From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta1.migadu.com (out-2.mta1.migadu.com [95.215.58.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 62D35354AEB for ; Wed, 12 Aug 2026 21:41:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.2 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786570918; cv=none; b=AI5L5IoxSXmcXOuK5f/J6cgjaBIVkNJe43HLzjaeItHhxMdcR9Is90bgb0HmUqChWnaZ5tjfDXJfXoKp7CefQDjiszql7hDm3GDarMFhk5y2hoOtERk6q/DPR4qYHlLr8ICn9hfi58FAtZI2sYzvJj7CyOeoKlmtiRA2y9wWBo4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786570918; c=relaxed/simple; bh=2F5NhUpezBCQsHKeIjnstp2S/raV+rcTxDfwPc9Xn34=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=HYhwsCE+bFSoauZcYChf6PkcIM9N3EtZACyp4X4dlZPf7hLrGkYRPATijrOkIO9YPobaEYTMgBx6KQHlFCu6RoW+Ae9SFJToWSufP1zIlpKrTsihT00INgvY6VLfwG+VMMhEFS2mXa7YdeaXutVu9/reNC8rJUK+ZGQ8uow0MUc= 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=eM67pAkU; arc=none smtp.client-ip=95.215.58.2 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="eM67pAkU" X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=2F5NhUpezBCQsHKeIjnstp2S/raV+rcTxDfwPc9Xn34=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1786570914; v=1; x=1787175714; b=eM67pAkUUhF8/me/ldGi3bvDUWGNU1Pd9opNRMcS+ebTYCsoa3RarEcx+NjIVgRds9QYw0QL TKPCEmIKLwRZ5RsUTyFMoJdJnyS5/k360fnv4pmha4VxLR/F1Bmii8G8po19QfbzDOqSlN0UqIo 02kz2Dfcqvc84NTYdbHL4JGE= X-Envelope-To: linux-kernel@vger.kernel.org Received: from localhost (2a03:2880:10ff:48::) by smtp.migadu.com with ESMTPS id d28f7b4220e49d71; Wed, 12 Aug 2026 21:41:54 +0000 X-Migadu-Flow: FLOW_OUT Date: Wed, 12 Aug 2026 14:41:49 -0700 From: Shakeel Butt To: Andrew Morton Cc: syzbot , axelrasmussen@google.com, baohua@kernel.org, baolin.wang@linux.alibaba.com, cgroups@vger.kernel.org, david@kernel.org, hannes@cmpxchg.org, kasong@tencent.com, kernel-team@meta.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, ljs@kernel.org, mhocko@kernel.org, mhocko@suse.com, muchun.song@linux.dev, qi.zheng@linux.dev, roman.gushchin@linux.dev, syzkaller-bugs@googlegroups.com, weixugc@google.com, yuanchu@google.com Subject: Re: [syzbot] [mm?] WARNING in set_mm_walk Message-ID: References: <6a7a6929.b50370da.49fe0.005e.GAE@google.com> <6a7c6670.3668565d.e8814.0012.GAE@google.com> <20260812140358.343927ad8d0955b67c4e7ad5@linux-foundation.org> 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: <20260812140358.343927ad8d0955b67c4e7ad5@linux-foundation.org> On Wed, Aug 12, 2026 at 02:03:58PM -0700, Andrew Morton wrote: > On Wed, 12 Aug 2026 05:26:24 -0700 syzbot wrote: > > > syzbot has found a reproducer for the following issue on: > > > > HEAD commit: f5bbbfec59b4 Merge tag 'probes-fixes-v7.2-rc7' of git://gi.. > > git tree: upstream > > console output: https://syzkaller.appspot.com/x/log.txt?x=11f44c79580000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=c44651ea7dd2f307 > > dashboard link: https://syzkaller.appspot.com/bug?extid=12ee2725d5fde63a9c96 > > compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10d11149580000 > > > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > > Reported-by: syzbot+12ee2725d5fde63a9c96@syzkaller.appspotmail.com > > > > ------------[ cut here ]------------ > > current_is_kswapd() > > WARNING: mm/vmscan.c:3800 at set_mm_walk+0x210/0x270 mm/vmscan.c:3800, CPU#2: kswapd0/111 > > Thanks. Shakeel is working on a series which will fix this by removing > the calling code. But it isn't a minor patch. > > Shakeel, it would be good to have a backportable quick-fix to make this > warning go away? > Actually the first patch [1] of the series will fix this warning and we can backport just that patch to the older stable kernels. Do you want me to send that patch as a standalone? [1] https://lore.kernel.org/all/20260811203203.3456029-2-shakeel.butt@linux.dev/