From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 1507D77F0A; Tue, 12 Mar 2024 08:47:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710233278; cv=none; b=FDtTJOdkVn90V+P/2dRqVEV67wkQ471IykrA+MQHo5IyKx8tpBP1oavz/e2hwjStOinmFL8gILTVRCRyBZM5sxIyBRTESIjECqSdiIW3Vm9D8M2saUIvkdgdfPFhGhJvHHEJVeRdY8TMVuTLa8YNY5vwkvbAm9NIMND6bv5PZ/c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710233278; c=relaxed/simple; bh=USx0cA5m8QHpw1Pr8TQY0RJPdw62miN7yco5K9ORroc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ErcfkoKr2o70Jkbr6FOA6bK/zNJt0b7UzIr30VCFAQ2xIGsrW2lz3/TTlJZc8TSa/L2F2L21Gddl/y5b8n4QW0N+WJp1G/JOP8BE8odr8yiXjiEVXmbaUGyPlXfvg88M/1hv/ZoJo9TKk/O1Xk46OxPmdUR42Q4ZZYdNIu+cSTA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=EWAKYj9H; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="EWAKYj9H" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D66D3C433F1; Tue, 12 Mar 2024 08:47:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1710233277; bh=USx0cA5m8QHpw1Pr8TQY0RJPdw62miN7yco5K9ORroc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=EWAKYj9H+Jl9xOXothDdY5tMH9XlzGG4elGZJeXi/nnLM/yVM/KEmOdv2iDrF/Urz 66jfhi5uf2BQm1imtI3BPT/Rdt0h1eP00J6xHGyNpbJgjqXrcvx18qyh270VBRWddy lFh5TtVBKFUusVgjEyO5JVaEaE+LChqLJzoF+zSeas7zXX7jtgZWhg7y3Ojj4RwHmt jrwzieTtOKzCXv4pE0qCqQW9EU4MNb1jWTG/8hzGK3XmkLuNelSUUNh5Qm52Z65N1V tDH8K20rvOnEr96pQJV1W8ncB3+Oh8lbJK6qvBCzfQEA5wRE40OzA/5YWBrwkKGmmc PUoY8wqM/HY4g== Date: Tue, 12 Mar 2024 09:47:52 +0100 From: Christian Brauner To: Miklos Szeredi Cc: Luis Henriques , Theodore Ts'o , Andreas Dilger , Alexander Viro , Jan Kara , Amir Goldstein , linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-unionfs@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 3/3] ovl: fix the parsing of empty string mount parameters Message-ID: <20240312-orten-erbsen-2105c134762e@brauner> References: <20240307160225.23841-1-lhenriques@suse.de> <20240307160225.23841-4-lhenriques@suse.de> <87le6p6oqe.fsf@suse.de> <20240311-weltmeere-gesiegt-798c4201c3f8@brauner> Precedence: bulk X-Mailing-List: linux-ext4@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On Mon, Mar 11, 2024 at 03:39:39PM +0100, Miklos Szeredi wrote: > On Mon, 11 Mar 2024 at 14:25, Christian Brauner wrote: > > > Yeah, so with that I do agree. But have you read my reply to the other > > thread? I'd like to hear your thoughs on that. The problem is that > > mount(8) currently does: > > > > fsconfig(3, FSCONFIG_SET_FLAG, "usrjquota", NULL, 0) = -1 EINVAL (Invalid argument) > > > > for both -o usrjquota and -o usrjquota= > > For "-o usrjquota" this seems right. > > For "-o usrjquota=" it doesn't. Flags should never have that "=", so > this seems buggy in more than one ways. > > > So we need a clear contract with userspace or the in-kernel solution > > proposed here. I see the following options: > > > > (1) Userspace must know that mount options such as "usrjquota" that can > > have no value must be specified as "usrjquota=" when passed to > > mount(8). This in turn means we need to tell Karel to update > > mount(8) to recognize this and infer from "usrjquota=" that it must > > be passed as FSCONFIG_SET_STRING. > > Yes, this is what I'm thinking. Of course this only works if there > are no backward compatibility issues, if "-o usrjquota" worked in the > past and some systems out there relied on this, then this is not > sufficient. Ok, I spoke to Karel and filed: https://github.com/util-linux/util-linux/issues/2837 So this should get sorted soon. > > https://github.com/brauner/man-pages-md/blob/main/fsconfig.md > > What's the plan with these? It would be good if "man fsconfig" would > finally work. Yeah, I have this on my todo list but it hasn't been high-prio for me and it is just so so nice to update the manpages in markdown.