From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ipmail07.adl2.internode.on.net ([150.101.137.131]:12447 "EHLO ipmail07.adl2.internode.on.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725849AbeHMF0w (ORCPT ); Mon, 13 Aug 2018 01:26:52 -0400 Date: Mon, 13 Aug 2018 12:46:40 +1000 From: Dave Chinner Subject: Re: [PATCH 05/14] xfs: repair free space btrees Message-ID: <20180813024640.GB31495@dastard> References: <20180807233458.GH30972@magnolia> <20180808122953.GB2819@bfoster> <20180808224232.GJ30972@magnolia> <20180809120027.GC21030@bfoster> <20180809155959.GK30972@magnolia> <20180810103351.GA27330@bfoster> <20180810153944.GC15083@magnolia> <20180810190740.GA27589@bfoster> <20180810193651.GE15083@magnolia> <20180811125049.GA35189@bfoster> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180811125049.GA35189@bfoster> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: Brian Foster Cc: "Darrick J. Wong" , linux-xfs@vger.kernel.org, allison.henderson@oracle.com On Sat, Aug 11, 2018 at 08:50:49AM -0400, Brian Foster wrote: > On Fri, Aug 10, 2018 at 12:36:51PM -0700, Darrick J. Wong wrote: > > Technically we're not supposed to have flag days, but otoh this is a > > xfs-only ioctl for a feature that's still experimental, so perhaps it's > > not crucial to maintain compatibility with old kernels where the feature > > is incomplete and experimental? > > > > In my mind, I kind of take the experimental status as all bits/interface > may explode and are otherwise subject to change or disappear. Perhaps > others feel differently, it does seem we've kind of hinted towards the > contrary recently with respect to the per-inode dax bits and then now in > this discussion, but IMO that's kind of an inherent risk of doing > incremental work on complex features upstream. I've always considered that the experimental tag covers the user/ioctl interfaces as much as it does the functionality and on-disk format. i.e. like the on-disk format, the ioctl interfaces are subject to change until we clear the exp. tag, at which point they are essentially fixed forever. We /try/ not to have to change them after the initial merge, but sometimes we screw up and need to fix them before we commit to long term support. Cheers, Dave. -- Dave Chinner david@fromorbit.com