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 A3AA0FF8861 for ; Mon, 27 Apr 2026 10:58:52 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 1B7656B0093; Mon, 27 Apr 2026 06:58:52 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 18F0B6B0095; Mon, 27 Apr 2026 06:58:52 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0A5156B0096; Mon, 27 Apr 2026 06:58:52 -0400 (EDT) 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 F2D586B0093 for ; Mon, 27 Apr 2026 06:58:51 -0400 (EDT) Received: from smtpin29.hostedemail.com (lb01b-stub [10.200.18.250]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 91290120158 for ; Mon, 27 Apr 2026 10:58:51 +0000 (UTC) X-FDA: 84704038062.29.43A0F2A Received: from out-179.mta0.migadu.com (out-179.mta0.migadu.com [91.218.175.179]) by imf10.hostedemail.com (Postfix) with ESMTP id B4D4BC000D for ; Mon, 27 Apr 2026 10:58:49 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=sj91+h2F; spf=pass (imf10.hostedemail.com: domain of qi.zheng@linux.dev designates 91.218.175.179 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=1777287529; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=mC/SUXF6qmjl4I2YmUCpIFnBd715RpusDKL8gxRM2m8=; b=oQY2JB7phPM5Z1AKSsh+JTIR9X8YtQ/N44rJiqPwwPLZKJsDmibaU6dEeHFx+1UsfmBBh4 lCzeGAPyybOjTl1BYU6irNd8fzc9w4c1XBi8VCXCw9Bqa4aUAmL+ha0KktejK7TbT/x7BX gE4T6/OmZ3KxDBtdlUIhSm0zivcpJlQ= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1777287529; a=rsa-sha256; cv=none; b=PEoFpN8rCsqb3ZO8UQuzApTN4W93jb/sozRlYi9uFRwGcT5yZ60l2SiKW1uNJLOGjSnXU3 03GvIdv8VLr4eC8LshmdC1FHWjaRVrnzT3YmLI/ysisbXOm3mEVvyoUrmuJRCpVLwWNwtJ VUJKoFXvtZrJM9lNFw8Y71uhKsRskWo= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=sj91+h2F; spf=pass (imf10.hostedemail.com: domain of qi.zheng@linux.dev designates 91.218.175.179 as permitted sender) smtp.mailfrom=qi.zheng@linux.dev; dmarc=pass (policy=none) header.from=linux.dev Message-ID: <93cab3a3-1a67-4ac0-a818-f333d8017bc7@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1777287526; h=from:from: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:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=mC/SUXF6qmjl4I2YmUCpIFnBd715RpusDKL8gxRM2m8=; b=sj91+h2FCn6FNfkkxcVlMhdGDID905wb6k5PpVtes3BGCdCrQDPp/vXU+amHHWxaeF/Nak u8EDm/WFOVn3PvlJF6yeIYWeu8YT+q4Tm+g6N0lnrAc1xqRxnXkhl9hkMOhfvHF+qQGx/j syfIfRAlYok9/6+Cc8WoRf+2Iy+48Q4= Date: Mon, 27 Apr 2026 18:57:52 +0800 MIME-Version: 1.0 Subject: Re: [syzbot] [mm?] WARNING: bad unlock balance in do_wp_page To: Andrew Morton Cc: shakeel.butt@linux.dev, syzbot , Liam.Howlett@oracle.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, ljs@kernel.org, surenb@google.com, syzkaller-bugs@googlegroups.com, vbabka@kernel.org, Muchun Song References: <69edca15.170a0220.38e3f1.0000.GAE@google.com> <20260426034938.db29d74982a8eb8463f8cf3a@linux-foundation.org> <20260426105532.43768b24a42744f1b52fdff2@linux-foundation.org> <3591c663-a4a9-4c22-97cf-b58b2e7d8a41@linux.dev> <20260427034402.096cb95de92bec15becc78bb@linux-foundation.org> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Qi Zheng In-Reply-To: <20260427034402.096cb95de92bec15becc78bb@linux-foundation.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: B4D4BC000D X-Stat-Signature: e8mwwe1uxhm7jp5wazy3bg6e5qnrmqm8 X-Rspam-User: X-HE-Tag: 1777287529-317594 X-HE-Meta: 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 RkHci45M E1+hnOJ+EFILsFlTlGxvgo74tzimNU0JX6YH3vvXtzrI/SKI5XqfPNooyfyUw65adhk44Okry2vLtuEwgY2Nee8dCgbZihMbK2uJlbCXS1t4zUajrbtUZ533B29eDvNuEnzrYCO2IcrwrGRRLBiYuXcwscEEUHjdfVwdbvwZTUZtaJdKSCCeR9RELjVNzWAUv6ku5qcG4jfLgbNb5lmLXjanC4k3Hm5U3xg9D7AFco/I4bCgyVyYw4u8necwZMQzunPKJqXj9HgbEUxvSSs0MDTFDHLaYbQWiHE0Hco3nkJcjer3Ga4FIO1ZMndfx5IMiHVHRTfUUTaOmZq5ec/H7y/GJGgYH6p7TTkz2sju954NSu82btptPJNJp8i4DVtFmPfBw+BDlEJjt0AMTZaLpNckr9/Xm8RWq4f4Ao1LyxcfoFP3YI8fYcxKo9o5ml00Zhxm942KeFy+uBo9EaJBHJFkFuWnBG7XCKWSP Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 4/27/26 6:44 PM, Andrew Morton wrote: > On Mon, 27 Apr 2026 17:43:38 +0800 Qi Zheng wrote: > >> >> Alright, it seems I have successfully reproduced it: >> (The reproducer is attached at the bottom of this email.) > > That's a lot of code. Thanks for doing that. Maybe there's something > here we can put into selftests/ If we are inclined to drop rebinding, then perhaps it's unnecessary to add selftest for it. ;) > >>>> >>>>> However, in a production environment, this is practically impossible. >>>> >>>> Can you expand on this? >>>> >>>> sysbot isn't a production environment ;) >>> >>> Rebinding only works when the hierarchy is completely empty. This is >>> generally not the case in a production environment (e.g. when systemd >>> is used). >>> >>> BTW, it seems rebinding is about to be deprecated: >>> >>> cgroup1_reconfigure >>> --> pr_warn("option changes via remount are deprecated (pid=%d comm=%s)\n", >>>             task_tgid_nr(current), current->comm); >>> >>> Also, it appears the current memcg subsystem assumes that >>> cgroup_subsys_on_dfl(memory_cgrp_subsys) cannot be changed at runtime. >>> (Please correct me if I missed anything.) >>> >>> If we can get a reproducer, we can try the following fix, or simply drop >>> rebinding altogether? > > We'll want something which is applicable to 7.1-rcX please. Removal of > rebinding sounds like something we'd address in 7.2 or later. Got it. > >>> From 6ae41b91339625dd7bf0f819f775f26e78171a73 Mon Sep 17 00:00:00 2001 >>> From: Qi Zheng >>> Date: Mon, 27 Apr 2026 11:20:21 +0800 >>> Subject: [PATCH] mm: memcontrol: fix rcu unbalance in >>>  get_non_dying_memcg_end() >>> >>> Signed-off-by: Qi Zheng >>> --- >>>  mm/memcontrol.c | 30 ++++++++++++++++++++---------- >>>  1 file changed, 20 insertions(+), 10 deletions(-) >> >> With the above patch applied, the warnings are gone. >> >> If no one objects, I'll submit the formal fix. Or should we actually >> just remove rebinding instead? > > I suggest we just fix up current -rc please. OK, will do. Thanks, Qi >