From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 776A4ECAAD5 for ; Tue, 6 Sep 2022 14:49:10 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4MMSvS7327z3bkP for ; Wed, 7 Sep 2022 00:49:08 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=ibm.com header.i=@ibm.com header.a=rsa-sha256 header.s=pp1 header.b=nCcilSm8; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.ibm.com (client-ip=148.163.156.1; helo=mx0a-001b2d01.pphosted.com; envelope-from=ldufour@linux.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=ibm.com header.i=@ibm.com header.a=rsa-sha256 header.s=pp1 header.b=nCcilSm8; dkim-atps=neutral Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4MMStg5726z2yxQ for ; Wed, 7 Sep 2022 00:48:27 +1000 (AEST) Received: from pps.filterd (m0098410.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 286EaRfD002774; Tue, 6 Sep 2022 14:48:05 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=message-id : date : mime-version : subject : to : cc : references : from : in-reply-to : content-type : content-transfer-encoding; s=pp1; bh=iD2882N/HlldKSEr9X6ZoBibI3jeqzaIEUnBgAl5tZU=; b=nCcilSm8md6OE2sLtootXm+XF8tFvTEcTQ8Z0Mkv85PmeO/AGtlTFGdjSSREbOJt8I3z N2lSHUcS/oq1VKIafJaN5ySuuJeWgGbl1EyYDKh+wNS1D0BiMjsp8+qRDY151LrZ8Fzo c0+j3TQZVIWDu/noBvk9j1VBilzA9T90Salr/P1n18wQ3/Uk0pHenqhnD45Gg5kkq7GO SeJ1cnqOaEnrzt/zILQimERc+AuzH5aE1ocHnwu61J8LtOHX7ShPT4zp3HExg5kNH1EP +xQJXYmITgme9ZGJXcPEQjT8o4Y0j7GWG+MSQyQaW9/akcr6wIudy05DmFj645nFssd1 2A== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3je7rn1ycw-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 06 Sep 2022 14:48:04 +0000 Received: from m0098410.ppops.net (m0098410.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 286EaXRs003410; Tue, 6 Sep 2022 14:48:04 GMT Received: from ppma06ams.nl.ibm.com (66.31.33a9.ip4.static.sl-reverse.com [169.51.49.102]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3je7rn1yb5-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 06 Sep 2022 14:48:03 +0000 Received: from pps.filterd (ppma06ams.nl.ibm.com [127.0.0.1]) by ppma06ams.nl.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 286Ea5OM006187; Tue, 6 Sep 2022 14:48:01 GMT Received: from b06cxnps4076.portsmouth.uk.ibm.com (d06relay13.portsmouth.uk.ibm.com [9.149.109.198]) by ppma06ams.nl.ibm.com with ESMTP id 3jbx6hkwvu-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 06 Sep 2022 14:48:00 +0000 Received: from b06wcsmtp001.portsmouth.uk.ibm.com (b06wcsmtp001.portsmouth.uk.ibm.com [9.149.105.160]) by b06cxnps4076.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 286Elwjj39780718 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 6 Sep 2022 14:47:58 GMT Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 8C6A4A405C; Tue, 6 Sep 2022 14:47:58 +0000 (GMT) Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 69530A4054; Tue, 6 Sep 2022 14:47:57 +0000 (GMT) Received: from [9.101.4.33] (unknown [9.101.4.33]) by b06wcsmtp001.portsmouth.uk.ibm.com (Postfix) with ESMTP; Tue, 6 Sep 2022 14:47:57 +0000 (GMT) Message-ID: <98d5f462-c4dc-a967-0ab0-f24dd3e37dff@linux.ibm.com> Date: Tue, 6 Sep 2022 16:47:57 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0) Gecko/20100101 Thunderbird/102.2.0 Subject: Re: [RFC PATCH RESEND 09/28] mm/mempolicy: mark VMA as locked when changing protection policy Content-Language: fr To: Suren Baghdasaryan , akpm@linux-foundation.org References: <20220901173516.702122-1-surenb@google.com> <20220901173516.702122-10-surenb@google.com> From: Laurent Dufour In-Reply-To: <20220901173516.702122-10-surenb@google.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-GUID: 7I7HaW_zSPCUESol8JKQ6keMsvh5MEMI X-Proofpoint-ORIG-GUID: n0vpG0zoQiPRwb2hnQ9A_0zBzLzp1LaC X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.528,FMLib:17.11.122.1 definitions=2022-09-06_07,2022-09-06_02,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 impostorscore=0 lowpriorityscore=0 mlxscore=0 suspectscore=0 spamscore=0 bulkscore=0 phishscore=0 mlxlogscore=959 malwarescore=0 adultscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2207270000 definitions=main-2209060070 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: michel@lespinasse.org, joelaf@google.com, songliubraving@fb.com, mhocko@suse.com, david@redhat.com, peterz@infradead.org, bigeasy@linutronix.de, peterx@redhat.com, dhowells@redhat.com, linux-mm@kvack.org, jglisse@google.com, dave@stgolabs.net, minchan@google.com, x86@kernel.org, hughd@google.com, willy@infradead.org, laurent.dufour@fr.ibm.com, mgorman@suse.de, rientjes@google.com, axelrasmussen@google.com, kernel-team@android.com, paulmck@kernel.org, liam.howlett@oracle.com, luto@kernel.org, vbabka@suse.cz, linux-arm-kernel@lists.infradead.org, kent.overstreet@linux.dev, linux-kernel@vger.kernel.org, hannes@cmpxchg.org, linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Le 01/09/2022 à 19:34, Suren Baghdasaryan a écrit : > Protect VMA from concurrent page fault handler while performing VMA > protection policy changes. > > Signed-off-by: Suren Baghdasaryan > --- > mm/mempolicy.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/mm/mempolicy.c b/mm/mempolicy.c > index b73d3248d976..6be1e5c75556 100644 > --- a/mm/mempolicy.c > +++ b/mm/mempolicy.c > @@ -383,8 +383,10 @@ void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new) > struct vm_area_struct *vma; > > mmap_write_lock(mm); > - for (vma = mm->mmap; vma; vma = vma->vm_next) > + for (vma = mm->mmap; vma; vma = vma->vm_next) { > + vma_mark_locked(vma); > mpol_rebind_policy(vma->vm_policy, new); > + } > mmap_write_unlock(mm); > } > > @@ -632,6 +634,7 @@ unsigned long change_prot_numa(struct vm_area_struct *vma, > struct mmu_gather tlb; > int nr_updated; > > + vma_mark_locked(vma); If I understand that corretly, the VMA itself is not impacted, only the PMDs/PTEs, and they are protected using the page table locks. Am I missing something? > tlb_gather_mmu(&tlb, vma->vm_mm); > > nr_updated = change_protection(&tlb, vma, addr, end, PAGE_NONE, > @@ -765,6 +768,7 @@ static int vma_replace_policy(struct vm_area_struct *vma, > if (IS_ERR(new)) > return PTR_ERR(new); > > + vma_mark_locked(vma); > if (vma->vm_ops && vma->vm_ops->set_policy) { > err = vma->vm_ops->set_policy(vma, new); > if (err)