From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 10F0C3B3C03; Thu, 13 Aug 2026 09:27:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786613254; cv=none; b=O5YD3crj6XtY/BaKyZLZBdxioAgMIZ/LQQAQTmFi4R2NGeAcqckftoK5nzlbAzOcSjd/JnBP57V/Pq3Uuts3ESxN1Yv4QItlGOnrxJPoa1YdhzH4HMjGr/6iEgT3UCnDjGKmKcNBU39gnYhWtUYYzw0WnMryx/8zwpYErHrFF8s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786613254; c=relaxed/simple; bh=EKKHgSs8yZh6+u9oH06JQBe1jVKZ/DCCbiTqpOIy7QM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=n0WjLrLO1bfoehC4CVYjeigzz6C2pNJHqrjxH6tBePPTIrXswAJ4jzG7cywZhah1kBpV1vjrMjCnfOji+qeFlV2XNvNLzkUWUayJiw8S06Yf65f88h50q2pWxzjjcEneoCxS+HYqz/vH5t/MsacTYOvoYMundwoeT0fPo1IKCiE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=fKKP0aaf; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="fKKP0aaf" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7E3771F00A3A; Thu, 13 Aug 2026 09:27:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786613250; bh=J0WfG9LtUU7qIATkbY9c7VbNU4tFX7Iam6iBGsEbqBM=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=fKKP0aaflcesVE16gmCdIUQZXRadXKPNnorPID/XlTMeQNeLHsIR28CRvP+c6tv0J GiCgXFFIpH2jQffDALJEoRKtEpNvFEK/wsgTFqXso/t6JYdOaw2xjsePWdkwspBvrk LAcdnbsVjFw2Rq9h4BiQ69Sk4X/EaJA7hQhJhbvTOuMR9DA8JqwLBB99tjjrjz34o6 D8XYz0iZ4U515IRFaGmbyVSZ6WyRGrmMhaMfYv25FKZTceSb2wGwabvOSN6HmubtGj ND6iPTXtl32xcMeLHue7tZns05qcKFHWgznrw+8cFKUft+K5WGYP2xuRtxkRyswykU 0DapLWAEcv6qQ== Date: Thu, 13 Aug 2026 10:27:09 +0100 From: "Lorenzo Stoakes (ARM)" To: Shakeel Butt Cc: Andrew Morton , Michal Hocko , Johannes Weiner , Roman Gushchin , Muchun Song , David Hildenbrand , 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] > > 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(-) This is a gorgeous diffstat :) Obviously not my area but looking over it, all LGTM so feel free to add: Acked-by: Lorenzo Stoakes (ARM) To the whole series! > > -- > 2.53.0-Meta > -- Cheers, Lorenzo