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 1E640282F1B; Thu, 1 Oct 2026 00:21:00 +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=1790814062; cv=none; b=J5Ag5XBzLA887aWmZKVCtGwWsa1WudeeYS8RPguPge9JUyv/JhBZMPzfPhP1szlg4gv+Bid+D5Xt5ctkj2d7eIjnWPBKST4voXJBJpnNdYXfZ3tstRwoE7LlSEYMyhuFCZJMCCZBNB7JeVWlr7yk3Yt6YDVkp9Za7jxu4NTT/6s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790814062; c=relaxed/simple; bh=zeHVgwVQCOpZGPbuV62NoIgPlJtExvO0see6x6+V+ec=; h=Date:Message-ID:From:To:Cc:Subject:In-Reply-To:References; b=mmF8kauLNSP877v143hYGcrMHJBGvvqYft2H5cL1fzWCFB8nq4w2jV3haU4NFjU2z7NOtPWfWeIX73V3s0PrMTF7sJDfIAmr10Oac9FynIRbPXOtV/y17/vkf3c/PgD3qf17M37/Liv7nLPO9fGAKUW/yx2eKKzvJuZMf/zqMpQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=A1qlvmsR; 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="A1qlvmsR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6E5E41F000FF; Thu, 1 Oct 2026 00:21:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790814060; bh=MewAlD5aSkZUtyyg83a3AwFjqYwD/VRSwZs4SdrxEIc=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=A1qlvmsRclnrJENovY2lSglSpAReArBZURRYsuf4IzM2ie8lBU4QaR9U2gTdTDk00 Py74PGm/smkybm+uisQp0IV8VAz+kho6nxbfxumWCTAwbNFVLge6nNt6TZIsueX8bN VM6zN6NnSQLLaIVkTKO0jYiZiJQO8c2AA5bX3D9uqHeshq31NsR42dJC0ZQ7CDrw8B MFFCvEsqLHONsYb2e71Vd+oh2SHTgJnOR9ygMTByMGMY+nUfTxHhB9PBg1bLVkuRYE R8kfElHV8KJ4rQ6t+Xi5qMSut+ZpcfdEL7RI/tnZNl3N8WgRlw0N47ametf57apq3r kbS0joADhj0Eg== Date: Wed, 30 Sep 2026 14:20:59 -1000 Message-ID: <95edaf582303f1a9404c989f9f0e6501@kernel.org> From: Tejun Heo To: Tao Cui Cc: josef@toxicopanda.com, axboe@kernel.dk, cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, andrii@kernel.org, eddyz87@gmail.com, ast@kernel.org, daniel@iogearbox.net, linux-kselftest@vger.kernel.org, Tao Cui , ameryhung@gmail.com, alexei.starovoitov@gmail.com Subject: Re: [RFC PATCH v8 4/4] docs: cgroup-v2: document the iocost BPF cost model attachment In-Reply-To: <20260930075154.189958-5-cui.tao@linux.dev> References: <20260930075154.189958-1-cui.tao@linux.dev> <20260930075154.189958-5-cui.tao@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Hello, Tao. The following is a Claude-generated review. On Wed, 30 Sep 2026 15:51:54 +0800, Tao Cui wrote: > + When CONFIG_BLK_CGROUP_IOCOST_BPF is enabled, a BPF cost model > + can be attached to a device by loading an "iocost_model_ops" > + struct_ops with the whole disk's major:minor in its "dev" member ... > + switches back to the builtin model, and neither detaches the > + struct_ops; only detaching removes the model, after which > + "model=bpf" fails. "ctrl" keeps describing the builtin Attaching, not loading, binds the model. The test loads a second model fine and only its attach fails. Device removal also removes the model, and the user still has to tear down the struct_ops link afterwards. Can you mention that too? Thanks. -- tejun