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 A0847CCF9E0 for ; Tue, 28 Oct 2025 14:04:30 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 043BB80160; Tue, 28 Oct 2025 10:04:30 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id F35E78013F; Tue, 28 Oct 2025 10:04:29 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DFE0D80160; Tue, 28 Oct 2025 10:04:29 -0400 (EDT) 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 C426F8013F for ; Tue, 28 Oct 2025 10:04:29 -0400 (EDT) Received: from smtpin27.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 8BF4587D32 for ; Tue, 28 Oct 2025 14:04:29 +0000 (UTC) X-FDA: 84047693058.27.99CBBDB Received: from out-184.mta0.migadu.com (out-184.mta0.migadu.com [91.218.175.184]) by imf06.hostedemail.com (Postfix) with ESMTP id D5E6818000E for ; Tue, 28 Oct 2025 14:04:27 +0000 (UTC) Authentication-Results: imf06.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=GZWIQPg2; spf=pass (imf06.hostedemail.com: domain of qi.zheng@linux.dev designates 91.218.175.184 as permitted sender) smtp.mailfrom=qi.zheng@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1761660268; 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=MfFT50NAM4YJdcJwEiZWm9eoPKYAch/I/HKN7VyhW9I=; b=TM6mtYIlH4D7gj8V1msBWduiblY6MGS9831D53ftIyNnA6PMKPfzrhPvysTc7drvOPc+bj 2fb1vBGALXXS9N6p+GEBCGlLYlIIYsnbXHaFAYPb0XaUgmBDMVZIoTOl7Q0lCwK0b6TBNz c8q4cpI/aU2f1OAKX8hrcoW8cm2Mudc= ARC-Authentication-Results: i=1; imf06.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=GZWIQPg2; spf=pass (imf06.hostedemail.com: domain of qi.zheng@linux.dev designates 91.218.175.184 as permitted sender) smtp.mailfrom=qi.zheng@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1761660268; a=rsa-sha256; cv=none; b=RImcF9jhvWapNMCDsKrcoTYrSUYHsmnTxXe0xJ/a0vOEOcxHY3+i9j/BKt9BsCdilDueqb n5AIYECS51/PVvluhH8/3Q95zyPbRRY0I6lgIJluEK2DABi7XPU1SjuzSjK+GkTF6CEV8z P6zugNCr1i2qe0iFheelYONjZO5sD9I= 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=1761660266; 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=MfFT50NAM4YJdcJwEiZWm9eoPKYAch/I/HKN7VyhW9I=; b=GZWIQPg2QKwgut9Dq3hgo3nl0aQwy3J/E5mWPtGNg4bdNwkQ+AI6uq3lfLJklHFfbHo+Pg 3E7xR05XF643Awodwuy+5roySsCLCwXL2xAjK8TTY1IsG7QNx+MN4lIQAYKtvBXnOk8QdZ 7rTdqleL9uVxBl3NuOZLwvW0LxrK80E= 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@redhat.com, lorenzo.stoakes@oracle.com, ziy@nvidia.com, harry.yoo@oracle.com, imran.f.khan@oracle.com, kamalesh.babulal@oracle.com, axelrasmussen@google.com, yuanchu@google.com, weixugc@google.com, akpm@linux-foundation.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, Muchun Song , Qi Zheng Subject: [PATCH v1 20/26] mm: workingset: prevent lruvec release in workingset_activation() Date: Tue, 28 Oct 2025 21:58:33 +0800 Message-ID: <03a26f7d8723a42c29a24b03ed318a2830faff02.1761658311.git.zhengqi.arch@bytedance.com> In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Rspamd-Queue-Id: D5E6818000E X-Rspamd-Server: rspam11 X-Rspam-User: X-Stat-Signature: uidtgodiffsp9t5zyyfh4r6md35jgmwy X-HE-Tag: 1761660267-21361 X-HE-Meta: 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 5mkoCWWd AHRz8OlNoGgBqg7TXbxUiOCkvNTSlR1JDC+5VsCM6GvCGivRku7PCHTubLyObHqFHoKJIeeHVbNqOP2ANOhadvPdMcTh6DvElAT+RHPyoh9yHXX8RfEqN2Qipob4e8lJhvcyaC1+NhxuXAuiEzxFGbPW+jyOqgeZBZPdOs87uhw6bxfBgacLZOe/QsiMzpHQtSoCpnbrp0BNH9g02Osy+FK81U5B+13VobD3I 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 --- mm/workingset.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/mm/workingset.c b/mm/workingset.c index a69cc7bf9246d..d0eb3636dcd1d 100644 --- a/mm/workingset.c +++ b/mm/workingset.c @@ -595,8 +595,11 @@ 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