From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 1BFBD606A31A for ; Wed, 28 Oct 2026 15:54:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=bIPJgOc3 Received: by kanga.kvack.org (Postfix) id 014076B05B0; Wed, 28 Oct 2026 11:54:24 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id F06506B05B1; Wed, 28 Oct 2026 11:54:23 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DCE986B05B2; Wed, 28 Oct 2026 11:54:23 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id BAB3C6B05B0 for ; Wed, 28 Oct 2026 11:54:23 -0400 (EDT) Received: from smtpin08.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 373F1C0151 for ; Wed, 28 Oct 2026 15:54:23 +0000 (UTC) X-FDA: 85372482006.08.DF781DD Received: from mta1.migadu.com (out-57.mta1.migadu.com [95.215.58.57]) by imf15.hostedemail.com (Postfix) with ESMTP id F092CA0003 for ; Wed, 28 Oct 2026 15:54:20 +0000 (UTC) Authentication-Results: imf15.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=bIPJgOc3; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf15.hostedemail.com: domain of lance.yang@linux.dev designates 95.215.58.57 as permitted sender) smtp.mailfrom=lance.yang@linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1793202861; 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=tTZpPE9gJn7s96098K7j6uvB27YaMf32yiUhWF9ATX4=; b=VZunTNCvkH20QtpXnO8HovITH3tdIBJfMmRqsyqBRRa+KQU/WSk4L02tLnRuU+JPQbTxAh Z+jL2LZyriW/foG5Ojgob0Nalig9lJIUK64z7JUY924EK4Va99v4yLhXZjOps4b9qmV8QX MgUN10onKPY/+Lr3UewkSOYuIxtQCdw= ARC-Authentication-Results: i=1; imf15.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=bIPJgOc3; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf15.hostedemail.com: domain of lance.yang@linux.dev designates 95.215.58.57 as permitted sender) smtp.mailfrom=lance.yang@linux.dev ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1793202861; b=Wf/J8JeqQUzX7a2qc4NbSHcuWPIRRe48XQ8tUTmT3okkBBK2ovl1gKU2vfRZ+2xmVGUrPO tg3MO+O9181vEMmSxxZ+LVLErF0u+J22lE/h12QhmjsfRKAIehR7H/AnbTh7ZALn5rQ6EK hxDB4vIAFY6fa2QUq55ftlPbrP4MVqw= X-Envelope-To: linux-mm@kvack.org DKIM-Signature: a=rsa-sha256; bh=tTZpPE9gJn7s96098K7j6uvB27YaMf32yiUhWF9ATX4=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1793202859; v=1; x=1793807659; b=bIPJgOc3iPcKTa1DXojN+YH2KEJcCalwAlquT1K3q2vP78rezERhjcEiyPnYf3XJJi+zm40e VZ8Y7h0Sg0LHwZ3RIB6hSZlxVJqtHyTLtmTMwa/Q5NiV5ZlDRHprLtwNr+zvun7UOnbjrZLyZOI 1EXHQla+Wo0nAnoYaUtKJ62U= X-Envelope-To: linux-mm@kvack.org Received: by smtp.migadu.com with ESMTPS id f81f3d53b1ebb019; Wed, 28 Oct 2026 15:54:18 +0000 X-Mizu-Trace-ID: f81f3d53b1ebb019 X-Migadu-Flow: FLOW_OUT From: Lance Yang To: david@kernel.org Cc: