From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr1-f54.google.com (mail-wr1-f54.google.com [209.85.221.54]) (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 ED7081D6AA for ; Mon, 28 Jul 2025 10:44:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.54 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753699462; cv=none; b=NgDeyQ9DnfKnWU+DOlWaR/ks3Cv7Mrk0izfV4ElTMaJ1c37QoCf7ZJs3p05YaXymdc8EWHweYy/G8vZgdlZwny5Gzko0yvypUslPxxHww+dhRQOuXs5+OaqYkrps9JG9mJdQc8CflaECBKERiNsxiZlxa0Gg1OzT5HWwcMsJZF0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753699462; c=relaxed/simple; bh=a68dC2IX5RZYA7JVsZSDy7V2bCDDXQ+0qW4mqbUTXe4=; h=Message-ID:Date:MIME-Version:Subject:To:References:From: In-Reply-To:Content-Type; b=QgoYD0qReh/L9uBhOdvsE5VfYqOdDfTcCymNXyb3GHcSRHnJ8dSrcYv0ddDe/fAop7lQ366X9Yd91W6RmuNIf1R6ayKo/iOQUDNyZSl2W1AU+ovDe84dU/lcyCxOVNvu4WHIxJNYypph6MYDXkgWL9lveW7l1wb1F/YiURXF9Tg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com; spf=pass smtp.mailfrom=suse.com; dkim=pass (2048-bit key) header.d=suse.com header.i=@suse.com header.b=UUaeSnao; arc=none smtp.client-ip=209.85.221.54 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=suse.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=suse.com header.i=@suse.com header.b="UUaeSnao" Received: by mail-wr1-f54.google.com with SMTP id ffacd0b85a97d-3b78bca0890so189955f8f.3 for ; Mon, 28 Jul 2025 03:44:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1753699458; x=1754304258; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:autocrypt:from :content-language:references:to:subject:user-agent:mime-version:date :message-id:from:to:cc:subject:date:message-id:reply-to; bh=AQi3D0BOdiwNH4O7hK3zflxmgiJZgaFAAv8Hugio95o=; b=UUaeSnaotH6K52Nio2Yd5Onz1mc82Ds99W6SKr3RsCGo2Bb5RSS0ckWMup4/EGoz7A AkMgE4IYboiW67VcsqnJLPT5i0p0mtd5Ga2vOVmRjhhlt3Vv9NCUFbZZIWE9eBdQ8PNA yFeZPo8c+7yvbJcFSNi5YFnfGbv5kug6r7BeLEDkxA0Rwtq1ZHUbLfo5QtgZiLqP/scN Up/wNpiUpbJ4KfjYVXY9XipuR1/PXtazVDyZlqV/ZNz866Fk4dGfZ52fsgP1PVfLMIQt /tt8cGK92U3Cki2Rd6fXeeI8dnql45PQHZbFGsAsH8r8dnoL4+UJJ5+wdKymDLX6sivG PUNQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1753699458; x=1754304258; h=content-transfer-encoding:in-reply-to:autocrypt:from :content-language:references:to:subject:user-agent:mime-version:date :message-id:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=AQi3D0BOdiwNH4O7hK3zflxmgiJZgaFAAv8Hugio95o=; b=PrILQYWfk1lB+o5u5WqGMPLuLHcr0yerqanfy+kdUKfY5hQo3TmoHrtyRZXtneDWtq XoGG2Sjy9wENF/S32KZ4RIKk001P78DKd3wKpXY32fr1/aDISakUozaAKq9kpUFS24LT