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Date: Tue, 10 Sep 2024 10:03:57 -1000
From: Tejun Heo <tj@kernel.org>
To: Michal =?iso-8859-1?Q?Koutn=FD?= <mkoutny@suse.com>
Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-mm@kvack.org, Zefan Li <lizefan.x@bytedance.com>,
	Johannes Weiner <hannes@cmpxchg.org>,
	Michal Hocko <mhocko@kernel.org>,
	Roman Gushchin <roman.gushchin@linux.dev>,
	Shakeel Butt <shakeel.butt@linux.dev>,
	Muchun Song <muchun.song@linux.dev>,
	Andrew Morton <akpm@linux-foundation.org>,
	Chen Ridong <chenridong@huawei.com>
Subject: Re: [PATCH 3/4] cgroup: Disallow mounting v1 hierarchies without
 controller implementation
Message-ID: <ZuCmLXMLQd7xMs06@slm.duckdns.org>
References: <20240909163223.3693529-1-mkoutny@suse.com>
 <20240909163223.3693529-4-mkoutny@suse.com>
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In-Reply-To: <20240909163223.3693529-4-mkoutny@suse.com>

On Mon, Sep 09, 2024 at 06:32:22PM +0200, Michal Koutný wrote:
> The configs that disable some v1 controllers would still allow mounting
> them but with no controller-specific files. (Making such hierarchies
> equivalent to named v1 hierarchies.) To achieve behavior consistent with
> actual out-compilation of a whole controller, the mounts should treat
> respective controllers as non-existent.
> 
> Wrap implementation into a helper function, leverage legacy_files to
> detect compiled out controllers. The effect is that mounts on v1 would
> fail and produce a message like:
>   [ 1543.999081] cgroup: Unknown subsys name 'memory'
> 
> Signed-off-by: Michal Koutný <mkoutny@suse.com>

Applied to cgroup/for-6.12.

Thanks.

-- 
tejun