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=-7.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 C8EF7C48BDF for ; Thu, 10 Jun 2021 20:40:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9BC4F61412 for ; Thu, 10 Jun 2021 20:40:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231150AbhFJUmQ (ORCPT ); Thu, 10 Jun 2021 16:42:16 -0400 Received: from mail.kernel.org ([198.145.29.99]:39560 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230211AbhFJUmH (ORCPT ); Thu, 10 Jun 2021 16:42:07 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 21D3F61429; Thu, 10 Jun 2021 20:40:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1623357608; bh=cfPlMTfGXZjzDSIMKaRDT3uPARbvwJpdNQB661xjaDE=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=T0SkyKAMumx70GptKP1ts1upsmUgHa2WyIbP+37ju/tIa3qR/yyFju5IcV+1nNcDa zl0hCC7wDd6dDdkCaz3Asouv/+xfL/gHZ55l+vpJkoF9YDn5VAog1zG+AHMexfDPJy QgKfvcbDzg9YkExqbJosGyPfSz/GSPyI9CnRTITFrBEn03Q78n6mlXL6uAX1KTCI4P BnRLHtj1LcxWo4Gp4VoyjLg1KXSrjX3Cud5g5Vj+CjT04us9gCnOEvtdWg+VgHSv6/ vR8JQ/dwSNh0hMceMuhcetqxz9ii1VYQlg3N3pO4cy/RPdDdvTNzJD8/mAOansQehr qbvB94MBMLItA== Subject: Re: [PATCH] x86/Makefile: make -stack-alignment conditional on LLD < 13.0.0 To: Tor Vic , Nick Desaulniers Cc: "linux-kernel@vger.kernel.org" , "tglx@linutronix.de" , "mingo@redhat.com" , "stable@vger.kernel.org" , "clang-built-linux@googlegroups.com" , "x86@kernel.org" References: <214134496.67043.1623317284090@office.mailbox.org> <156d8beb-2644-8c2b-789b-104cf9268c8a@mailbox.org> From: Nathan Chancellor Message-ID: <3e245a20-9e5b-9122-7add-11f6eed46ca1@kernel.org> Date: Thu, 10 Jun 2021 13:40:07 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <156d8beb-2644-8c2b-789b-104cf9268c8a@mailbox.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/10/2021 1:16 PM, Tor Vic wrote: > > > On 10.06.21 19:20, Nick Desaulniers wrote: >> On Thu, Jun 10, 2021 at 2:28 AM wrote: >>> >>> Since LLVM commit 3787ee4, the '-stack-alignment' flag has been dropped [1], >>> leading to the following error message when building a LTO kernel with >>> Clang-13 and LLD-13: >>> >>> ld.lld: error: -plugin-opt=-: ld.lld: Unknown command line argument >>> '-stack-alignment=8'. Try 'ld.lld --help' >>> ld.lld: Did you mean '--stackrealign=8'? >>> >>> It also appears that the '-code-model' flag is not necessary anymore starting >>> with LLVM-9 [2]. >>> >>> Drop '-code-model' and make '-stack-alignment' conditional on LLD < 13.0.0. >> >> Please include this additional context in v2: >> ``` >> These flags were necessary because these flags were not encoded in the >> IR properly, so the link would restart optimizations without them. Now >> there are properly encoded in the IR, and these flags exposing >> implementation details are no longer necessary. >> ``` >> That way it doesn't sound like we're not using an 8B stack alignment >> on x86; we very much are so; AMDGPU GPFs without it! >> > > Will do so. > Does this have to be a v2 (with a "changes from v1" info) or just a > resend? It is based on mainline now and the line numbers have changed. Yes, this should be a v2 because the commit message changed. It would be considered a resend if nothing changed and the patch just needed to be picked up rather than re-reviewed. Cheers, Nathan