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 B63853A901B; Tue, 20 Jan 2026 07:44:45 +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=1768895091; cv=none; b=SdxPMcg6fRUZMdnqviNNWPx6QSbEgaVml9Mjo+Avrx9yVA1kAxeZxkqO38Q3OZyeOVXU664ExUUmpQE4OJt2DaIS63XoMcpHAf1xLz/cRsRXThRZKZBflsdI5fM0FlzX4QSEVTzu/i4P8LIEdlC8UHl1Ndc0DA6pGvJUO/LL1sM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768895091; c=relaxed/simple; bh=ABp37W5yV5qA3LTbx53INE0UExtc+Qv1dyBs7BoHxhQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=QJW665GDAXZwzdb/cutgaTNaI+egqHNBQ/nBlVzkM+dnL78J2TLkGA4EEESCFLyOblWyMeNji1g725m/k0MnXEk8QhZKhQBjXXbCxpTQlvk43mCJCvnQkqucfYkQQzPQTfQVfBxBMrUsjSmpmIv+Syoy9cVvNmxgyb1BZ82lHbQ= 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=ilacl4zO; 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="ilacl4zO" 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=Kid6MiU7s5f8T4gEwmOyT2zu04YSeGDYh8750Mga8iQ=; b=ilacl4zOxBgb/lmdsCZTsr3EBk zFj2GyVX/vUj1UlJHTeGnpcPnHJ9j1woWxvFz3xRKDyTqK+wAajiLLU925mQ8gXwhKmyxMR4v1epI AOBbpi2btLiLaBkLAx55KwETuAMOToZG4XHJYEOLtQSWNewFbBS0oIkgoS8wa3txVmTRVKzYeS0A3 V9gH/Lab14QzzebmbPcXNWPVgrikm/JOCo+2HYwEDmDIwtOHHDne6sJtxRZS613O1tl53Srsju7g8 UT5LyUVPxepeDRdKwUet4llrhStqaMvjEAL5ucvkWWrFbYBz71lqsJk2Pg/Tigf0o/FCqWWyZna9G sV+Bbw9g==; Received: from hch by bombadil.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1vi6PX-00000003MrT-17WL; Tue, 20 Jan 2026 07:44:23 +0000 Date: Mon, 19 Jan 2026 23:44:23 -0800 From: Christoph Hellwig To: Jeff Layton Cc: Christian Brauner , Alexander Viro , Chuck Lever , NeilBrown , Olga Kornievskaia , Dai Ngo , Tom Talpey , Amir Goldstein , Hugh Dickins , Baolin Wang , Andrew Morton , Theodore Ts'o , Andreas Dilger , Jan Kara , Gao Xiang , Chao Yu , Yue Hu , Jeffle Xu , Sandeep Dhavale , Hongbo Li , Chunhai Guo , Carlos Maiolino , Ilya Dryomov , Alex Markuze , Viacheslav Dubeyko , Chris Mason , David Sterba , Luis de Bethencourt , Salah Triki , Phillip Lougher , Steve French , Paulo Alcantara , Ronnie Sahlberg , Shyam Prasad N , Bharath SM , Miklos Szeredi , Mike Marshall , Martin Brandenburg , Mark Fasheh , Joel Becker , Joseph Qi , Konstantin Komarov , Ryusuke Konishi , Trond Myklebust , Anna Schumaker , Dave Kleikamp , David Woodhouse , Richard Weinberger , Jan Kara , Andreas Gruenbacher , OGAWA Hirofumi , Jaegeuk Kim , Jonathan Corbet , David Laight , Dave Chinner , Christoph Hellwig , linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-ext4@vger.kernel.org, linux-erofs@lists.ozlabs.org, linux-xfs@vger.kernel.org, ceph-devel@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-unionfs@vger.kernel.org, devel@lists.orangefs.org, ocfs2-devel@lists.linux.dev, ntfs3@lists.linux.dev, linux-nilfs@vger.kernel.org, jfs-discussion@lists.sourceforge.net, linux-mtd@lists.infradead.org, gfs2@lists.linux.dev, linux-f2fs-devel@lists.sourceforge.net, linux-doc@vger.kernel.org Subject: Re: [PATCH v2 01/31] Documentation: document EXPORT_OP_NOLOCKS Message-ID: References: <20260119-exportfs-nfsd-v2-0-d93368f903bd@kernel.org> <20260119-exportfs-nfsd-v2-1-d93368f903bd@kernel.org> 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: <20260119-exportfs-nfsd-v2-1-d93368f903bd@kernel.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Mon, Jan 19, 2026 at 11:26:18AM -0500, Jeff Layton wrote: > + EXPORT_OP_NOLOCKS - Disable file locking on this filesystem. Some > + filesystems cannot properly support file locking as implemented by > + nfsd. A case in point is reexport of NFS itself, which can't be done > + safely without coordinating the grace period handling. Other clustered > + and networked filesystems can be problematic here as well. I'm not sure this is very useful. It really needs to document what locking semantics nfs expects, because otherwise no reader will know if they set this or not.