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=-13.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_IN_DEF_DKIM_WL autolearn=no 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 19998C433EF for ; Thu, 9 Sep 2021 10:53:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DEFA360FE3 for ; Thu, 9 Sep 2021 10:53:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234409AbhIIKyc (ORCPT ); Thu, 9 Sep 2021 06:54:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53048 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232903AbhIIKyY (ORCPT ); Thu, 9 Sep 2021 06:54:24 -0400 Received: from mail-oi1-x230.google.com (mail-oi1-x230.google.com [IPv6:2607:f8b0:4864:20::230]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 94BBCC061575 for ; Thu, 9 Sep 2021 03:53:15 -0700 (PDT) Received: by mail-oi1-x230.google.com with SMTP id n27so2003387oij.0 for ; Thu, 09 Sep 2021 03:53:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=fU5ufvRRjTtfwnNvK13MR5zMOLz3I8fk1OzlUMqINLQ=; b=svEsGSMujFvTtR4UMtARJNXuZvz+U/550aXRIc+7UMzXzxYASPNNCNz75C6NHgXQGg dVJIPTelpAL58scaurL0kBQOQTMznlEy8QRnyHQfYxdvgW794LiM1IeQsfZLCEJ22GDQ qeYJDSw9yib0rswsAY4EiMIpR09/rniDzcmwUBU47L1cdLS7q206vZncbq5ddz/unqpR JjT6q7GZ3YxYt0F0WB2frZxiJ2+sILr+1ax6Ri2HSHO4/nyZOnqbiOVisCjJQDDu6QAo hcv1jpLE7VOWgiP2TLIVuvoIKnrgb/YQjoBfw63Ub7F4cpzR210zw6O/4AgWl9NTv+i7 YCmw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=fU5ufvRRjTtfwnNvK13MR5zMOLz3I8fk1OzlUMqINLQ=; b=c3c2LU4qn6C3EsI3Moeav3RxnMf01jh7y4t60nK5iWeLxwt+SL/WeiEyBknjGZKYYi paShmYt038N2nDCfh/AIE8ikOf8l26e3KDfULJ95Onm99+gKW/Pv7oYjm1qtlzM5N62X tRRgqlFC/mEIPoZYRV8z84YMAnLFaSLTWCTSuqXoXUumDvx22NXqxqs9wTEPQIcDW0RP XbJJypLE38z6VkKg585ms9q2q7fZHc5eRxCrUvWnez7z08CHl80f0WC+AkcfZs/PYbyQ u8xPrXdPwr2fi85xd6VJ+Y5om1Vy3Hc+tiLOjgALzHVcrnx4cpLVZYliaRLzDHHMRhrX vvLQ== X-Gm-Message-State: AOAM531qTS3BYtyTDdPm1p5BgR70Ke22lyMYb6O/kX/57c5LaGHN41kl qxScVsEgkh/nL+yrUUkOJ+nbilFL0wjJ/0215H3l0Q== X-Google-Smtp-Source: ABdhPJypirAM1jjdo9XWTXuE1r/IYJFmD049z7WphsmfidtaQM2qvedJJrF7FPI9vKRmcHUWVT9heQSyJAVB96uljac= X-Received: by 2002:a05:6808:21a5:: with SMTP id be37mr1443831oib.172.1631184794726; Thu, 09 Sep 2021 03:53:14 -0700 (PDT) MIME-Version: 1.0 References: <20210906142615.GA1917503@roeck-us.net> <75a10e8b-9f11-64c4-460b-9f3ac09965e2@roeck-us.net> In-Reply-To: From: Marco Elver Date: Thu, 9 Sep 2021 12:53:03 +0200 Message-ID: Subject: Re: [PATCH] Enable '-Werror' by default for all kernel builds To: Christoph Hellwig Cc: Guenter Roeck , Nathan Chancellor , Arnd Bergmann , Linus Torvalds , Linux Kernel Mailing List , llvm@lists.linux.dev, Nick Desaulniers , Paul Walmsley , Palmer Dabbelt , Albert Ou , linux-riscv@lists.infradead.org, Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov , Andrey Konovalov , kasan-dev@googlegroups.com, =?UTF-8?Q?Christian_K=C3=B6nig?= , "Pan, Xinhui" , amd-gfx@lists.freedesktop.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 9 Sept 2021 at 07:59, Christoph Hellwig wrote: > On Wed, Sep 08, 2021 at 11:58:56PM +0200, Marco Elver wrote: > > It'd be good to avoid. It has helped uncover build issues with KASAN in > > the past. Or at least make it dependent on the problematic architecture= . > > For example if arm is a problem, something like this: > > I'm also seeing quite a few stack size warnings with KASAN on x86_64 > without COMPILT_TEST using gcc 10.2.1 from Debian. In fact there are a > few warnings without KASAN, but with KASAN there are a lot more. > I'll try to find some time to dig into them. Right, this reminded me that we actually at least double the real stack size for KASAN builds, because it inherently requires more stack space. I think we need Wframe-larger-than to match that, otherwise we'll just keep having this problem: https://lkml.kernel.org/r/20210909104925.809674-1-elver@google.com > While we're at it, with -Werror something like this is really futile: > > drivers/gpu/drm/amd/amdgpu/amdgpu_object.c: In function =E2=80=98amdgpu_b= o_support_uswc=E2=80=99: > drivers/gpu/drm/amd/amdgpu/amdgpu_object.c:493:2: warning: #warning > Please enable CONFIG_MTRR and CONFIG_X86_PAT for better performance thank= s to write-combining [-Wcpp > 493 | #warning Please enable CONFIG_MTRR and CONFIG_X86_PAT for better = performance \ > | ^~~~~~~