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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 28834CD98CC for ; Thu, 11 Jun 2026 13:20:18 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 5F6D66B0095; Thu, 11 Jun 2026 09:20:17 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 5CE7E6B0099; Thu, 11 Jun 2026 09:20:17 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4BCDB6B009B; Thu, 11 Jun 2026 09:20:17 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 396706B0095 for ; Thu, 11 Jun 2026 09:20:17 -0400 (EDT) Received: from smtpin08.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay06.hostedemail.com (Postfix) with ESMTP id CE17F1C35FC for ; Thu, 11 Jun 2026 13:20:16 +0000 (UTC) X-FDA: 84867690432.08.437429A Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf27.hostedemail.com (Postfix) with ESMTP id 136854001C for ; Thu, 11 Jun 2026 13:20:14 +0000 (UTC) Authentication-Results: imf27.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=mZmXI4TC; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf27.hostedemail.com: domain of david@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=david@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1781184015; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=DbAs11x6sdjRPCa1WwOoOtiOTXFWzk8XHr9nWsO7jas=; b=nZQJ1hQd8P6JA8Fih8eKPvVwTu2gHaX/cO6Lb+pC4ZDU+EvM08kh8dcg/PPVpXlCcHz0qr apXC+gGk5shrsO2Y9MXVmmkz0/punqgUZttC37Jhlkcv6Am9zT+3ppJOpWkmNgJY5Ko6Gt XhyoLZTAHfC7tHOZWyZhACcGUQkqxj8= ARC-Authentication-Results: i=1; imf27.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=mZmXI4TC; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf27.hostedemail.com: domain of david@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=david@kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1781184015; b=0JOx4oBS0KvY/sQo4lwX87mln+GxJNwktIRhOWxrGht40Rp/ephn9tOnEYstQFJe158zW3 jmzIc5BlKlhew5KqPb9H6v05NcX4Mr1BANRQTCSSp71tP75HQrjjZ0mjpWxMFQfDZ2ODSg Xl0doyfJoBwlvqDcILbmuxlgnLRWouM= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 685FA6001A; Thu, 11 Jun 2026 13:20:14 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 53A371F00893; Thu, 11 Jun 2026 13:20:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1781184014; bh=DbAs11x6sdjRPCa1WwOoOtiOTXFWzk8XHr9nWsO7jas=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=mZmXI4TCsyxa4sX5pM4DsRByQaaOs3d7C8Ljua/wvAKN9TPmcu2iaMcw9mgsddKo8 dJ4w1P/oR1cXj+hgY/Ibtz3BqRn0ClHXphR+0hydZmdlRauhCf1o1OJ7ODS5JywLgl 0vBVbGss6G3iP07870uUkV8E7U/nHrA/mbl+/7DrGlnxkgh/pwwLTjU35X8ci/C7MN KGxWrMnh2F5orJmyEBmsIhFS0coXBk5XYZD5Q01TrNkodmYflZXuratoNjUAKLgqfC aJTurNg7u2noGQsvfpB4MqpiRz0KI3NtZuWgHcDcG7aE2f3zQUB+W68+dmVZQvlYd/ B6Kwbc72AqZRw== Message-ID: Date: Thu, 11 Jun 2026 15:20:02 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH splitout] mm: memory-failure: serialize TestSetPageHWPoison with zone->lock To: Miaohe Lin , "Michael S. Tsirkin" Cc: Zi Yan , Andrew Morton , linux-kernel@vger.kernel.org, Jason Wang , Xuan Zhuo , =?UTF-8?Q?Eugenio_P=C3=A9rez?