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=-13.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT 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 B7977C282C7 for ; Tue, 29 Jan 2019 18:56:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7EE5420844 for ; Tue, 29 Jan 2019 18:56:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="TTogsUDS" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729255AbfA2S4F (ORCPT ); Tue, 29 Jan 2019 13:56:05 -0500 Received: from mail-pl1-f195.google.com ([209.85.214.195]:42367 "EHLO mail-pl1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726942AbfA2S4E (ORCPT ); Tue, 29 Jan 2019 13:56:04 -0500 Received: by mail-pl1-f195.google.com with SMTP id y1so9752369plp.9; Tue, 29 Jan 2019 10:56:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=6QwWpnJgv1GjxiMMzkx3rfy8vyFIphyZ17dynepjQE4=; b=TTogsUDSia1/idd3GeITuoQQBgU8LeycUtrM2B5gZ2f89QgFebjeweazVdNrvndOPN c2jbVLolQjMXZFYDOvBt5yuqsiPMHdhHdd2mtm4X7mjPZ+BIjKArgm6fWjCxu9fTDSIW pV0IoWWkSbU+hai9a8516IniV6pNkO43d0z9f9XePac07Yg3BCk+PV1LHB4ZQRZ3YCVA u0pOZyzKxGh9DSIkgY1tPmt+AfwtVS9f9YAaLgoPvG5IwQynaYi5uCSjy5806HzEl3Dj TsIFdOnEPjtQufrsEqJmTZVUBVy4mY/78ajG+T6Ozj5wR8JJ2SHEeVOTHw1bvdb+e8Dz YIQQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=6QwWpnJgv1GjxiMMzkx3rfy8vyFIphyZ17dynepjQE4=; b=XnuE9tJtIvXCa8vd+JMuvkCgkb+fcOU+95jWv+OidAutevKVm2AbD60PUR6zyAi4AE KZLr0IZd/Sv9YAykbKOii01SGtR09IhN0aWFhANGuPG992P5HR2dFc6usL0wTYLR6mNJ UDrHplVtBloakF7vsvK6RdyQdYvGTa9uSMx6TnnDGtlH+BkHBi2tAIJe8Q0ZAGzgS67l 4dkSJfWOQw2nwUFFg/c/EkAZ6EOCGXj6IHL/ap0YRQQgk8bZVI+jtMKGPFau9r/5Cfkq NHlbymEhU72KkP1W87ix3TZzA7P48b6dG9gZHmtAZLQoO2krBAo738jFKmu+5ngKvMc6 niTA== X-Gm-Message-State: AJcUukfZVYrPXzfRBKrBF7TS3dDFcnQZCeAv6adqs+z6WnbfZVsA7Yxn uTCR/79YObmXD4z5oG1yhm3/3ASF X-Google-Smtp-Source: ALg8bN69ysuxa2wXFsQb5eBbwcl6HQ4tBJSAXrcPdyjTX0x/lsR7vzHa0PHVF0l5Q5PAa7OGrQo08A== X-Received: by 2002:a17:902:292b:: with SMTP id g40mr27434840plb.82.1548788163405; Tue, 29 Jan 2019 10:56:03 -0800 (PST) Received: from localhost ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id a4sm39500514pgv.70.2019.01.29.10.56.01 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 29 Jan 2019 10:56:02 -0800 (PST) Date: Tue, 29 Jan 2019 10:56:01 -0800 From: Guenter Roeck To: Alex Deucher Cc: "Wentland, Harry" , "ndesaulniers@google.com" , "airlied@linux.ie" , "daniel@ffwll.ch" , "S@google.com" , "Laktyushkin, Dmytro" , "Zhou, David(ChunMing)" , "Li, Sun peng (Leo)" , "dri-devel@lists.freedesktop.org" , "Daenzer, Michel" , "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" , "S, Shirish" , Matthias Kaehlcke , Matthias Kaehlcke , "amd-gfx@lists.freedesktop.org" , James Y Knight , "Deucher, Alexander" , Nathan Chancellor , "Cheng, Tony" , "Koenig, Christian" Subject: Re: [PATCH] drm/amd/display: add -msse2 to prevent Clang from emitting libcalls to undefined SW FP routines Message-ID: <20190129185601.GA17525@roeck-us.net> References: <20190125005304.183322-1-ndesaulniers@google.com> <04bc6844-2a3b-2de8-60a7-a027149709fd@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jan 29, 2019 at 10:30:31AM -0500, Alex Deucher wrote: > On Fri, Jan 25, 2019 at 10:29 AM Wentland, Harry