From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 0D80935953; Mon, 9 Dec 2024 13:45:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733751912; cv=none; b=O1OHzva6HkeK4oXCiN6dN5BpcO6FdUeFfZjLcDEu97OtYmned24ANVk8Azv1ha4geUnyw2werveeXc7d41nnFibSBsnw46N5w8twdsRf4nBF99+gjm509tTkV0ROz+DrkHO2WELTR9KcuDmAjF8OAKFnV3iBGXc/TQ23++j9nnw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733751912; c=relaxed/simple; bh=1a6G46JfjtTX9I6SjXR1A7pNkXwaTOdnMXH2In3vczQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=MAlRvXjih7ppEFi6Xf8b4jqIyh8X/t4r2ssG6C1GJzaRWOJfCFJnGIrTF9a2oozTi6y13AVK6qfBLuy4U/fxpazuWLuakwB/8qjBZVf1IXmHh518qZ3jQaeLmMS+Jv5hg3IVtogNA8NVL0AKszF4GQ1HZcrQwN2oYuy/Z4666zA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=jwBxK1Rs; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="jwBxK1Rs" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=FVpmPI05TSIP+K81Kd1Fzbdes5yFYSHh6V7vfJ86r/4=; b=jwBxK1RsoDnn1OE6ohrOqQJnCq aeU2BNeJzd8PaAMbkVibitfScV8PpDhw2C5qqk/SNj6rmGAs7N6lDReltM2egjeIQTEXw6TlSji47 ZbDGZFds0RfIne5sQ3dXPi4yp6bfUAYqTuCRjsSGz/KGIciDN8oGyx1Fh0qyQCagb0S3dq4dqhIW6 PF/Lquz8G+boUHRdnf7n9JbV67TEXc/EvFJJCJc7ShZ/88gvxvHiUSkLfWxvxQe//5qscocXBWAUb F9qEUVAlI6tpwDXW5KlLl4tc3LxcPqAWVut9H0Vq2ouiA4iSzWf4bEaL/0cEL0M49/3OgcgF4DZD5 0MaCOxPg==; Received: from hch by bombadil.infradead.org with local (Exim 4.98 #2 (Red Hat Linux)) id 1tKe4T-000000083PB-3joO; Mon, 09 Dec 2024 13:45:09 +0000 Date: Mon, 9 Dec 2024 05:45:09 -0800 From: Christoph Hellwig To: Greg KH Cc: Amir Goldstein , Christoph Hellwig , "Darrick J. Wong" , Christian Brauner , Jeff Layton , Erin Shepherd , Chuck Lever , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-nfs@vger.kernel.org, stable , Jens Axboe , Shaohua Li Subject: Re: [PATCH 0/4] exportfs: add flag to allow marking export operations as only supporting file handles Message-ID: References: <20241201-work-exportfs-v1-0-b850dda4502a@kernel.org> <20241206160358.GC7820@frogsfrogsfrogs> <2024120942-skincare-flanking-ab83@gregkh> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2024120942-skincare-flanking-ab83@gregkh> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Mon, Dec 09, 2024 at 10:16:36AM +0100, Greg KH wrote: > > Maybe we were wrong about the assumption that cgroupfs should be treated > > specially and deny export cgroups over nfs?? > > Please don't export any of the "fake" kernel filesystems (configfs, > cgroups, sysfs, debugfs, proc, etc) over nfs please. That way lies > madness and makes no sense. Umm, yes: it sounds like a pretty useless idea. But you can do that today with a userland nfs server, so why explicitly forbid it for the kernel nfs server. In either case you absolutely have to want it, you're not going to accidentally NFS export a file system. I'm still trying to understand what problem we're trying to solve here.