Zu1dJ053noErtSwj+v+Z3WpSMxiddK1vybewdCmKKAmlhHuLxa3MPB5iIZpddjsfMSPQ jcgRXWxzrLltfmnRhyWSbmYahgn5TIGt/iB60OXViGJo3pqvPZoJNN7JNyjugugVNa+/ PpAZ1wKxE04b83vwo0Pi2Q7HuUIsksrtlhOvok1yhVExwOBPeAj08TASoUZDvkzFJzl9 VOHw== X-Gm-Message-State: AOJu0Yz6HCFMBSi1K9nICGWhRWJL+fslHoVLeZVRh5/fdNxGBvxqN8KH 6Ox3DoNIvuaxc/5lgxmhL2sj4beN11IURjSpqIhgsEdFJVOqtWTMwU+nc3KMayMs65RCNtHQ+4f Gk7FG X-Gm-Gg: ASbGncvw2Lltm3hBHib6l4eqY70SWb96UtrdkEQKUVnVwRlaDhWN0a1XrcCZENUKJ2Y jB7OImRL6cKF0fIGDtA1fBAVi5p6c5PF6uSKeO6SnWYTZjJVhdBeiQ9esW5w9SDznhzzWwL4tzh z9zRUtsMDZLCzWrkvykVOVWK1gCEqDPH8Zwk3hyl0aYaW0hZhxKAyyGo3r76zERtQuzVHLVdqbS nkjhIT5dUkAaP1HAW53W4kfjiwHDC9sR0FErMtRVDQRiFtGDLZLqtjFiK2fPQ6J1QzNZpszc4Zb 3Z6NBC4Ss01kSBK/i5UA6CBidsTAHNcYjZ/2C6xLq0RY9P0De0deTtwa5fynOcSjfqpvTjQWJ0u Rk6lnVrP5h/phjT8zpqLRKKpVcFsBUqMsYtuMauduGYiA+7WA9WNFlfQaxkmL X-Google-Smtp-Source: AGHT+IEtIiJ41reXLFCk7CoFIT8yNe/+mOZd+j0LlzrV1QWrmTmc5stNjbFP5X2jbRf7XwUfIgdLHQ== X-Received: by 2002:a05:6000:2284:b0:3a4:f520:8bfc with SMTP id ffacd0b85a97d-3b77675ff55mr8608562f8f.36.1753699458034; Mon, 28 Jul 2025 03:44:18 -0700 (PDT) Received: from ?IPV6:2403:580d:fda1::299? (2403-580d-fda1--299.ip6.aussiebb.net. [2403:580d:fda1::299]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-23fbe571756sm51980015ad.195.2025.07.28.03.44.16 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 28 Jul 2025 03:44:17 -0700 (PDT) Message-ID: <2099a2c0-2977-4ecb-8276-a878fe17ab24@suse.com> Date: Mon, 28 Jul 2025 20:14:14 +0930 Precedence: bulk X-Mailing-List: linux-btrfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: cannot read default subvolume id? To: linux-btrfs References: <20250727174618.GD842273@tik.uni-stuttgart.de> <20250728100845.GE842273@tik.uni-stuttgart.de> Content-Language: en-US From: Qu Wenruo Autocrypt: addr=wqu@suse.com; keydata= xsBNBFnVga8BCACyhFP3ExcTIuB73jDIBA/vSoYcTyysFQzPvez64TUSCv1SgXEByR7fju3o 8RfaWuHCnkkea5luuTZMqfgTXrun2dqNVYDNOV6RIVrc4YuG20yhC1epnV55fJCThqij0MRL 1NxPKXIlEdHvN0Kov3CtWA+R1iNN0RCeVun7rmOrrjBK573aWC5sgP7YsBOLK79H3tmUtz6b 9Imuj0ZyEsa76Xg9PX9Hn2myKj1hfWGS+5og9Va4hrwQC8ipjXik6NKR5GDV+hOZkktU81G5 gkQtGB9jOAYRs86QG/b7PtIlbd3+pppT0gaS+wvwMs8cuNG+Pu6KO1oC4jgdseFLu7NpABEB AAHNGFF1IFdlbnJ1byA8d3F1QHN1c2UuY29tPsLAlAQTAQgAPgIbAwULCQgHAgYVCAkKCwIE FgIDAQIeAQIXgBYhBC3fcuWlpVuonapC4cI9kfOhJf6oBQJnEXVgBQkQ/lqxAAoJEMI9kfOh Jf6o+jIH/2KhFmyOw4XWAYbnnijuYqb/obGae8HhcJO2KIGcxbsinK+KQFTSZnkFxnbsQ+VY fvtWBHGt8WfHcNmfjdejmy9si2jyy8smQV2jiB60a8iqQXGmsrkuR+AM2V360oEbMF3gVvim 