From nobody Tue Dec 16 16:39:22 2025 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 1F993C77B73 for ; Sun, 23 Apr 2023 09:14:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229990AbjDWJOS (ORCPT ); Sun, 23 Apr 2023 05:14:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54040 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229470AbjDWJOQ (ORCPT ); Sun, 23 Apr 2023 05:14:16 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 673881727 for ; Sun, 23 Apr 2023 02:14:15 -0700 (PDT) Received: from kwepemi500008.china.huawei.com (unknown [172.30.72.56]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4Q42Z84gYczL0YL; Sun, 23 Apr 2023 17:11:28 +0800 (CST) Received: from huawei.com (10.67.175.83) by kwepemi500008.china.huawei.com (7.221.188.139) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.23; Sun, 23 Apr 2023 17:14:11 +0800 From: ruanjinjie To: , , , , CC: Subject: [PATCH v2] riscv: fix kprobe __user string arg print fault issue Date: Sun, 23 Apr 2023 17:12:35 +0800 Message-ID: <20230423091235.968980-1-ruanjinjie@huawei.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.67.175.83] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To kwepemi500008.china.huawei.com (7.221.188.139) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" On riscv qemu platform, when add kprobe event on do_sys_open() to show filename string arg, it just print fault as follow: echo 'p:myprobe do_sys_open dfd=3D$arg1 filename=3D+0($arg2):string flags= =3D$arg3 mode=3D$arg4' > kprobe_events bash-166 [000] ...1. 360.195367: myprobe: (do_sys_open+0x0/0x84) dfd=3D0xffffffffffffff9c filename=3D(fault) flags=3D0x8241 mode=3D0x1b6 bash-166 [000] ...1. 360.219369: myprobe: (do_sys_open+0x0/0x84) dfd=3D0xffffffffffffff9c filename=3D(fault) flags=3D0x8241 mode=3D0x1b6 bash-191 [000] ...1. 360.378827: myprobe: (do_sys_open+0x0/0x84) dfd=3D0xffffffffffffff9c filename=3D(fault) flags=3D0x98800 mode=3D0x0 As riscv do not select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE, the +0($arg2) addr is processed as a kernel address though it is a userspace address, cause the above filename=3D(fault) print. So select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE to avoid the issue, after that the kprobe trace is ok as below: bash-166 [000] ...1. 96.767641: myprobe: (do_sys_open+0x0/0x84) dfd=3D0xffffffffffffff9c filename=3D"/dev/null" flags=3D0x8241 mode=3D0x1b6 bash-166 [000] ...1. 96.793751: myprobe: (do_sys_open+0x0/0x84) dfd=3D0xffffffffffffff9c filename=3D"/dev/null" flags=3D0x8241 mode=3D0x1b6 bash-177 [000] ...1. 96.962354: myprobe: (do_sys_open+0x0/0x84) dfd=3D0xffffffffffffff9c filename=3D"/sys/kernel/debug/tracing/events/kprob= es/" flags=3D0x98800 mode=3D0x0 Signed-off-by: ruanjinjie Acked-by: Bj=C3=B6rn T=C3=B6pel --- v2: - add the config in alphabetical order --- arch/riscv/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index eb7f29a412f8..b462ed7d41fe 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -25,6 +25,7 @@ config RISCV select ARCH_HAS_GIGANTIC_PAGE select ARCH_HAS_KCOV select ARCH_HAS_MMIOWB + select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE select ARCH_HAS_PMEM_API select ARCH_HAS_PTE_SPECIAL select ARCH_HAS_SET_DIRECT_MAP if MMU --=20 2.25.1