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Tsirkin" Cc: "David Hildenbrand (Arm)" , linux-kernel@vger.kernel.org, Miaohe Lin , Naoya Horiguchi , Andrew Morton , Oscar Salvador , Hidehiro Kawai , Rik van Riel , Vlastimil Babka , Lorenzo Stoakes , "Liam R. Howlett" , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Johannes Weiner , Zi Yan , Baolin Wang , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Christoph Lameter , David Rientjes , Roman Gushchin , Harry Yoo , Hao Li , Kiryl Shutsemau , Byungchul Park , linux-mm@kvack.org, linux-cxl@vger.kernel.org Subject: Re: [PATCH 0/2] mm: memory-failure: fix HWPoison flag race with non-atomic page flag ops Message-ID: References: <0b5f8b4b-d7dc-4b79-9555-a5b36265f3a9@kernel.org> <20260629030657-mutt-send-email-mst@kernel.org> <4f5ba5d6-246c-4430-9737-e8dd8e4c5142@kernel.org> <20260629092856-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260629092856-mutt-send-email-mst@kernel.org> X-Rspamd-Queue-Id: 7EAE940007 X-Stat-Signature: k8f6u76bpk4spjd1kqaycpnqxq86w331 X-Rspam-User: X-Rspamd-Server: rspam03 X-HE-Tag: 1782766560-521335 X-HE-Meta: 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 XCdRFD2n rmCIEdKiEi8mMvFopw3d6EniR8I7I2Era+j0d6FDhuekoiimpd5R43JDfrX5aiAvaUk+txin+kwLi5DRKtScqeHFMDzU+brGsHZx4oHdvh0LsCrH7g6115jj7DOqEfq8t2BtJ9wVRfLikNN71W59agbGAx/bTFrA1MRT/O8b9DpE3phYAACRFPMW4d7xl9yrykw+or5AHKhpmjHZkTXfogQcmgrfMTUtrnwnJ4ZLAFaYjXRFnblJW4jfnRO07BKIluWcvcbGSmrZxsD75MfnBxfP54BojWi3tXmwc3wjXUnn5VyKyUKRq3W5Z+g== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > > Or if there are actually more performant alternatives that we could use. (I > > still doubt that using atomics is ok in general) > > Right now I'm thinking of looking at something like stop_machine maybe. There can be (rare) cases where yoy get a lot of memory errors in a flood. While memory-failure doesn't need to be particularly optimized, it shouldn't be excessively slow or impact the rest of the machine. stop_machine is a big hammer that is likely to violate most of this. -Andi