From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f199.google.com (mail-io0-f199.google.com [209.85.223.199]) by kanga.kvack.org (Postfix) with ESMTP id E35576B0006 for ; Sat, 21 Jul 2018 12:11:59 -0400 (EDT) Received: by mail-io0-f199.google.com with SMTP id o24-v6so10641532iob.20 for ; Sat, 21 Jul 2018 09:11:59 -0700 (PDT) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id e82-v6sor1313503ioe.350.2018.07.21.09.11.57 for (Google Transport Security); Sat, 21 Jul 2018 09:11:57 -0700 (PDT) MIME-Version: 1.0 References: <37267986-A987-4AD7-96CE-C1D2F116A4AC@sinenomine.net> <20180720125146.02db0f40b4edc716c6f080d2@linux-foundation.org> <20180720195746.GD7697@redhat.com> <20180720200124.GB2736@bombadil.infradead.org> <20180720201706.GE7697@redhat.com> In-Reply-To: <20180720201706.GE7697@redhat.com> From: Dan Williams Date: Sat, 21 Jul 2018 09:11:46 -0700 Message-ID: Subject: Re: [PATCH v4 0/8] mm: Rework hmm to use devm_memremap_pages and other fixes Content-Type: text/plain; charset="UTF-8" Sender: owner-linux-mm@kvack.org List-ID: To: Jerome Glisse Cc: Matthew Wilcox , Andrew Morton , mvitale@sinenomine.net, linux-mm , dan.j.williams@intel.org, jgorse@sinenomine.net, release-team@openafs.org On Fri, Jul 20, 2018 at 1:17 PM Jerome Glisse wrote: > > On Fri, Jul 20, 2018 at 01:01:24PM -0700, Matthew Wilcox wrote: > > On Fri, Jul 20, 2018 at 03:57:47PM -0400, Jerome Glisse wrote: > > > On Fri, Jul 20, 2018 at 12:51:46PM -0700, Andrew Morton wrote: > > > > Problem is, that patch is eighth in a series which we're waiting for > > > > Jerome to review and the changelog starts with "Now that all producers > > > > of dev_pagemap instances in the kernel are properly converted to > > > > EXPORT_SYMBOL_GPL...". > > > > > > I am fine with the patchset modulo GPL, i did review it in the past > > > but i did not formaly reply as i was opose to the GPL changes. So my > > > only objection is with the GPL export, everything else looks fine. > > > > Everyone from the mm side who's looked at these patches agrees that it > > reaches far too far into the guts of the mm to be anything other than > > exposing internals. It's not credible to claim that a module written that > > uses these interfaces is anything other than a derived work of the kernel. > > > > I feel these patches should be merged over Jerome's objections. > > I feel that people do not understand how far reaching this is. It means > that any new devices with memory supporting new system bus like CAPI or > CCIX will need to have a GPL driver. This is a departure of current > state of affair where we allow non GPL driver to exist. Proprietary GPU driver vendors have done just fine without us adding explicit new mechanisms for them to consume. > Moreover I have argue that HMM abstract the internal mm and by doing so > allow anyone to update the mm code without having to worried about driver > which use HMM. Thus disproving that user of HMM are tie to mm internal. No, HMM has has deployed a GPL-bypass shim into the kernel. > Also to make thing perfectly clear i am a strong proponent of open > source and i rather have a GPL driver but at the same time i do not want > linux kernel to become second citizen because it can not support new > devices ... HMM diminishes the letter and the spirit of EXPORT_SYMBOL_GPL, it grants access to and consumes GPL-only infrastructure written by me and others.