From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753538AbdBNLBl (ORCPT ); Tue, 14 Feb 2017 06:01:41 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:59217 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752565AbdBNLA3 (ORCPT ); Tue, 14 Feb 2017 06:00:29 -0500 From: Michael Ellerman To: "Aneesh Kumar K.V" , akpm@linux-foundation.org, Rik van Riel , Mel Gorman , paulus@ozlabs.org, benh@kernel.crashing.org Cc: 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. In-Reply-To: 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> User-Agent: Notmuch/0.21 (https://notmuchmail.org) Date: Tue, 14 Feb 2017 21:59:23 +1100 MIME-Version: 1.0 Content-Type: text/plain X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 17021411-1617-0000-0000-000001A7F7F0 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17021411-1618-0000-0000-000047BB2506 Message-Id: <874lzxm41g.fsf@concordia.ellerman.id.au> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-02-14_07:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1612050000 definitions=main-1702140110 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org "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. cheers