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=-5.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 73551C433DF for ; Thu, 4 Jun 2020 03:25:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4D0AB2064C for ; Thu, 4 Jun 2020 03:25:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="b1HX7q3N" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726603AbgFDDZg (ORCPT ); Wed, 3 Jun 2020 23:25:36 -0400 Received: from mail-m973.mail.163.com ([123.126.97.3]:42902 "EHLO mail-m973.mail.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725959AbgFDDZf (ORCPT ); Wed, 3 Jun 2020 23:25:35 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=Subject:From:Message-ID:Date:MIME-Version; bh=/zqF8 1x8WepWZf34Ay0CjhkjkK5lBprvOvKC3m4ZGz0=; b=b1HX7q3NR6ft/Ho3G3sAf /DqbTw6FVMBVjbbGIM7j++5CstCxGV+HNKg8JQy5OXb/oJJgqG8+eST+/M9GSmAV QypLyWJLNMGdgEGNY+ytM9PdxT+zuS2rg1LgzZwozN9c6PjXpndyLRb2bCYO5PsK 5CG6w13rrwbn9k8JoGPtGY= Received: from [172.20.10.2] (unknown [114.242.249.96]) by smtp3 (Coremail) with SMTP id G9xpCgDH1GyWadheSIGYAA--.53S2; Thu, 04 Jun 2020 11:25:10 +0800 (CST) Subject: Re: [PATCH] function:stacktrace/mips: Fix function:stacktrace for mips To: "Maciej W. Rozycki" , WANG Xuerui Cc: tsbogend@alpha.franken.de, linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, liulichao@loongson.cn, "Maciej W. Rozycki" References: <20200528123640.4285-1-yuanjunqing66@163.com> <11c90f15-0a25-e628-c8db-53343c351085@163.com> <43f35844-f78a-74a2-0e3d-184c3567d74f@xen0n.name> From: yuanjunqing Message-ID: <810cf1b6-ce59-7570-1a5e-4fac8992a99d@163.com> Date: Thu, 4 Jun 2020 11:25:09 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=gbk Content-Transfer-Encoding: 8bit Content-Language: en-US X-CM-TRANSID: G9xpCgDH1GyWadheSIGYAA--.53S2 X-Coremail-Antispam: 1Uf129KBjvJXoW7AFW7AFWfXF15Jr1kAr4xZwb_yoW8Ww1fp3 yDAFW7Ca1jqr4j9ry2qwn5AryaqrWDGa4UGw1kJrnIk3Z0gF1SkF4Iv3WY9rZYvrW8Ca4f ur15ZrZ0vr4vkFDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07jSfOwUUUUU= X-Originating-IP: [114.242.249.96] X-CM-SenderInfo: h1xd0ypxqtx0rjwwqiywtou0bp/xtbBZAY5XFQHJrpfowABs1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ÔÚ 2020/6/4 ÉÏÎç9:17, Maciej W. Rozycki дµÀ: > On Fri, 29 May 2020, WANG Xuerui wrote: > >> On 2020/5/29 17:29, yuanjunqing wrote: >> >>>> diff --git a/arch/mips/kernel/mcount.S b/arch/mips/kernel/mcount.S >>>> index cff52b283e03..cd5545764e5f 100644 >>>> --- a/arch/mips/kernel/mcount.S >>>> +++ b/arch/mips/kernel/mcount.S >>>> @@ -87,8 +87,15 @@ EXPORT_SYMBOL(_mcount) >>>> PTR_LA t1, _etext >>>> sltu t3, t1, a0 /* t3 = (a0 > _etext) */ >>>> or t1, t2, t3 >>>> + PTR_LA t2, stlab-4 /* t2: "function:stacktrace" return address */ >>>> + move a1, AT /* arg2: parent's return address */ >>>> beqz t1, ftrace_call >>>> - nop >>>> + nop /* "function:stacktrace" return address */ >>>> +stlab: >>>> + PTR_LA t2, stlab-4 >>>> + /* ftrace_call_end: ftrace_call return address */ >>>> + beq t2,ra, ftrace_call_end >>>> + nop > Broken delay slot indentation. Thank you for your reply. For this question that you mentioned about the delay slot, I will modify my patch again. > >>>> #if defined(KBUILD_MCOUNT_RA_ADDRESS) && defined(CONFIG_32BIT) >>>> PTR_SUBU a0, a0, 16 /* arg1: adjust to module's recorded callsite */ >>>> #else >>>> @@ -98,7 +105,9 @@ EXPORT_SYMBOL(_mcount) >>>> .globl ftrace_call >>>> ftrace_call: >>>> nop /* a placeholder for the call to a real tracing function */ >>>> - move a1, AT /* arg2: parent's return address */ >>>> + move ra, t2 /* t2: "function:stacktrace" return address */ > Likewise. NB I haven't investigated if the change makes sense. A more > detailed explanation in the change description is certainly needed. I will attach a specific description for further explanation about the second patch later. > > Maciej