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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4CDDCC77B73 for ; Tue, 2 May 2023 14:25:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234458AbjEBOZG (ORCPT ); Tue, 2 May 2023 10:25:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42168 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232885AbjEBOZE (ORCPT ); Tue, 2 May 2023 10:25:04 -0400 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AEEDDE5E; Tue, 2 May 2023 07:25:01 -0700 (PDT) Received: from pps.filterd (m0353728.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 342DbOFC015278; Tue, 2 May 2023 13:40:57 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=5uhTulMAzS5MJZnI8I3gWak2PsaOpEGh5VqMTZIowK4=; b=Ku71v9XWDnZDodXg6j7zdxfKhTydxhO+20aX9ym18IgYV4PsQcVsI0+DVIAo4vbpcvJm jsptSOeo8HgvzAILqJskaDok5xNvqdTb5pUasLDLm9CGhYw++yRuSA9XHSAvdqMuizuk z5oumnKE2HT2C1PIl3dzHJeMhVEe8p/zIeuCw7cgprCUsh+e6f4u9TMcU/I5Quq3uWuA HMtOD7TRyHsp/VSLjvEaHgbYX3EQmrjS+gY7znEJF/CJXeo9JaiEiBRpIT1Nq43hH7Ia cmHGxmQmJL71JZ5dA0K2fKzT/g9gzS8OsXjggmQzjQvqlBcPwyt3GUOK+dOpsabmIP/v fg== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3qb2s3a33n-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 02 May 2023 13:40:56 +0000 Received: from m0353728.ppops.net (m0353728.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 342DbMnK015082; Tue, 2 May 2023 13:39:46 GMT Received: from ppma01wdc.us.ibm.com (fd.55.37a9.ip4.static.sl-reverse.com [169.55.85.253]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3qb2s3a07q-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 02 May 2023 13:39:46 +0000 Received: from pps.filterd (ppma01wdc.us.ibm.com [127.0.0.1]) by ppma01wdc.us.ibm.com (8.17.1.19/8.17.1.19) with ESMTP id 342BZUhc011904; Tue, 2 May 2023 13:38:37 GMT Received: from smtprelay05.wdc07v.mail.ibm.com ([9.208.129.117]) by ppma01wdc.us.ibm.com (PPS) with ESMTPS id 3q8tv7qhcc-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 02 May 2023 13:38:37 +0000 Received: from smtpav06.wdc07v.mail.ibm.com (smtpav06.wdc07v.mail.ibm.com [10.39.53.233]) by smtprelay05.wdc07v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 342DcYIE19268126 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 2 May 2023 13:38:34 GMT Received: from smtpav06.wdc07v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 08C5E5804E; Tue, 2 May 2023 13:38:34 +0000 (GMT) Received: from smtpav06.wdc07v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 655BF5803F; Tue, 2 May 2023 13:38:29 +0000 (GMT) Received: from [9.60.89.243] (unknown [9.60.89.243]) by smtpav06.wdc07v.mail.ibm.com (Postfix) with ESMTP; Tue, 2 May 2023 13:38:29 +0000 (GMT) Message-ID: <18ae04fe-f906-7fce-c560-8268df989c34@linux.ibm.com> Date: Tue, 2 May 2023 09:38:28 -0400 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.10.0 Subject: Re: [PATCH v6 3/3] mm/gup: disallow FOLL_LONGTERM GUP-fast writing to file-backed mappings Content-Language: en-US To: David Hildenbrand , Jason Gunthorpe , Christian Borntraeger Cc: Lorenzo Stoakes , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton , Jens Axboe , Matthew Wilcox , Dennis Dalessandro , Leon Romanovsky , Christian Benvenuti , Nelson Escobar , Bernard Metzler , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Ian Rogers , Adrian Hunter , Bjorn Topel , Magnus Karlsson , Maciej Fijalkowski , Jonathan Lemon , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Christian Brauner , Richard Cochran , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , linux-fsdevel@vger.kernel.org, linux-perf-users@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, Oleg Nesterov , John Hubbard , Jan Kara , "Kirill A . Shutemov" , Pavel Begunkov , Mika Penttila , Dave Chinner , "Theodore Ts'o" , Peter Xu References: <7d56b424-ba79-4b21-b02c-c89705533852@lucifer.local> From: Matthew Rosato In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: cfCath4cF-1F5F4rlea0MEy-pmVYAYwq X-Proofpoint-GUID: zAYM_OqMxiDWZ-V_66ZL0HGVGZw9AHI1 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.254,Aquarius:18.0.942,Hydra:6.0.573,FMLib:17.11.170.22 definitions=2023-05-02_08,2023-04-27_01,2023-02-09_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 impostorscore=0 lowpriorityscore=0 phishscore=0 priorityscore=1501 malwarescore=0 bulkscore=0 suspectscore=0 spamscore=0 clxscore=1011 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2303200000 definitions=main-2305020115 Precedence: bulk List-ID: X-Mailing-List: linux-perf-users@vger.kernel.org On 5/2/23 9:28 AM, David Hildenbrand wrote: > On 02.05.23 15:10, Jason Gunthorpe wrote: >> On Tue, May 02, 2023 at 03:04:27PM +0200, Christian Borntraeger wrote: >> \> > We can reintroduce a flag to permit exceptions if this is really broken, are you >>>> able to test? I don't have an s390 sat around :) >>> >>> Matt (Rosato on cc) probably can. In the end, it would mean having >>>    >>>      >>>    >> >> This s390 code is the least of the problems, after this series VFIO >> won't startup at all with this configuration. > > Good question if the domain would fail to start. I recall that IOMMUs for zPCI are special on s390x. [1] Eh, well what you referenced there never merged. We will eventually do something like this, but via iommufd. But right now s390 is still using vfio type1 iommu > > Well, zPCI is special. I cannot immediately tell when we would trigger long-term pinning. Enabling a zPCI device in a QEMU guest when using zPCI interpretation facilities > > [1] https://www.mail-archive.com/qemu-devel@nongnu.org/msg875728.html >