= , Muchun Song , Oscar Salvador , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Johannes Weiner , Baolin Wang , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Hugh Dickins , Matthew Brost , Joshua Hahn , Rakie Kim , Byungchul Park , Gregory Price , Ying Huang , Alistair Popple , Christoph Lameter , David Rientjes , Roman Gushchin , Harry Yoo , Axel Rasmussen , Yuanchu Xie , Wei Xu , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Baoquan He , virtualization@lists.linux.dev, linux-mm@kvack.org, Andrea Arcangeli , Naoya Horiguchi References: <20260609111020.e88f51a7b6ebc37360d66fdc@linux-foundation.org> <8c1f468e-b50a-487a-a267-8d1ea5a61c87@kernel.org> <38C84F23-E881-4DB2-86BA-93F39D44AE1B@nvidia.com> <20260609162437-mutt-send-email-mst@kernel.org> <4BA276D9-9EB9-4E2A-8A05-657ACACFF227@nvidia.com> <20260609165829-mutt-send-email-mst@kernel.org> <20260610171646-mutt-send-email-mst@kernel.org> <14537566-94d9-eac5-2636-35f925a9d159@huawei.com> <20260611013644-mutt-send-email-mst@kernel.org> <1b5676ab-0dc5-ef33-9d79-a2bd6090a62d@huawei.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzS5EYXZpZCBIaWxk ZW5icmFuZCAoQ3VycmVudCkgPGRhdmlkQGtlcm5lbC5vcmc+wsGQBBMBCAA6AhsDBQkmWAik AgsJBBUKCQgCFgICHgUCF4AWIQQb2cqtc1xMOkYN/MpN3hD3AP+DWgUCaYJt/AIZAQAKCRBN 3hD3AP+DWriiD/9BLGEKG+N8L2AXhikJg6YmXom9ytRwPqDgpHpVg2xdhopoWdMRXjzOrIKD g4LSnFaKneQD0hZhoArEeamG5tyo32xoRsPwkbpIzL0OKSZ8G6mVbFGpjmyDLQCAxteXCLXz ZI0VbsuJKelYnKcXWOIndOrNRvE5eoOfTt2XfBnAapxMYY2IsV+qaUXlO63GgfIOg8RBaj7x 3NxkI3rV0SHhI4GU9K6jCvGghxeS1QX6L/XI9mfAYaIwGy5B68kF26piAVYv/QZDEVIpo3t7 /fjSpxKT8plJH6rhhR0epy8dWRHk3qT5tk2P85twasdloWtkMZ7FsCJRKWscm1BLpsDn6EQ4 jeMHECiY9kGKKi8dQpv3FRyo2QApZ49NNDbwcR0ZndK0XFo15iH708H5Qja/8TuXCwnPWAcJ DQoNIDFyaxe26Rx3ZwUkRALa3iPcVjE0//TrQ4KnFf+lMBSrS33xDDBfevW9+Dk6IISmDH1R HFq2jpkN+FX/PE8eVhV68B2DsAPZ5rUwyCKUXPTJ/irrCCmAAb5Jpv11S7hUSpqtM/6oVESC 3z/7CzrVtRODzLtNgV4r5EI+wAv/3PgJLlMwgJM90Fb3CB2IgbxhjvmB1WNdvXACVydx55V7 LPPKodSTF29rlnQAf9HLgCphuuSrrPn5VQDaYZl4N/7zc2wcWM7BTQRVy5+RARAA59fefSDR 9nMGCb9LbMX+TFAoIQo/wgP5XPyzLYakO+94GrgfZjfhdaxPXMsl2+o8jhp/hlIzG56taNdt VZtPp3ih1AgbR8rHgXw1xwOpuAd5lE1qNd54ndHuADO9a9A0vPimIes78Hi1/yy+ZEEvRkHk /kDa6F3AtTc1m4rbbOk2fiKzzsE9YXweFjQvl9p+AMw6qd/iC4lUk9g0+FQXNdRs+o4o6Qvy iOQJfGQ4UcBuOy1IrkJrd8qq5jet1fcM2j4QvsW8CLDWZS1L7kZ5gT5EycMKxUWb8LuRjxzZ 3QY1aQH2kkzn6acigU3HLtgFyV1gBNV44ehjgvJpRY2cC8VhanTx0dZ9mj1YKIky5N+C0f21 zvntBqcxV0+3p8MrxRRcgEtDZNav+xAoT3G0W4SahAaUTWXpsZoOecwtxi74CyneQNPTDjNg azHmvpdBVEfj7k3p4dmJp5i0U66Onmf6mMFpArvBRSMOKU9DlAzMi4IvhiNWjKVaIE2Se9BY FdKVAJaZq85P2y20ZBd08ILnKcj7XKZkLU5FkoA0udEBvQ0f9QLNyyy3DZMCQWcwRuj1m73D sq8DEFBdZ5eEkj1dCyx+t/ga6x2rHyc8Sl86oK1tvAkwBNsfKou3v+jP/l14a7DGBvrmlYjO 