wrote: > > > > On 2019-01-24 7:52 p.m., ndesaulniers@google.com wrote: > > > arch/x86/Makefile disables SSE and SSE2 for the whole kernel. The > > > AMDGPU drivers modified in this patch re-enable SSE but not SSE2. Turn > > > on SSE2 to support emitting double precision floating point instructions > > > rather than calls to non-existent (usually available from gcc_s or > > > compiler_rt) floating point helper routines. > > > > > > Link: https://gcc.gnu.org/onlinedocs/gccint/Soft-float-library-routines.html > > > Link: https://github.com/ClangBuiltLinux/linux/issues/327 > > > Cc: stable@vger.kernel.org # 4.19 > > > Reported-by: S, Shirish > > > Reported-by: Matthias Kaehlcke > > > Suggested-by: James Y Knight > > > Suggested-by: Nathan Chancellor > > > Signed-off-by: Nick Desaulniers > > > Tested-by: Guenter Roeck > > > > Reviewed-by: Harry Wentland > > > > and applied. > > > > This patch causes a segfault: > https://bugs.freedesktop.org/show_bug.cgi?id=109487 > > Any ideas? > Set -msse2 only for clang ? I suspect, though, that this might only solve the compile problem. If I understand correctly, the first warning in the log is due to BREAK_TO_DEBUGGER(), suggesting that something is seriously wrong. Maybe enabling sse2 results in different results from floating point operations. Unfortunately I don't have a system with the affected GPU, so I can't run any tests on real hardware. Unless someone can test with real hardware, I think we have no choice but to revert the patch. Guenter > Alex > > > Harry > > > > > --- > > > drivers/gpu/drm/amd/display/dc/calcs/Makefile | 2 +- > > > drivers/gpu/drm/amd/display/dc/dml/Makefile | 2 +- > > > 2 files changed, 2 insertions(+), 2 deletions(-) > > > > > > diff --git a/drivers/gpu/drm/amd/display/dc/calcs/Makefile b/drivers/gpu/drm/amd/display/dc/calcs/Makefile > > > index 95f332ee3e7e..dc85a3c088af 100644 > > > --- a/drivers/gpu/drm/amd/display/dc/calcs/Makefile > > > +++ b/drivers/gpu/drm/amd/display/dc/calcs/Makefile > > > @@ -30,7 +30,7 @@ else ifneq ($(call cc-option, -mstack-alignment=16),) > > > cc_stack_align := -mstack-alignment=16 > > > endif > > > > > > -calcs_ccflags := -mhard-float -msse $(cc_stack_align) > > > +calcs_ccflags := -mhard-float -msse -msse2 $(cc_stack_align) > > > > > > CFLAGS_dcn_calcs.o := $(calcs_ccflags) > > > CFLAGS_dcn_calc_auto.o := $(calcs_ccflags) > > > diff --git a/drivers/gpu/drm/amd/display/dc/dml/Makefile b/drivers/gpu/drm/amd/display/dc/dml/Makefile > > > index d97ca6528f9d..33c7d7588712 100644 > > > --- a/drivers/gpu/drm/amd/display/dc/dml/Makefile > > > +++ b/drivers/gpu/drm/amd/display/dc/dml/Makefile > > > @@ -30,7 +30,7 @@ else ifneq ($(call cc-option, -mstack-alignment=16),) > > > cc_stack_align := -mstack-alignment=16 > > > endif > > > > > > -dml_ccflags := -mhard-float -msse $(cc_stack_align) > > > +dml_ccflags := -mhard-float -msse -msse2 $(cc_stack_align) > > > > > > CFLAGS_display_mode_lib.o := $(dml_ccflags) > > > CFLAGS_display_pipe_clocks.o := $(dml_ccflags) > > > > > _______________________________________________ > > amd-gfx mailing list > > amd-gfx@lists.freedesktop.org > > https://lists.freedesktop.org/mailman/listinfo/amd-gfx