Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757287AbbFPWVA (ORCPT ); Tue, 16 Jun 2015 18:21:00 -0400 Received: from mail-yh0-f51.google.com ([209.85.213.51]:33432 "EHLO mail-yh0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755215AbbFPWUw (ORCPT ); Tue, 16 Jun 2015 18:20:52 -0400 MIME-Version: 1.0 In-Reply-To: References: <1432163293-20965-1-git-send-email-mcgrof@do-not-panic.com> <1432163293-20965-2-git-send-email-mcgrof@do-not-panic.com> <20150521223321.GG32152@google.com> <20150522002341.GM23057@wotan.suse.de> <20150526174008.GN32152@google.com> <20150527200402.GS23057@wotan.suse.de> From: Bjorn Helgaas Date: Tue, 16 Jun 2015 17:20:31 -0500 Message-ID: Subject: Re: [PATCH v6 1/4] pci: add pci_iomap_wc() variants To: "Luis R. Rodriguez" Cc: Tomi Valkeinen , Dave Airlie , linux-fbdev , Andy Lutomirski , "linux-kernel@vger.kernel.org" , "linux-pci@vger.kernel.org" , "xen-devel@lists.xensource.com" , Toshi Kani , Suresh Siddha , Ingo Molnar , Thomas Gleixner , Juergen Gross , Daniel Vetter , Dave Airlie , Antonino Daplas , Jean-Christophe Plagniol-Villard , Dave Hansen , Arnd Bergmann , "Michael S. Tsirkin" , venkatesh.pallipadi@intel.com, Stefan Bader , =?UTF-8?B?VmlsbGUgU3lyasOkbMOk?= , Mel Gorman , Vlastimil Babka , Borislav Petkov , Davidlohr Bueso , Konrad Rzeszutek Wilk , =?UTF-8?B?VmlsbGUgU3lyasOkbMOk?= , David Vrabel , Jan Beulich , =?UTF-8?Q?Roger_Pau_Monn=C3=A9?= Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3085 Lines: 63 On Tue, Jun 16, 2015 at 2:16 PM, Luis R. Rodriguez wrote: > On Thu, May 28, 2015 at 5:36 PM, Luis R. Rodriguez > wrote: >> On Wed, May 27, 2015 at 1:04 PM, Luis R. Rodriguez wrote: >>> On Tue, May 26, 2015 at 12:40:08PM -0500, Bjorn Helgaas wrote: >>>> On Fri, May 22, 2015 at 02:23:41AM +0200, Luis R. Rodriguez wrote: >>>> > On Thu, May 21, 2015 at 05:33:21PM -0500, Bjorn Helgaas wrote: >>>> > > >>>> > > I tentatively put this (and the rest of the series) on a pci/resource >>>> > > branch. I'm hoping you'll propose some clarification about >>>> > > EXPORT_SYMBOL_GPL(). >>>> > >>>> > EXPORT_SYMBOL_GPL() also serves to ensure only GPL modules can >>>> > only run that code. So for instance although we have "Dual BSD/GPL" >>>> > tags for modules pure "BSD" tags do not exist for module tags and >>>> > cannot run EXPORT_SYMBOL_GPL() code [0]. Also there is some folks >>>> > who do believe tha at run time all kernel modules are GPL [1] [2]. >>>> > And to be precise even though the FSF may claim a list of licenses >>>> > are GPL-compatible we cannot rely on this list alone for our own >>>> > goals and if folks want to use our EXPORT_SYMBOL_GPL()s they must >>>> > discuss this on lkml [2]. >>>> >>>> By "propose some clarification," I meant that I hoped you would propose a >>>> patch to Documentation/ that would give maintainers some guidance. >>> >>> I *really really* would hate to do so but only because you insist, I'll look >>> into this... >> >> OK done. > > Bjorn, > > This is now on Jonathan Corbet's tree and visible on linux-next: > > https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/commit/?id=582ed8d51e2b6cb8a168c94852bca482685c2509 Sorry, I'm just not comfortable with using EXPORT_SYMBOL_GPL() this way. I'm happy to use it when it has a technical justification, e.g., for internal interfaces where users of the interface are clearly derived works. But pci_iomap_wc() is not in that category, and I think it should be symmetric with similar interfaces like pci_iomap() and ioremap_wc(). I don't want to use EXPORT_SYMBOL_GPL() for a random collection of things depending on the whim of the author. That makes for a messy environment to work in, and it's messy enough already. If we wanted to remove the EXPORT_SYMBOL/EXPORT_SYMBOL_GPL distinction completely, that'd be fine with me, too. But as long as we keep it, I think it should mean something more than the preference of the author. I know I did already ack this, and I even said I would merge it, but a month of thinking about this hasn't made me more comfortable with it, so I've changed my mind. I said before that I wouldn't try to stop you if you want to merge it some other way, but I don't want to ack it, and I don't want to merge it via my tree. Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/