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=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 6646BC43381 for ; Tue, 19 Feb 2019 11:35:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2BDBC2086A for ; Tue, 19 Feb 2019 11:35:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="SjwtoSl4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727582AbfBSLf3 (ORCPT ); Tue, 19 Feb 2019 06:35:29 -0500 Received: from mail-it1-f193.google.com ([209.85.166.193]:40277 "EHLO mail-it1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725772AbfBSLf3 (ORCPT ); Tue, 19 Feb 2019 06:35:29 -0500 Received: by mail-it1-f193.google.com with SMTP id i2so5320561ite.5 for ; Tue, 19 Feb 2019 03:35:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=q62Kg48ghBbijwcL6qdW6IrFyeQHl6ptcqcFoGHPA58=; b=SjwtoSl4aYbAcaO7SS5Ui6BzSU6U6HCC46Ds0w9EBHnuDtOKN7wD1HfR+V+bFLix9B T3jY1/7NUOXPDZ8sZ1/5nz/g7qk+W0FVKl238/+ZKkSH3k2y0fYqi7WZ1C2B28uzF0tJ /zDdDJcdAW42k1A0j+/sk1v/TSeg9yClehkfX7dQym24TyEIy3kdnUHJtmLZs+zRSSVJ /AzlLveNbWYL50aH7651Z4VCHQSckhXv8Jvb/9pndjjLeBfr9X1izqYAxEF70biWAZwv VBk1J6yVIfWYA8GpcHfKDXcEpJ5SQzwD9Md9fg+vE0vAeFchIOf2JkFF3jErsX7ZsBVB QlFg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=q62Kg48ghBbijwcL6qdW6IrFyeQHl6ptcqcFoGHPA58=; b=HazzbVsTYj8j1DKRxd5UIYjtyNeKHkvp2zryXmJ3RwSg8VWAObFFwnlxsspXJbQKSo 9mZPB2TE0hEipV/yR3fgj7l2IyFZfvjW5FAtJSpwtrwWTD8VUJjEeoiy5MGdkDO9XnRe P6oSCtA/Vhuuot5E4nFXogQljfam5NT/L8NIwT8rkDUe1Bw8Vum3E8y1VIQIwf+kDViP S1HvqWaTr/1/UrMmEg/VLBr1V/5bLsoipPutdM7nDSVRAR+l8b6yLtD3AlZcrq9haGur ZQ8QIzfAnuRccLqI/+7wanWcn34v6u9msS+r/HHFxuHcuI2SrwkNq1ebrNKGHt7AS1vz KmiQ== X-Gm-Message-State: AHQUAuZgyUajWGop4TusPpbjxbc299y6IUqSUL8t3ThPM7pFSJEiW5ie FgWJ3PGQ/c3c/AbbNu2X0BTji0ArbennVXggobDA5w== X-Google-Smtp-Source: AHgI3IbhGlAhVvJOxnIGcP9rZGjCooAyEe3AVeJc/1xXXTlEGXKBp5Ayp9Jq4QzlsBYVDHrelb2M8WDN4lFq/Ykqra8= X-Received: by 2002:a02:5782:: with SMTP id b2mr15174690jad.2.1550576128089; Tue, 19 Feb 2019 03:35:28 -0800 (PST) MIME-Version: 1.0 References: <20190215013959.21320-1-natechancellor@gmail.com> <20190215185026.GE15084@fuggles.cambridge.arm.com> <20190219111927.GA17012@kroah.com> In-Reply-To: <20190219111927.GA17012@kroah.com> From: Ard Biesheuvel Date: Tue, 19 Feb 2019 12:35:16 +0100 Message-ID: Subject: Re: [PATCH] arm64/neon: Disable -Wincompatible-pointer-types when building with Clang To: Greg KH Cc: Nick Desaulniers , Will Deacon , Nathan Chancellor , Catalin Marinas , Mark Brown , linux-arm-kernel , Linux Kernel Mailing List , Kevin Hilman , Sandeep Patil Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 19 Feb 2019 at 12:19, Greg KH wrote: > > On Tue, Feb 19, 2019 at 11:35:12AM +0100, Ard Biesheuvel wrote: > > On Fri, 15 Feb 2019 at 20:45, Ard Biesheuvel wrote: > > > > > > On Fri, 15 Feb 2019 at 20:43, Nick Desaulniers wrote: > > > > > > > > On Fri, Feb 15, 2019 at 11:28 AM Ard Biesheuvel > > > > wrote: > > > > > > > > > > On Fri, 15 Feb 2019 at 20:25, Nick Desaulniers wrote: > > > > > > > > > > > > On Fri, Feb 15, 2019 at 11:20 AM Ard Biesheuvel > > > > > > wrote: > > > > > > > Provided that we stop sending Clang enablement patches to -stable: > > > > > > > > > > > > What does that mean? We're trying to provide clang support back to > > > > > > 4.4 LTS branches. (so 4.4, 4.9, 4.14, 4.19). > > > > > > > > > > I understand that is what you are attempting, but that does not mean > > > > > it /belongs/ in -stable. > > > > > > > > > > There are rules for stable, and people that track stable kernels (such > > > > > as the distros) should be able to rely on us to only backport bug > > > > > fixes, not linker script changes and other updates that fix issues > > > > > that did not exist when those kernels were released. > > > > > > > > > > It is unclear to me how these clang changes benefit those users. > > > > > > > > If you're referring to > > > > https://www.spinics.net/lists/stable/msg278381.html, that's fair (I > > > > think those were helpful for LLD support on arm64). > > > > > > > > Why didn't you speak up then? Why is this coming up now? > > > > > > That is just one example, and I failed to realise it at the time. > > > > > > I think the Clang/LLVM work you are doing is very important, but I > > > simply don't think any of it belongs in -stable kernels. > > > > OK, to clarify my position: > > > > I have no problem whatsoever with taking this patch into v5.x, so > > > > Acked-by: Ard Biesheuvel > > > > but going forward, I will push back on -stable backports for > > Clang/LLVM specific changes, since they are obviously in violation of > > the stable kernel rules. > > Getting older kernels to build/run properly on newer compilers is just a > part of life for the stable trees. If you note, we have done a lot of > gcc7, then gcc8, and clang patches backported over the years in order to > make it possible for people (like me and my testing infrastructure at > the least) to keep building these old kernels on newer systems. > > So while it's not part of the "documented" rules, I do take this type of > change, as it does help out a huge population of users and testers. > That doesn't make a lot of sense to me, but that is the common practice, then I won't object any longer.