akpm@linux-foundation.org, hannes@cmpxchg.org, mhocko@kernel.org, qi.zheng@linux.dev, shakeel.butt@linux.dev, ljs@kernel.org, kasong@tencent.com, baohua@kernel.org, axelrasmussen@google.com, yuanchu@google.com, weixugc@google.com, baoquan.he@linux.dev, baolin.wang@linux.alibaba.com, liam@infradead.org, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, kees@kernel.org, peterz@infradead.org, jannh@google.com, pfalcato@suse.de, hughd@google.com, pasha.tatashin@soleen.com, pratyush@kernel.org, willy@infradead.org, jack@suse.cz, ziy@nvidia.com, lance.yang@linux.dev, riel@surriel.com, harry@kernel.org, apopple@nvidia.com, nico.pache@linux.dev, ryan.roberts@arm.com, dev.jain@arm.com, usama.arif@linux.dev, kas@kernel.org, matthew.brost@intel.com, jhubbard@nvidia.com, peterx@redhat.com, will@kernel.org, aneesh.kumar@kernel.org, npiggin@gmail.com, osalvador@suse.de, minchan@kernel.org, muchun.song@linux.dev, xu.xin@linux.dev, chengming.zhou@linux.dev, chrisl@kernel.org, shikemeng@huaweicloud.com, nphamcs@gmail.com, youngjun.park@lge.com, gourry@gourry.net, joshua.hahnjy@gmail.com, rakie.kim@sk.com, ying.huang@linux.alibaba.com, jgg@ziepe.ca, linux-mm@kvack.org, linux-kernel@vger.kernel.org, kexec@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-cxl@vger.kernel.org, mason@kernel.org, stable@vger.kernel.org Subject: Re: [PATCH 13/46] mm/huge_memory: fix truncate racing with PMD zapping Date: Wed, 28 Oct 2026 23:54:11 +0800 Message-ID: <20261028155411.50458-1-lance.yang@linux.dev> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20261027-fixes_core-v1-13-6f74bec9a5bb@kernel.org> References: <20261027-fixes_core-v1-13-6f74bec9a5bb@kernel.org> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: F092CA0003 X-Stat-Signature: 9jyt3nc37cqpcgty8mmd948hta673mad X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=4.0.1 X-Rspam-User: X-HE-Tag: 1793202860-257190 X-HE-Meta: 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 vekwg3r+ HB4tLaU26TcGCr5mETVyYywm66hLWpLCySswHHyNSZ1xwGPxDtLMZAyT6thmPltqB2ibsjG3YhZEcZOwdShNwOHSnodEYByHlT83aprUtJuD0pEFNf+fR802UPGDbcYGK3eWh6nc83y/OS3NFB37NoC3mJkvyXeGxiRH0Mun6m6QICi95CpMZVBWtjphxSfcj9MSMmgSL5hzjlvO6mXpERD2i+Pz6JZX0bTbsjFtLvaZvErwNMOTchp3Zla4Uymt9VmzUSLF2bKogF8+JRy+2yokV/Li0u5zH8TeG+eWaHcYYUrur6DTDczl+wo78I1YNJBJPjxTFwBeZIozPp/pQeRVfbOM1vjt6Ji5M2/ajvXnpAnoL9ktnIZyJCGkzIuejMjO9btvzpTJgaigWmw46ARrjBtdnAnWHT8Nw Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Tue, Oct 27, 2026 at 12:17:33AM +0100, David Hildenbrand (Arm) wrote: >From: Chris Mason > >zap_huge_pmd_folio() removes the rmap before calling folio_mark_dirty(). >If this was the last mapping, truncation can skip unmapping the folio >and proceed without waiting for the PMD lock, racing with dirtying. > >ifs_set_range_dirty() can oops if MADV_DONTNEED races with >ftruncate() on XFS, when we get the folio set dirty after it was found >to not be mapped anymore. > >Move folio_mark_dirty() and folio_mark_accessed() before rmap removal, >matching the PTE zap path. This keeps the folio mapped while updating >its state, so truncation must wait for the page table lock. > >Fix generated by an LLM and sent by Chris Mason in private. > >Fixes: fe6cf984939d ("mm/huge_memory: transfer the pmd dirty bit to the folio on zap") >Cc: stable@vger.kernel.org >Signed-off-by: Chris Mason >[ david: simplify comment and description ] >Signed-off-by: David Hildenbrand (Arm) >--- Good catch! Reviewed-by: Lance Yang