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 B0A19D29FF1 for ; Wed, 14 Jan 2026 11:35:30 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 26C096B00B9; Wed, 14 Jan 2026 06:35:30 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 239D26B00BB; Wed, 14 Jan 2026 06:35:30 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1181E6B00BC; Wed, 14 Jan 2026 06:35:30 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id F25556B00B9 for ; Wed, 14 Jan 2026 06:35:29 -0500 (EST) Received: from smtpin05.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 9FEDB16048E for ; Wed, 14 Jan 2026 11:35:29 +0000 (UTC) X-FDA: 84330363978.05.4FCBCAF Received: from out-171.mta0.migadu.com (out-171.mta0.migadu.com [91.218.175.171]) by imf14.hostedemail.com (Postfix) with ESMTP id E3E66100003 for ; Wed, 14 Jan 2026 11:35:27 +0000 (UTC) Authentication-Results: imf14.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=GkQroMKg; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf14.hostedemail.com: domain of qi.zheng@linux.dev designates 91.218.175.171 as permitted sender) smtp.mailfrom=qi.zheng@linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1768390528; a=rsa-sha256; cv=none; b=weClWpG2Yz8mV9S4C8+7V3HgksCBpVXFHwQOaT3yCSi36MrCvI7aJxslC7UGyc7DNVUV8Y /Y/5s2ajv4JJZA0SfJaQJEza07+9ZtrrOyt/OzZALwtROZt5gqlP+FuvuhSmWSfWMkFhLa qJHyovffcpKcAf/cF/BRV4UTY/dYC9U= ARC-Authentication-Results: i=1; imf14.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=GkQroMKg; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf14.hostedemail.com: domain of qi.zheng@linux.dev designates 91.218.175.171 as permitted sender) smtp.mailfrom=qi.zheng@linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1768390528; 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-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=Z51xqOUPrAhoh0O0GpdBH64DgayE69nJ4AY48cemOmg=; b=sWTY71V259V3/uc9LGjXXRdZ5/O93AXckwhjYsKlIdjdHKeGsFZzMwqH76ZB8xsCrPAW7o vVlH0slcjtwC3QXBGO0twuci7sOPU+0b3AGZOkZBHxH5SLYDYnGzHb2nAr1OJp7qCTT4ag ElIUJXIQKJKbhlBVWrTEJq7YmRcCrcA= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1768390525; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Z51xqOUPrAhoh0O0GpdBH64DgayE69nJ4AY48cemOmg=; b=GkQroMKgudviGh4+T3T5BnePjIc1sCeCfGOszqh4Cpf/7jz08mH0bGrBlPoQrr20CERWHc S1ty/PC/trZydeZrWsSp+zOKUJ65SUr5t1kUkrueBtRe+npVCrQ5t5mroPuMDsbzUyq1TH FuVn0xlRBuYmhx2Pkoecm8EYYvDz7b0= From: Qi Zheng To: hannes@cmpxchg.org, hughd@google.com, mhocko@suse.com, roman.gushchin@linux.dev, shakeel.butt@linux.dev, muchun.song@linux.dev, david@kernel.org, lorenzo.stoakes@oracle.com, ziy@nvidia.com, harry.yoo@oracle.com, yosry.ahmed@linux.dev, imran.f.khan@oracle.com, kamalesh.babulal@oracle.com, axelrasmussen@google.com, yuanchu@google.com, weixugc@google.com, chenridong@huaweicloud.com, mkoutny@suse.com, akpm@linux-foundation.org, hamzamahfooz@linux.microsoft.com, apais@linux.microsoft.com, lance.yang@linux.dev Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, Muchun Song , Qi Zheng Subject: [PATCH v3 22/30] mm: workingset: prevent lruvec release in workingset_activation() Date: Wed, 14 Jan 2026 19:32:49 +0800 Message-ID: In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Rspam-User: X-Stat-Signature: r6ogpier1jtdcze5ydxgafm7ybb1pmhx X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: E3E66100003 X-HE-Tag: 1768390527-450241 X-HE-Meta: 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 CO8PVJwu Saq66QVYzzAyPhBOFXJzTntWWYLixPWF/2E+9VFJZ13EndtCt45iG8Rto5pBRj75Hn1hSOB1NeynkXio3WsMCMTI6Mib9MaZWm/st+JoDQ8kQxFNhQDO87YEv5JjySbJ9ylP4/rjUvdfK/+AbHGwZxrV9qqujmbzgwD0ISL5I/6lW01C8fW+CeTYtxutduCAU64Pfqx7NGwkXpAegU4aOgTI8/2UdNxKmiZQ9eCHw6DDVfNxXddf/AZ16GQVV312P802azQXl5XEiFRVWCTL/xmTjq+YCCzyJ7S8Mkt5BXsOVrDXuTUVy9CBavj3Azq7P/Fkq X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: Muchun Song In the near future, a folio will no longer pin its corresponding memory cgroup. So an lruvec returned by folio_lruvec() could be released without the rcu read lock or a reference to its memory cgroup. In the current patch, the rcu read lock is employed to safeguard against the release of the lruvec in workingset_activation(). This serves as a preparatory measure for the reparenting of the LRU pages. Signed-off-by: Muchun Song Signed-off-by: Qi Zheng Reviewed-by: Harry Yoo Acked-by: Johannes Weiner Acked-by: Shakeel Butt --- mm/workingset.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/mm/workingset.c b/mm/workingset.c index 5fbf316fb0e71..2be53098f6282 100644 --- a/mm/workingset.c +++ b/mm/workingset.c @@ -596,8 +596,11 @@ void workingset_activation(struct folio *folio) * Filter non-memcg pages here, e.g. unmap can call * mark_page_accessed() on VDSO pages. */ - if (mem_cgroup_disabled() || folio_memcg_charged(folio)) + if (mem_cgroup_disabled() || folio_memcg_charged(folio)) { + rcu_read_lock(); workingset_age_nonresident(folio_lruvec(folio), folio_nr_pages(folio)); + rcu_read_unlock(); + } } /* -- 2.20.1