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=-1.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS 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 D56C3C43381 for ; Wed, 6 Mar 2019 22:18:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A591520684 for ; Wed, 6 Mar 2019 22:18:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1551910708; bh=cHH91VKUVrdBZpo1Sg6L1dYVMh9sGYqGISnTSVGRCvU=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=W5GjYTO6Vub8J4YVTwQtJ28jN0p0bYak94XurkZkmkW0gBPULpzn0qoP7LGZH7syh UyQ5eF6Fqi1Z/KijC+7Ww+oJikp6xCtCqb0sZjBnp2FKJLCq8nk52XsAGJsRYFWL17 NuQkat3nv0d1BgT0HNpLoE79k+aOxxocnEbgDz+Y= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726395AbfCFWSX (ORCPT ); Wed, 6 Mar 2019 17:18:23 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:56420 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726196AbfCFWSX (ORCPT ); Wed, 6 Mar 2019 17:18:23 -0500 Received: from akpm3.svl.corp.google.com (unknown [104.133.8.65]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 502CB5B86; Wed, 6 Mar 2019 22:18:21 +0000 (UTC) Date: Wed, 6 Mar 2019 14:18:20 -0800 From: Andrew Morton To: Jerome Glisse Cc: Dan Williams , Linux MM , Linux Kernel Mailing List , Ralph Campbell , John Hubbard , linux-fsdevel Subject: Re: [PATCH 09/10] mm/hmm: allow to mirror vma of a file on a DAX backed filesystem Message-Id: <20190306141820.d60e47d6e173d6ec171f52cf@linux-foundation.org> In-Reply-To: <20190306154903.GA3230@redhat.com> References: <20190129212150.GP3176@redhat.com> <20190130030317.GC10462@redhat.com> <20190130183616.GB5061@redhat.com> <20190131041641.GK5061@redhat.com> <20190305141635.8134e310ba7187bc39532cd3@linux-foundation.org> <20190306154903.GA3230@redhat.com> X-Mailer: Sylpheed 3.6.0 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Wed, 6 Mar 2019 10:49:04 -0500 Jerome Glisse wrote: > On Tue, Mar 05, 2019 at 02:16:35PM -0800, Andrew Morton wrote: > > On Wed, 30 Jan 2019 21:44:46 -0800 Dan Williams wrote: > > > > > > > > > > > Another way to help allay these worries is commit to no new exports > > > > > without in-tree users. In general, that should go without saying for > > > > > any core changes for new or future hardware. > > > > > > > > I always intend to have an upstream user the issue is that the device > > > > driver tree and the mm tree move a different pace and there is always > > > > a chicken and egg problem. I do not think Andrew wants to have to > > > > merge driver patches through its tree, nor Linus want to have to merge > > > > drivers and mm trees in specific order. So it is easier to introduce > > > > mm change in one release and driver change in the next. This is what > > > > i am doing with ODP. Adding things necessary in 5.1 and working with > > > > Mellanox to have the ODP HMM patch fully tested and ready to go in > > > > 5.2 (the patch is available today and Mellanox have begin testing it > > > > AFAIK). So this is the guideline i will be following. Post mm bits > > > > with driver patches, push to merge mm bits one release and have the > > > > driver bits in the next. I do hope this sound fine to everyone. > > > > > > The track record to date has not been "merge HMM patch in one release > > > and merge the driver updates the next". If that is the plan going > > > forward that's great, and I do appreciate that this set came with > > > driver changes, and maintain hope the existing exports don't go > > > user-less for too much longer. > > > > Decision time. Jerome, how are things looking for getting these driver > > changes merged in the next cycle? > > nouveau is merge already. Confused. Nouveau in mainline is dependent upon "mm/hmm: allow to mirror vma of a file on a DAX backed filesystem"? That can't be the case? > > > > Dan, what's your overall take on this series for a 5.1-rc1 merge? > > > > Jerome, what would be the risks in skipping just this [09/10] patch? > > As nouveau is a new user it does not regress anything but for RDMA > mlx5 (which i expect to merge new window) it would regress that > driver. Also confused. How can omitting "mm/hmm: allow to mirror vma of a file on a DAX backed filesystem" from 5.1-rc1 cause an mlx5 regression?