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Date: Tue, 18 Aug 2026 12:42:54 -1000
From: Tejun Heo <tj@kernel.org>
To: Ziyang Men <ziyang.meme@gmail.com>
Cc: kernel-team@meta.com, Jens Axboe <axboe@kernel.dk>,
	Josef Bacik <josef@toxicpanda.com>,
	Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	Andrii Nakryiko <andrii@kernel.org>,
	Eduard Zingerman <eddyz87@gmail.com>,
	Kumar Kartikeya Dwivedi <memxor@gmail.com>,
	Martin KaFai Lau <martin.lau@linux.dev>, Song Liu <song@kernel.org>,
	Yonghong Song <yonghong.song@linux.dev>,
	Jiri Olsa <jolsa@kernel.org>,
	Emil Tsalapatis <emil@etsalapatis.com>,
	Shuah Khan <shuah@kernel.org>, Johannes Weiner <hannes@cmpxchg.org>,
	Michal =?iso-8859-1?Q?Koutn=FD?= <mkoutny@suse.com>,
	Roman Gushchin <roman.gushchin@linux.dev>,
	Shakeel Butt <shakeel.butt@linux.dev>,
	JP Kobryn <inwardvessel@gmail.com>,
	Mykola Lysenko <mykolal@meta.com>, linux-block@vger.kernel.org,
	bpf@vger.kernel.org, cgroups@vger.kernel.org,
	linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/2] block: add BPF kfuncs to read blkcg io.stat
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On Tue, Aug 18, 2026 at 03:31:29PM -0700, Ziyang Men wrote:
> Ok I will add the casts bpf_get_blkcg() and bpf_put_blkcg(), and remove the
> check of css->ss in above functoins.

RCU_PROTECTED is probably better than get/put().

Thanks.

-- 
tejun