From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-174.mta0.migadu.com (out-174.mta0.migadu.com [91.218.175.174]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A0CD53909A2 for ; Mon, 13 Apr 2026 22:28:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.174 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776119341; cv=none; b=B5j/Y4HaYs37dLZQHM6FEni9Fpx1vt0+6M+ITbw+gaN6skT6jzag7v68XHjM2WykcGNSx+FoeyRP0eTaIIxH6eu4EBZqTCx55PwIWdQQTP1Pgs8VM04mqyXB5IniCS2UtUW5+DBqt6kzCDTKxaCYGoRHFcrRsQjyu9+8IdE2y14= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776119341; c=relaxed/simple; bh=Zu9t9xMwSwTdbUO8QXwwxTD/AJlEofFg31G2lARa+/o=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=kGGERGgoyXRPIQSplsSeLcfU6HeDah3LryOUsqRpXflWaIukiBHHbOBS82oduj+/H9JIQWS4MtaWdZQ3iBfFYo4RgMtiZ4KFrcgQnVp1oMbIcpAFYDrr/pIIR2w6uDEginFjFCgN2V4lBA6m6yNNpWwtAU0X7PX2PSq58/RUx30= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=Acn3ot68; arc=none smtp.client-ip=91.218.175.174 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="Acn3ot68" Date: Mon, 13 Apr 2026 15:28:52 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1776119337; 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: in-reply-to:in-reply-to:references:references; bh=R0C0oTbgMZYbhrAvkMy0ApjkIhijnhBgwg9sMmLsR0w=; b=Acn3ot68zMGKTsDYvK5Aa4s1RXOMEuYQGZqR09u3VG6a016vJp8EKZeK2gFbESKUvWoT0Q 0SarXFhI/s/uQHW9HYZOEIS6bKHCakE8/CMF4YrhNIlAFdkEoKqBkFrIOdowTV4y4HWI3M mOVL5DjirDprGIsRuX9t3ZRr2Rhp5gk= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Shakeel Butt To: syzbot Cc: akpm@linux-foundation.org, cgroups@vger.kernel.org, hannes@cmpxchg.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, mhocko@kernel.org, muchun.song@linux.dev, roman.gushchin@linux.dev, syzkaller-bugs@googlegroups.com, zhengqi.arch@bytedance.com, yosry@kernel.org Subject: Re: [syzbot] [mm?] [cgroups?] WARNING: bad unlock balance in lruvec_stat_mod_folio Message-ID: References: <69d54494.050a0220.3030df.0002.GAE@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <69d54494.050a0220.3030df.0002.GAE@google.com> X-Migadu-Flow: FLOW_OUT +Qi & Yosry On Tue, Apr 07, 2026 at 10:53:24AM -0700, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: cc13002a9f98 Add linux-next specific files for 20260402 > git tree: linux-next > console output: https://syzkaller.appspot.com/x/log.txt?x=10d8946a580000 > kernel config: https://syzkaller.appspot.com/x/.config?x=4e6c8be618ab359 > dashboard link: https://syzkaller.appspot.com/bug?extid=1a3353a77896e73a8f53 > compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8 > > Unfortunately, I don't have any reproducer for this issue yet. Let's wait for the reproducer. I can only think of cgroup_subsys_on_dfl() check returning different value in get_non_dying_memcg_start() and get_non_dying_memcg_end() to cause this uneven rcu unlock. However I can't think why and how that can happen.