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 D1A81F30951 for ; Thu, 5 Mar 2026 11:58:04 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 49EC96B00BB; Thu, 5 Mar 2026 06:58:04 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 473116B00BC; Thu, 5 Mar 2026 06:58:04 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 38CAE6B00BD; Thu, 5 Mar 2026 06:58:04 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 289FF6B00BB for ; Thu, 5 Mar 2026 06:58:04 -0500 (EST) Received: from smtpin27.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id E6054C1D12 for ; Thu, 5 Mar 2026 11:58:03 +0000 (UTC) X-FDA: 84511860846.27.B69E55A Received: from out-174.mta0.migadu.com (out-174.mta0.migadu.com [91.218.175.174]) by imf09.hostedemail.com (Postfix) with ESMTP id 4037B140005 for ; Thu, 5 Mar 2026 11:58:02 +0000 (UTC) Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=nqgE8YuM; spf=pass (imf09.hostedemail.com: domain of qi.zheng@linux.dev designates 91.218.175.174 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=1772711882; 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=f+e+MrbxStkCyw/Uqa2jpcsS2d2D2I5PIhTEX7t4Mug=; b=Ac95w992MiIUcRNu50fPeqIebyQt31xcwmszHJeG8yZmKWbRjpMyYtjo2CEt19xepWZs3Y GPFgaWDfdt8bhPmS+/f4X9wmVedD/9u5APcHBCUoez5pAklP+7gcDAyPBRmDcl2VfT7Inl YrUolwXH20BMsRqcgXbZwZdAmpUwHsY= ARC-Authentication-Results: i=1; imf09.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=nqgE8YuM; spf=pass (imf09.hostedemail.com: domain of qi.zheng@linux.dev designates 91.218.175.174 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=1772711882; a=rsa-sha256; cv=none; b=OqeQI8qbV543ABSNvbLKsz/e7dMrlZummV/HWHupCA0SEWMMJdM4ol1tELYtE0cxLwY6ji cD6MNAJkYC1iOzL3fu/wcir1ELzRwy+IVjcsS9L7cc1M2ar/lmAJ47cKwI2ghCrzjIF624 S5v62sIU6ofyn2f6pinsqEaq2y8cdxA= 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=1772711880; 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=f+e+MrbxStkCyw/Uqa2jpcsS2d2D2I5PIhTEX7t4Mug=; b=nqgE8YuMYpDeMSH70KNVeXPS0W/PRINNke44gBx7AlwJ4YmwlZE50vf2Y4Jo1VuXMWZp62 KPKir4dzqgTTlpd9/Attzl0mRO9jxg8AH2zpwt1vEZFsP+YMJW7CyX4oq3KY/eLsrnIwsf T0X1I8DTJfskCOaiY4Ntpo66q467K2k= 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, bhe@redhat.com, usamaarif642@gmail.com Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, Muchun Song , Qi Zheng Subject: [PATCH v6 22/33] mm: workingset: prevent lruvec release in workingset_activation() Date: Thu, 5 Mar 2026 19:52:40 +0800 Message-ID: In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Rspamd-Queue-Id: 4037B140005 X-Stat-Signature: g1axijwzrgaanmkzciascr5oorpy8fh6 X-Rspam-User: X-Rspamd-Server: rspam06 X-HE-Tag: 1772711881-230174 X-HE-Meta: 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 DWt/wqn6 gYqVZe+T3lSojyvYDXIFUxDeTViWnRBxPRqNewetgFbpC3sxtECkslzefrNgLH22Gz601OxaOG0tlojEw2ugQjW0i9/dDAXpR0fAjH3a6275iFG9+rdeXth9hS6R7JfX36go6AFIzNUwVPLyvBhM5KS7jD0vt/RlTjagHLm/3fS6bmxUVhr7NrSDh+gO+POPat8h6G8pQ/BzvEBC+jCyUaQaXWMZwwRh/pi7ePrChXqWfUU39104XS+KLzwhsqX12YSKiqYLxfdhBa7tXrQAQuYvzrbghJcJ7ifhH+h5bg8dRqRwJ1FAHHCDC0LUU9I6HNI1Y 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 2de2a355f0f86..95d722a452e1c 100644 --- a/mm/workingset.c +++ b/mm/workingset.c @@ -603,8 +603,11 @@ 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