From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta1.migadu.com (out-1.mta1.migadu.com [95.215.58.1]) (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 24C77282F30 for ; Sat, 29 Aug 2026 02:23:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.1 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787970207; cv=none; b=YnZJO+365A6B0y6VzTYnYiefHlzC9surmRTpPw9pbWt36qqXTH1lt0JgAS+nfU3k8E1Q6j+j4o7snUPFLw6CvYzm+K2DaOc4F7C90gOzk6vERsqBzpY2uUjElm+0rQTudFihkSr6rBoniZPH6HGE8rkpJhfzAWV3bDI/tQFdUh0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787970207; c=relaxed/simple; bh=9dpmGVCTK6YIdLHcSKf21OYzQ3WaSDmWbAA1Hj8B9Aw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=cutZlvKDgsc5/NCH6MuO8QqtDMQ8DFo2QbTtLkMpbWLxh+vTb+3bqt/y/5XOwynE2J53fj4zL/6gxsxVT8KzEUJH5Cyi22HLJZ7Z10qJCMUty0K7Rdm7B8EQ83K9kZfN9cD75ILj/F0rqLVv2IwI8Dy/nkN1bV8+T9fLHAMWC/I= 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=BJB2b2UL; arc=none smtp.client-ip=95.215.58.1 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="BJB2b2UL" X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=9dpmGVCTK6YIdLHcSKf21OYzQ3WaSDmWbAA1Hj8B9Aw=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1787970201; v=1; x=1788575001; b=BJB2b2ULznAVmp1DP0FBgu/aMBBbQLjTBZ9MctHHmOjry8gZNls4HyFKlXx+r2gJKN67GTRw FSbskbvGJNKp8MRRTYpWMas251B9NOecy8deGS1PMb6n86GzFFjteGr1GjTqBCvn7lBeuezNaoz 8TCSqOZlswsD2pjHAexik4Tw= X-Envelope-To: linux-kernel@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id 167889d1c3b5653f; Sat, 29 Aug 2026 02:23:21 +0000 X-Mizu-Trace-ID: 167889d1c3b5653f X-Migadu-Flow: FLOW_OUT Date: Fri, 28 Aug 2026 19:23:19 -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> 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: <20260811203203.3456029-1-shakeel.butt@linux.dev> 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? > > Shakeel Butt (9): > memcg: make the v1 soft limit knob inert > memcg: remove v1 soft limit reclaim > memcg: remove mem_cgroup_shrink_node() > memcg: remove the soft limit reclaim tracepoints > memcg: remove the soft limit rbtree > memcg: remove lru_gen_soft_reclaim() > memcg: remove the per-node soft limit tree fields > memcg: remove mem_cgroup->soft_limit > memcg: simplify v1 event ratelimiting > > .../admin-guide/cgroup-v1/memory.rst | 49 +- > include/linux/memcontrol.h | 27 -- > include/linux/mmzone.h | 30 +- > include/trace/events/vmscan.h | 14 - > mm/internal.h | 4 - > mm/memcontrol-v1.c | 435 ++---------------- > mm/memcontrol-v1.h | 12 +- > mm/memcontrol.c | 7 +- > mm/vmscan.c | 96 +--- > 9 files changed, 66 insertions(+), 608 deletions(-) > > -- > 2.53.0-Meta >