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 8CF26EFD204 for ; Wed, 25 Feb 2026 07:55:13 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id EB2236B008A; Wed, 25 Feb 2026 02:55:12 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id E6F376B00BB; Wed, 25 Feb 2026 02:55:12 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D88DC6B00BD; Wed, 25 Feb 2026 02:55:12 -0500 (EST) 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 C5A9D6B008A for ; Wed, 25 Feb 2026 02:55:12 -0500 (EST) Received: from smtpin22.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 741A38BC0E for ; Wed, 25 Feb 2026 07:55:12 +0000 (UTC) X-FDA: 84482218464.22.A0B280C Received: from out-188.mta0.migadu.com (out-188.mta0.migadu.com [91.218.175.188]) by imf16.hostedemail.com (Postfix) with ESMTP id B9CE518000A for ; Wed, 25 Feb 2026 07:55:10 +0000 (UTC) Authentication-Results: imf16.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=mCSZNJHf; spf=pass (imf16.hostedemail.com: domain of qi.zheng@linux.dev designates 91.218.175.188 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=1772006110; 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=HnmFwHvsMTnTTmTxaDaXSNXj2pGFLQguy6RatY5l3dgNHLTdnvkmXqZfFpeTlChtMkNugr rh1uT5AhQBdwdf8deP6OEi7cp+z/Df0ee17Z2FimpVjMmgeAs1ptc08sEZeW9XOay9gLd5 fjN4iB6ZDVp25W0lkbnEbQmT40RDfJY= ARC-Authentication-Results: i=1; imf16.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=mCSZNJHf; spf=pass (imf16.hostedemail.com: domain of qi.zheng@linux.dev designates 91.218.175.188 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=1772006110; a=rsa-sha256; cv=none; b=kcTUzel7UVGr8VqLIcpF0/Cs5n5FDxs6SbL/yTa0pejxhzGU/MTPeRF/x8MZAvjEoomyNj QRMdJQc5az1ocGr7W0Igcio8LlB5FJHhE5s+tieLPWyO6AI+EPleU66XeZ+VlX3hkJ6W5V d5v4bRxElMw39jMS+3ef59uwiZ4ZnoM= 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=1772006108; 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=mCSZNJHfd90ZlK4cL+EpjAjgG1SmuZQe0G4TFl8RoR7n2xLpoLbc6jStwi1xux9axli6/6 EQODJy4LkMiQAImbBjOMfcXIqUhYX5TsUF6lfISMhfG7fGhrsibZOPahSWZL8MZcvLqoWC OAqKtL7dmPmtfU2i3Fjaj2AwhHi975w= 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 v5 22/32] mm: workingset: prevent lruvec release in workingset_activation() Date: Wed, 25 Feb 2026 15:53:05 +0800 Message-ID: In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Rspamd-Server: rspam05 X-Rspam-User: X-Rspamd-Queue-Id: B9CE518000A X-Stat-Signature: sejcatiety79arskpwxu6us3bdcrz56x X-HE-Tag: 1772006110-537487 X-HE-Meta: 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 3srso7al /IaABswiy3OuEvmAk1pfe7wHPz8B17uFGaXLEuYRYvlRhIyCxmW3ERaiuyek4K5konvs9kiYvFPuZa65zOFSu9A+e6LV3Aw+LA6nuKItr62XqjzLjjBShxe+X4rT6l6FJZIL1Cl55dxG8vZRKnQDspawM8n5vPwjFCC1UhtmOk5R2qAqpQy7hG4UzL8l8wb4Tw18w0eluxM9h0w8eJpYPt7P9esJJkbkLFrhEBp4xun2fbSDKhmvnZXWln9Bl3Hv8nbEq0LXgzsS1MS5SwIQGmjXK3UgGeQin6SVKHkTUUHxxT/0Z0KkfDUDAYYacfcljvPr7 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