2VSX2IiW9KERuhifjseNV1HLk0SHw5NnXiWh1THTqtvFFY+CwnLN2GqiMaSLF6gATW05/sEd V17MdI1z4+WSk7D57FlLjp50F3ow2WJtXwG8yG8d6S40dytZpH9iFuk12Sbg7lrtQxPPOIEU rpmZLfCNJJoZj603613w/M8EiZw6MohzikTWcFc55RLYJPBWQ+9puZtx1DopW2jOwE0EWdWB rwEIAKpT62HgSzL9zwGe+WIUCMB+nOEjXAfvoUPUwk+YCEDcOdfkkM5FyBoJs8TCEuPXGXBO Cl5P5B8OYYnkHkGWutAVlUTV8KESOIm/KJIA7jJA+Ss9VhMjtePfgWexw+P8itFRSRrrwyUf E+0WcAevblUi45LjWWZgpg3A80tHP0iToOZ5MbdYk7YFBE29cDSleskfV80ZKxFv6koQocq0 vXzTfHvXNDELAuH7Ms/WJcdUzmPyBf3Oq6mKBBH8J6XZc9LjjNZwNbyvsHSrV5bgmu/THX2n g/3be+iqf6OggCiy3I1NSMJ5KtR0q2H2Nx2Vqb1fYPOID8McMV9Ll6rh8S8AEQEAAcLAfAQY AQgAJgIbDBYhBC3fcuWlpVuonapC4cI9kfOhJf6oBQJnEXWBBQkQ/lrSAAoJEMI9kfOhJf6o cakH+QHwDszsoYvmrNq36MFGgvAHRjdlrHRBa4A1V1kzd4kOUokongcrOOgHY9yfglcvZqlJ qfa4l+1oxs1BvCi29psteQTtw+memmcGruKi+YHD7793zNCMtAtYidDmQ2pWaLfqSaryjlzR /3tBWMyvIeWZKURnZbBzWRREB7iWxEbZ014B3gICqZPDRwwitHpH8Om3eZr7ygZck6bBa4MU o1XgbZcspyCGqu1xF/bMAY2iCDcq6ULKQceuKkbeQ8qxvt9hVxJC2W3lHq8dlK1pkHPDg9wO JoAXek8MF37R8gpLoGWl41FIUb3hFiu3zhDDvslYM4BmzI18QgQTQnotJH8= In-Reply-To: <20250728100845.GE842273@tik.uni-stuttgart.de> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit 在 2025/7/28 19:38, Ulli Horlacher 写道: > On Mon 2025-07-28 (08:06), Qu Wenruo wrote: >> >> >> 圚 2025/7/28 03:16, Ulli Horlacher 写é": >> >>> >>> Why is there a "cannot read default subvolume id"? >>> >>> tux@quak:~: btrfs sub create xx >>> Create subvolume './xx' >>> >>> tux@quak:~: btrfs sub del xx >>> WARNING: cannot read default subvolume id: Operation not permitted >> >> It's a warning, not an error. And you can see on the next line, the >> deletion happened without any problem. > > But this warning confuses a user: > Is there a problem? > What is going wrong? > Have I made a mistake? Yes, that's indeed confusing, and it should be hidden by commit 0e66228959c4 ("btrfs-progs: subvol delete: hide a warning on an unprivileged delete"), which is included in v5.16. Unfortunately that fix has a bug that the uid check is completely opposite... > >> You're running as a non-root user, meanwhile default subvolume id search >> is done using tree search ioctl, which require root privilege. > > Why is this subvolume id search necessary for subvolume deletion and why > is it just a warning and apparently no problem at all? > If it does not have any consequences, it should not be displayed. > It is an extra check to output a more meaningful error message if the end user is trying to delete the default subvolume. Thus we need to search if the current subvolume is a default one. Thanks, Qu