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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 930F9C64EC7 for ; Wed, 1 Mar 2023 09:02:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229553AbjCAJC2 (ORCPT ); Wed, 1 Mar 2023 04:02:28 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55496 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229769AbjCAJC1 (ORCPT ); Wed, 1 Mar 2023 04:02:27 -0500 Received: from mail-wr1-x42e.google.com (mail-wr1-x42e.google.com [IPv6:2a00:1450:4864:20::42e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 75BE82B29C for ; Wed, 1 Mar 2023 01:02:26 -0800 (PST) Received: by mail-wr1-x42e.google.com with SMTP id t15so12422018wrz.7 for ; Wed, 01 Mar 2023 01:02:26 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1677661345; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=ekZ4DgBz/58XVt2GqkwjhmN0aRNTOhzU+bBWwyMlb+U=; b=c1OWNeMO84VA6eVvCvNVbpXjP6fzotm0PAwX14XvWBKtB8g4wkaOcsPZOrvjO4JxwZ lUUoCvQM0Cc3yHwsZk0Hra3f2p7KxFtxsj6R24OQ/13UTrYg7pJP0/i+bx9FQbWDmFSB RHY2dRtPQBugNAIuHeJt46/msPZZ4t+GqGFqzIwXXLpNtfteIIcKosMy5102QCm/QBv2 O0WxUsv3NvNx5mAUBAhFAh1WfHe5y8SS3lw1rzaRyxxqD5rUvFp5eCyj18upgwjGbRkP 4wDTckzz9WSvg+T94CRo20T74jiGkZaGTN2hX0BJaItILIfpEu7pXqYU605nNX5yFuLD 2pEg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1677661345; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=ekZ4DgBz/58XVt2GqkwjhmN0aRNTOhzU+bBWwyMlb+U=; b=R/gnM3HYrMhSwd2i7WPeUfO67V7frjK/wktlrH4sJel5G5GgGVV1CLDqwmg/1h8Ssg 4BOrZ3E315bfGmRC9JQh4RJ27NDwaHGouPO2p0254gtwFJ4qZ+qaH/6VO+bgctdXx1N+ 0fqu+QkqWsV0aaq9yOR4ipUUwOfZaq9oT72IeeHmW7ou8Lavx0ijrOa1z6WL+vY8Nz46 4i6afpZA+OfS0pSC02vU+jsGAg7F26qaADnsBQalQ1G45PIw1HVdAbaDJ99oROs2ECQ2 rOCxAjzpxd7uTUAqj5zDp7Xoqwoeq4RAXy4JIaCjQxPaCsbnVFZbvH43Z+Ea4zlKw0WF DYvg== X-Gm-Message-State: AO0yUKXiQsvL3WIRvS6/LjUdzUaErsLMKgyd6uyucv6eEbBVQAGchoHp yC5KvovM6YcvH+5RIkoQ6Z1Kaw== X-Google-Smtp-Source: AK7set+NsBzCNYKPvWP7ij2i03S5Y3cTBtF/dYzRY0sFngDo55yw34iZwfYt8/GBdtP6Au6jnsondA== X-Received: by 2002:a5d:5967:0:b0:2c7:17db:bf5c with SMTP id e39-20020a5d5967000000b002c717dbbf5cmr4109821wri.25.1677661344971; Wed, 01 Mar 2023 01:02:24 -0800 (PST) Received: from [192.168.30.216] ([81.0.6.76]) by smtp.gmail.com with ESMTPSA id ja13-20020a05600c556d00b003eb596cbc54sm1168581wmb.0.2023.03.01.01.02.23 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 01 Mar 2023 01:02:24 -0800 (PST) Message-ID: Date: Wed, 1 Mar 2023 10:02:22 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0) Gecko/20100101 Thunderbird/102.8.0 Subject: Re: [PATCH v3] MIPS: Workaround clang inline compat branch issue Content-Language: en-US To: Jiaxun Yang , linux-mips@vger.kernel.org Cc: tsbogend@alpha.franken.de, nathan@kernel.org, llvm@lists.linux.dev References: <20230228193459.15365-1-jiaxun.yang@flygoat.com> From: =?UTF-8?Q?Philippe_Mathieu-Daud=c3=a9?= In-Reply-To: <20230228193459.15365-1-jiaxun.yang@flygoat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org On 28/2/23 20:34, Jiaxun Yang wrote: > Clang is unable to handle the situation that a chunk of inline > assembly ends with a compat branch instruction and then compiler > generates another control transfer instruction immediately after > this compat branch. The later instruction will end up in forbidden > slot and cause exception. > > Workaround by add a option to control the use of compact branch. > Currently it's selected by CC_IS_CLANG and hopefully we can change > it to a version check in future if clang manages to fix it. > > Fix boot on boston board. > > Link: https://github.com/llvm/llvm-project/issues/61045 > Signed-off-by: Jiaxun Yang > Acked-by: Nathan Chancellor > --- > v2: Add Link tag to LLVM bug > v3: Docuement issue link in Kconfig as well > --- > arch/mips/Kconfig | 4 ++++ > arch/mips/include/asm/asm.h | 2 +- > 2 files changed, 5 insertions(+), 1 deletion(-) Reviewed-by: Philippe Mathieu-Daudé