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 E822E2D5950; Tue, 13 Jan 2026 14:55:11 +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=1768316117; cv=none; b=bTAlx+QfRmnNgTuSYsj1dxuCT8V0ypHR++mZuqYAs1KoTGqWjqi4dATBwPwoS5MdoE/56IWoptgzG1h+YW2aa6ejAj3KmMZybu5D7syFgJ1IrmbkMj8qTBzaxI1c2SdyyBXr6EMbcIX7OxPeFyteIzcxoHYkg1tOFhIL1ERAuVk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768316117; c=relaxed/simple; bh=bfIM1fR8gdAxufoD568zE6Xe4mmrFMtNm5YRrKxfWsU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=cmL79ntMLhS5H1+k3qwp4/rPnbQXLVptIz0d6ubG4tB8Nzumzbdhc8DU2Y8u182WmmQp8G8AiI9iTjEoyPNvZg+dHKqS3mGK2AewcfcFDcPrnCDqqLZ/fY0d5/AczlueItfnRR19jbwPZtQ80Pk90WQ0Yr0xv5DA1weZH9gWyCk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (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=4Xu9MpV1; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (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="4Xu9MpV1" 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=P2AuSB3q0O5lkw/gF1nY/Lrh9I92MUD/Wumu9860GzA=; b=4Xu9MpV1fb36nk+xLVqjw50voP zN/I3Mf0fobYWLAtyiFh6eeo2iNKSQjTeeoaA3AO23SzK+/Vk2xX9VLh/6wcQuPfbSCvUOgDwyZYy tXshgL07k3R6MJgxwiaacOrzdFKqY26ilV+3ph2n3cLlcyEKXdyvGWC1WCSx/3BvnFpOaXNp0hUlA LOdIhx3h0ffALf9ACVX13Eu4Iz33hZNDOWMQjukRFeiggJlDl5sQ6RHc1RZf9BGxevbcm69L9/VYf CAJ9bUHsn3reBoeGpHTySi5zkROuhZhDghCw4gv3aAP/DG1boh0ciWwdyMBlKp1WmN0ZP9AS9/Kc/ 9BtfzNuw==; Received: from hch by bombadil.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1vffmt-00000007IYZ-1cGp; Tue, 13 Jan 2026 14:54:27 +0000 Date: Tue, 13 Jan 2026 06:54:27 -0800 From: Christoph Hellwig To: Christian Brauner Cc: Jeff Layton , Amir Goldstein , Chuck Lever , Jan Kara , Luis de Bethencourt , Salah Triki , Nicolas Pitre , Christoph Hellwig , Anders Larsen , Alexander Viro , David Sterba , Chris Mason , Gao Xiang , Chao Yu , Yue Hu , Jeffle Xu , Sandeep Dhavale , Hongbo Li , Chunhai Guo , Jan Kara , Theodore Ts'o , Andreas Dilger , Jaegeuk Kim , OGAWA Hirofumi , David Woodhouse , Richard Weinberger , Dave Kleikamp , Ryusuke Konishi , Viacheslav Dubeyko , Konstantin Komarov , Mark Fasheh , Joel Becker , Joseph Qi , Mike Marshall , Martin Brandenburg , Miklos Szeredi , Phillip Lougher , Carlos Maiolino , Hugh Dickins , Baolin Wang , Andrew Morton , Namjae Jeon , Sungjong Seo , Yuezhang Mo , Alexander Aring , Andreas Gruenbacher , Jonathan Corbet , "Matthew Wilcox (Oracle)" , Eric Van Hensbergen , Latchesar Ionkov , Dominique Martinet , Christian Schoenebeck , Xiubo Li , Ilya Dryomov , Trond Myklebust , Anna Schumaker , Steve French , Paulo Alcantara , Ronnie Sahlberg , Shyam Prasad N , Tom Talpey , Bharath SM , Hans de Goede , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-erofs@lists.ozlabs.org, linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-mtd@lists.infradead.org, jfs-discussion@lists.sourceforge.net, linux-nilfs@vger.kernel.org, ntfs3@lists.linux.dev, ocfs2-devel@lists.linux.dev, devel@lists.orangefs.org, linux-unionfs@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org, gfs2@lists.linux.dev, linux-doc@vger.kernel.org, v9fs@lists.linux.dev, ceph-devel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, samba-technical@lists.samba.org Subject: Re: [PATCH 00/24] vfs: require filesystems to explicitly opt-in to lease support Message-ID: References: <20260108-setlease-6-20-v1-0-ea4dec9b67fa@kernel.org> <8af369636c32b868f83669c49aea708ca3b894ac.camel@kernel.org> <20260113-mondlicht-raven-82fc4eb70e9d@brauner> Precedence: bulk X-Mailing-List: linux-btrfs@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: <20260113-mondlicht-raven-82fc4eb70e9d@brauner> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Tue, Jan 13, 2026 at 09:54:15AM +0100, Christian Brauner wrote: > I don't think we want to expose cgroupfs via NFS that's super weird. > It's like remote partial resource management and it would be very > strange if a remote process suddenly would be able to move things around > in the cgroup tree. So I would prefer to not do this. > > So my preference would be to really sever file handles from the export > mechanism so that we can allow stuff like pidfs and nsfs and cgroupfs to > use file handles via name_to_handle_at() and open_by_handle_at() without > making them exportable. I don't understand this discussion. If someone really wants to expose say cgroupfs to the network they'll find a way, be that using a userspace nfs server, samba, 9p or a custom fuse thing. What's the benefit of explicitly prohibiting a knfsd export? (not that I think any of this makes much sense to start with)