretty obviously a nop on arches that don't implement the new > >> hooks, but it'd still be good to get an ack from someone in mm land > >> before I merge it. > > > > > > To get it apply cleanly you may need > > http://ozlabs.org/~akpm/mmots/broken-out/mm-autonuma-dont-use-set_pte_at-when-updating-protnone-ptes.patch > > http://ozlabs.org/~akpm/mmots/broken-out/mm-autonuma-dont-use-set_pte_at-when-updating-protnone-ptes-fix.patch > > Ah OK, I missed those. > > In that case these two should probably go via Andrew's tree. Done. But mm-autonuma-dont-use-set_pte_at-when-updating-protnone-ptes.patch is on hold because Aneesh saw a testing issue, so these two are also on hold.