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 6C448C4332F for ; Wed, 4 Jan 2023 08:35:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234111AbjADIes (ORCPT ); Wed, 4 Jan 2023 03:34:48 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36478 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234034AbjADIem (ORCPT ); Wed, 4 Jan 2023 03:34:42 -0500 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5FC6F1A222 for ; Wed, 4 Jan 2023 00:34:38 -0800 (PST) Received: from kwepemi500012.china.huawei.com (unknown [172.30.72.53]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4Nn2tH1RsPz16MML; Wed, 4 Jan 2023 16:33:11 +0800 (CST) Received: from [10.67.110.108] (10.67.110.108) by kwepemi500012.china.huawei.com (7.221.188.12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.34; Wed, 4 Jan 2023 16:34:36 +0800 Message-ID: <9dacbd7a-6dc5-099c-d427-b20bfa22aabd@huawei.com> Date: Wed, 4 Jan 2023 16:34:35 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.4.2 Subject: Re: [PATCH v5 3/9] riscv/kprobe: Prepare the skeleton to prepare optimized kprobe To: =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= , Chen Guokai , , , , , , CC: , References: <20221224114315.850130-1-chenguokai17@mails.ucas.ac.cn> <20221224114315.850130-4-chenguokai17@mails.ucas.ac.cn> <87v8lovmoa.fsf@all.your.base.are.belong.to.us> From: "liaochang (A)" In-Reply-To: <87v8lovmoa.fsf@all.your.base.are.belong.to.us> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-Originating-IP: [10.67.110.108] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To kwepemi500012.china.huawei.com (7.221.188.12) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 在 2023/1/3 2:03, Björn Töpel 写道: > Chen Guokai writes: > >> From: Liao Chang > >> arch/riscv/kernel/probes/opt.c | 107 ++++++++++++++++++++++++++++++++- >> >> diff --git a/arch/riscv/kernel/probes/opt.c b/arch/riscv/kernel/probes/opt.c >> index 56c8a227c857..a4271e6033ba 100644 >> --- a/arch/riscv/kernel/probes/opt.c >> +++ b/arch/riscv/kernel/probes/opt.c > >> @@ -24,7 +72,64 @@ int arch_check_optimized_kprobe(struct optimized_kprobe *op) >> int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, >> struct kprobe *orig) >> { >> - return 0; >> + long rel; >> + int rd, ra, ret; >> + kprobe_opcode_t *code = NULL, *slot = NULL; >> + >> + if (!can_optimize((unsigned long)orig->addr, op)) >> + return -EILSEQ; >> + >> + code = kzalloc(MAX_OPTINSN_SIZE, GFP_KERNEL); >> + slot = get_optinsn_slot(); >> + if (!code || !slot) { >> + ret = -ENOMEM; >> + goto on_error; >> + } >> + >> + /* >> + * Verify if the address gap is within 4GB range, because this uses >> + * a auipc+jalr pair. > > Try to be consistent. You're mixing "AUIPC/JALR" with "auipc+jalr". OK，i will use AUIPC/JALR in all commit messages and comments of this series. > >> + */ >> + rel = (unsigned long)slot - (unsigned long)orig->addr; >> + if (!in_auipc_jalr_range(rel)) { >> + /* >> + * Different from x86, we free code buf directly instead >> of > > Reword for readers that are not familiar with x86. OK, BTW, i think the code following tag on_error is fairly self-explanatoty, perhaps this comment is no need anymore. > > > Björn -- BR, Liao, Chang