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 9C6D0606A31E for ; Tue, 27 Oct 2026 20:32:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=cUUj8rbd Received: by kanga.kvack.org (Postfix) id 9DDFA6B076D; Tue, 27 Oct 2026 16:32:33 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9B6366B0776; Tue, 27 Oct 2026 16:32:33 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8CCB56B0778; Tue, 27 Oct 2026 16:32:33 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 6D2A76B076D for ; Tue, 27 Oct 2026 16:32:33 -0400 (EDT) Received: from smtpin19.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay04.hostedemail.com (Postfix) with ESMTP id B8CC91A0ADB for ; Tue, 27 Oct 2026 20:32:32 +0000 (UTC) X-FDA: 85369554144.19.A807655 Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf28.hostedemail.com (Postfix) with ESMTP id 0ECC5C0009 for ; Tue, 27 Oct 2026 20:32:30 +0000 (UTC) Authentication-Results: imf28.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=cUUj8rbd; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf28.hostedemail.com: domain of harry@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=harry@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1793133151; 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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=86fhQATGDo+8MDnZqTEUILQavbmG5W/eLVJguZT8p6Y=; b=f0PPQmKyaQXgFApNvoc6ak0nKCcqqla0z76nU+szlkISECS5iWKPD/wBys/Uppo2ddFu5K h2xDl0j0gE5yioZrMexd2ydhDjEIaLmoYJe76H90TtTa4Scx7RouvvjZJ2YhHPH4++xlEq vLYli6JBA7YpZR+W3FNm+TCUW9opXfQ= ARC-Authentication-Results: i=1; imf28.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=cUUj8rbd; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf28.hostedemail.com: domain of harry@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=harry@kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1793133151; b=z56Ooyu/2h2/FFZs000eqzkjw4QyrcLLSatKmfzAVh4OX+oDv4R4DAV2VHmbeH694hEFRx 2b89/1jevjk9VeaD7ANKbu79llPC45EBqkrLyDQKWqOo6YQktqob9yBx8Ym6D2iAKTUYVW 8DoN2x07ZTHOMOiW3Td/ytHOR96MA+c= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 20C2043075; Tue, 27 Oct 2026 20:32:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6D5A11F01825; Tue, 27 Oct 2026 20:32:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793133150; bh=86fhQATGDo+8MDnZqTEUILQavbmG5W/eLVJguZT8p6Y=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=cUUj8rbdB8sxeJkMuDL4RCOdrYbrRplzvevKwnxFuwaEcH7HP+ENffudf2T0mpEpv 5IgYZPx4U8OILjqSgrQVM2ZVtEuU+s+iUCRqr37O0SlFEfCwYP6WH8sUr54mzsCt1s iMf6J0wk9xYuuAD3vV+C40mhUS8iHT1njIORZz73KfNOXA2HaiIMPxjzwaUpjzGq0a +HDzAe6Y83Ik9oMrM+EDzTEENc7lTwdaNWApON+amLO666KTk6vgqAwdt/I26Z5K2e tnFRDkmrRt4vDlqitIfQMOzf4AtEOnF0EKCtlUHfO8gpTP2ZD2//SXJTbcFDzwJNgN ttZ0nsquNOB0g== Date: Tue, 27 Oct 2026 20:32:28 +0000 From: Harry Yoo To: "David Hildenbrand (Arm)" Cc: Andrew Morton , Johannes Weiner , Michal Hocko , Qi Zheng , Shakeel Butt , Lorenzo Stoakes , Kairui Song , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Baoquan He , Baolin Wang , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Kees Cook , Peter Zijlstra , Jann Horn , Pedro Falcato , Hugh Dickins , Pasha Tatashin , Pratyush Yadav , "Matthew Wilcox (Oracle)" , Jan Kara , Zi Yan , Lance Yang , Rik van Riel , Alistair Popple , Nico Pache , Ryan Roberts , Dev Jain , Usama Arif , Kiryl Shutsemau , Matthew Brost , John Hubbard , Peter Xu , Will Deacon , "Aneesh Kumar K.V" , Nick Piggin , Oscar Salvador , Minchan Kim , Muchun Song , Xu Xin , Chengming Zhou , Chris Li , Kemeng Shi , Nhat Pham , Youngjun Park , Gregory Price , Joshua Hahn , Rakie Kim , Ying Huang , Jason Gunthorpe , 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, stable@vger.kernel.org, Josef Bacik Subject: Re: [PATCH 43/46] mm/vma: don't leak the charge for stack growth Message-ID: References: <20261027-fixes_core-v1-0-6f74bec9a5bb@kernel.org> <20261027-fixes_core-v1-43-6f74bec9a5bb@kernel.org> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261027-fixes_core-v1-43-6f74bec9a5bb@kernel.org> X-Rspamd-Queue-Id: 0ECC5C0009 X-Stat-Signature: cqtjoxipyj433kyuzxmbjcptk66w1h14 X-Rspamd-Server: rspam06 X-Spam-Status: No, score=-11.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS autolearn=unavailable autolearn_force=no version=4.0.1 X-Rspam-User: X-HE-Tag: 1793133150-748236 X-HE-Meta: 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 fUXs+17e P89igjh+b1ujDSFwVIDyhrncl5/Ln807EzFHN/ZJL52aWzNbZcjXejHEbEhzoeXwh9EEWMacjNq6h/sR34K4W/vuL5VSeP3/8LZRBATMu3QpsjH2k/EZeCiYhNo/dRIOqxg9FODr4OBb8yMMsCWMRxBck+NDXn1nWWZ+wmqdoVBCsorwoeKyX/QcybO1RIxl6Tv0+ukTPP50IaHNWqOOmRACYUTww8Lc/qDuOauMRQh/Uca084Guv54dDMk/lfeIF1unEeHnxBe9/dkrsqbPSBPMb+3ycevkOwo50zdL0qVMkJ/18o2XXPDOtSPnmLStZQVE3f5EVk6nahH6CPg24cQFkFmZ+6ooDdzx8nDe1f21cFhhdu5HM9g/OgQltO3aaFfF8F0HQyGcKSqmHl5vXQjJQQaT3EQfrNPNX 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 12:18:03AM +0100, David Hildenbrand (Arm) wrote: > acct_stack_growth() charges stack expansion even without VM_ACCOUNT. > This can happen for read-only or MAP_NORESERVE mappings created with > MAP_GROWSDOWN. Unmapping these VMAs does not release the charge, leaking > Committed_AS. > > Only check and charge growth for VM_ACCOUNT VMAs, matching mremap(). > Unaccounted growth skips the overcommit check while remaining subject > to the other stack-growth limits. > > Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") > Cc: stable@vger.kernel.org > Reported-by: Josef Bacik > Reviewed-by: Lorenzo Stoakes (ARM) > Signed-off-by: David Hildenbrand (Arm) > --- Looks good to me, Reviewed-by: Harry Yoo (Meta) Maybe worth having a warning when it's accounting w/o VMA_ACCOUNT_BIT or let those helpers skip when there's no VMA_ACCOUNT_BIT set... -- Cheers, Harry / Hyeonggon