59o3t6inu6H7pt7OL6u6BQj7DoMAEQEAAcLBfAQYAQgAJgIbDBYhBBvZyq1zXEw6Rg38yk3e EPcA/4NaBQJonNqrBQkmWAihAAoJEE3eEPcA/4NaKtMQALAJ8PzprBEXbXcEXwDKQu+P/vts IfUb1UNMfMV76BicGa5NCZnJNQASDP/+bFg6O3gx5NbhHHPeaWz/VxlOmYHokHodOvtL0WCC 8A5PEP8tOk6029Z+J+xUcMrJClNVFpzVvOpb1lCbhjwAV465Hy+NUSbbUiRxdzNQtLtgZzOV Zw7jxUCs4UUZLQTCuBpFgb15bBxYZ/BL9MbzxPxvfUQIPbnzQMcqtpUs21CMK2PdfCh5c4gS sDci6D5/ZIBw94UQWmGpM/O1ilGXde2ZzzGYl64glmccD8e87OnEgKnH3FbnJnT4iJchtSvx yJNi1+t0+qDti4m88+/9IuPqCKb6Stl+s2dnLtJNrjXBGJtsQG/sRpqsJz5x1/2nPJSRMsx9 5YfqbdrJSOFXDzZ8/r82HgQEtUvlSXNaXCa95ez0UkOG7+bDm2b3s0XahBQeLVCH0mw3RAQg r7xDAYKIrAwfHHmMTnBQDPJwVqxJjVNr7yBic4yfzVWGCGNE4DnOW0vcIeoyhy9vnIa3w1uZ 3iyY2Nsd7JxfKu1PRhCGwXzRw5TlfEsoRI7V9A8isUCoqE2Dzh3FvYHVeX4Us+bRL/oqareJ CIFqgYMyvHj7Q06kTKmauOe4Nf0l0qEkIuIzfoLJ3qr5UyXc2hLtWyT9Ir+lYlX9efqh7mOY qIws/H2t In-Reply-To: <1b5676ab-0dc5-ef33-9d79-a2bd6090a62d@huawei.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam07 X-Rspam-User: X-Stat-Signature: c877559wf9yzfeikcbasuqdqycm7gcxy X-Rspamd-Queue-Id: 136854001C X-HE-Tag: 1781184014-436147 X-HE-Meta: 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 ElI8xLg4 VohGTedLugoUuvuhY+jaJkzPmlC5lrGhjv7eZGqKxXWfom5vTQGuK8O8kw9xmveWyoKDTU1E/GukN/KDJcINYvuwIAocbJgB/MA4Gby1hRqNOJBrYbY5IoX05rzCmH31KCYgX45LDbQ9cnhNI97L3zB5V9qwxhHTXImLxv7+5+Y6JvbyclMphefL9gvGdnYomh7E8//1YvWRoqEaN3AIIlkyGDzP2FqflFsjSD8GnhsB9VZIPUI6uoSsrMYqbpsnK0nvludC+sB64L04077PkHgwh+i1BsaKs0zuX3CKHpULwOQdw9J28DVkONx+vuIcS32x/6yB/TgzRqQI= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 6/11/26 09:36, Miaohe Lin wrote: > On 2026/6/11 13:43, Michael S. Tsirkin wrote: >> On Thu, Jun 11, 2026 at 11:35:36AM +0800, Miaohe Lin wrote: >>> >>> Do you mean repeating SetPageHWPoison on every branch? >> >> Right. >> >>> Is it possible >>> to make __free_pages_prepare changes page->flags atomically or this race >>> is specified to memory_failure? >>> >>> Thanks. >>> . >> >> >> Adding an atomic op on every fast path page allocation is, I am >> guessing, going to slow down Linux measureably. >> >> Doing it for the benefit of memory_failure, which is the slowest of >> slow paths, seems unpalatable, to me. > > Agree, it's not worth to do so. > >> >> Neither am I sure it's the only racy place - >> grep for __SetPage and __ClearPage - all these have the same issue, I >> suspect. >> >> At the same time, I'm not an mm maintainer. If you disagree, try to >> upstream a change converting all non atomics in mm to atomics, and see >> what others say. > > Since memory_failure might be the only place, this change would be unacceptable. > We should come up with a better solution. Maybe we can try repeating SetPageHWPoison > and ClearPageHWPoison at a first attempt though it looks somewhat weird to me and makes > code more complicated. And I am fairly sure we could still have some remaining races ... it's shaky. Hm ... -- Cheers, David