From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta1.migadu.com (out-70.mta1.migadu.com [95.215.58.70]) (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 38C8432F749 for ; Sat, 29 Aug 2026 03:13:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.70 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787973227; cv=none; b=bCx4xophmafK+ytFM8d5vPoxfH0d3yrTTuQh3DZ90e6r1pPPtt3xw0/UqkyUhbLc4MWmu6P/ShnZDdFQMTqX5xhNzbb7qU0Ppgbvysm6ItMA4kXei+96QYwfnA2uM20rzXxal/7sOLYV07p1qSo1HJUotLYGXEHpvmpI9u/xOmo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787973227; c=relaxed/simple; bh=cDW6ej3nsOtAs9UhYM6om1L/1lvDe6jcM4V1q9Oa8bw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=crlM2M4NzwC2ttEXMcqfKA4tMts7RUVSHvbNazgTGxkTLZCuFE+mFlVFFokl1+exORmU65K7Lv8iq4Ipn2nKt4MItc0BmAOlpEMfmIJLhSFRX/FP6/GMXgdGgzLzlp6gJG7+YIQvO9l+qjXG7UwMgqHcq0KYQHJT8DJINkEEU98= 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=aZLBTCbX; arc=none smtp.client-ip=95.215.58.70 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="aZLBTCbX" X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=cDW6ej3nsOtAs9UhYM6om1L/1lvDe6jcM4V1q9Oa8bw=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1787973223; v=1; x=1788578023; b=aZLBTCbXkU7d/zoBiSkVOZ78BoDyWbRzDyQh1tkWdy4wjUXmdrdbiy2oZ/wr3B6PZg2VgGon W9cXn+PfriyEh2EkV4myEHx0XS9mc7u+7hz2s/AYLpqomFxJU218OHYdfpItrPR3ztXMht0Vgom d6AlUFpCOevcXhCKxZEhiuRY= X-Envelope-To: linux-kernel@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id 6e5a30d5d232ca82; Sat, 29 Aug 2026 03:13:32 +0000 X-Mizu-Trace-ID: 6e5a30d5d232ca82 X-Migadu-Flow: FLOW_OUT Date: Fri, 28 Aug 2026 20:13:31 -0700 From: Shakeel Butt To: Andrew Morton Cc: Michal Hocko , Johannes Weiner , Roman Gushchin , Muchun Song , David Hildenbrand , Lorenzo Stoakes , Kairui Song , Qi Zheng , Barry Song , Axel Rasmussen , Meta kernel team , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH for-7.4 0/9] memcg: remove the v1 soft limit Message-ID: References: <20260811203203.3456029-1-shakeel.butt@linux.dev> <20260828194322.0556dcbd1c261c23a1f6efec@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: <20260828194322.0556dcbd1c261c23a1f6efec@linux-foundation.org> On Fri, Aug 28, 2026 at 07:43:22PM -0700, Andrew Morton wrote: > On Fri, 28 Aug 2026 19:23:19 -0700 Shakeel Butt wrote: > > > On Tue, Aug 11, 2026 at 01:31:54PM -0700, Shakeel Butt wrote: > > > Syzbot reported [1] a set_mm_walk() warning from kswapd. Soft limit > > > reclaim is the only thing that runs shrink_lruvec() from kswapd with a > > > target memcg set, and thus the only way kswapd can reach > > > lru_gen_shrink_lruvec() and in turn set_mm_walk(). The offender, > > > mem_cgroup_shrink_node(), has long carried a "Only used by soft limit > > > reclaim. Do not reuse for anything else." comment and a priority hack, > > > and it simply never got taught about MGLRU. > > > > > > Rather than teach it, let's delete it. The v1 soft limit was deprecated > > > in v6.12 by commit 569c4f62d84a ("memcg: initiate deprecation of v1 > > > soft limit"). Nobody has reported depending on it in the ~21 months > > > since, and v2 has covered the same ground for a long time with > > > memory.low and memory.min. > > > > > > Link: https://lore.kernel.org/all/6a7a6929.b50370da.49fe0.005e.GAE@google.com/ [1] > > > > Andrew, should I resend this series (without the first patch) or will you pick > > it up? > > I added the series, thanks. > > The [1/9] has already been queued in mm-hotfixes as a backportable > hotfix. So I added it as an 8-patch series. Because of this the cover > letter of that series is now irrelevant, so could you please prepare a > brief replacement for me to paste in? > > Sashiko suggests that there's more that can be removed: > https://sashiko.dev/#/patchset/20260811203203.3456029-1-shakeel.butt@linux.dev > > So maybe an 8-patch v2 series is appropriate, your call. I will send 8-patch v2 series with Sashiko's comments resolved by next week.