From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8A109C71155 for ; Thu, 3 Dec 2020 08:17:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2E8BC21527 for ; Thu, 3 Dec 2020 08:17:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388244AbgLCIQk (ORCPT ); Thu, 3 Dec 2020 03:16:40 -0500 Received: from verein.lst.de ([213.95.11.211]:57534 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728193AbgLCIQk (ORCPT ); Thu, 3 Dec 2020 03:16:40 -0500 Received: by verein.lst.de (Postfix, from userid 2407) id 018BA67373; Thu, 3 Dec 2020 09:15:56 +0100 (CET) Date: Thu, 3 Dec 2020 09:15:56 +0100 From: Christoph Hellwig To: ira.weiny@intel.com Cc: fstests@vger.kernel.org, Christoph Hellwig , Eric Sandeen , linux-kernel@vger.kernel.org, "Darrick J. Wong" , Dan Williams , Dave Chinner , "Theodore Y. Ts'o" , Jan Kara , Jeff Moyer , linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, David Howells Subject: Re: [PATCH] common/rc: Fix _check_s_dax() Message-ID: <20201203081556.GA15306@lst.de> References: <20201202214145.1563433-1-ira.weiny@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201202214145.1563433-1-ira.weiny@intel.com> User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Wed, Dec 02, 2020 at 01:41:45PM -0800, ira.weiny@intel.com wrote: > From: Ira Weiny > > There is a conflict with the user visible statx bits 'mount root' and > 'dax'. The kernel is changing the dax bit to correct this conflict.[1] > > Adjust _check_s_dax() to use the new bit. Because DAX tests do not run > on root mounts, STATX_ATTR_MOUNT_ROOT should always be 0, therefore we > can allow either bit to indicate DAX and cover any kernel which may be > running. > > [1] https://lore.kernel.org/lkml/3e28d2c7-fbe5-298a-13ba-dcd8fd504666@redhat.com/ > > Signed-off-by: Ira Weiny > --- > > I went ahead and used Christoph's suggestion regarding using both bits. That wasn't my suggestion. I think we should always error out when the bit value shared with STATX_ATTR_MOUNT_ROOT is seen. Because that means the kernel is not using or fixed ABI we agreed to use going forward.