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=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 C0202C433E7 for ; Mon, 13 Jul 2020 23:40:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8B69C21473 for ; Mon, 13 Jul 2020 23:40:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594683601; bh=6rrEJJgvghk15CsdApGD/JSMn7IJrqCOSnvwvAKk4cQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=xfkQmAAUsHuU9LXv/K/Nt78nJv1UBC2V4t3VSUnUaRCBy4Op0JvxRfIMAhHHajfzq ddIyehLU8QPwxGxGmMpmstz310/200XP0bc104JWy9EfWom2fLfQzybH7FG4YsMLi+ BiCDYWhroK77AgrdQKZQctpubq8oAu7t4BXANBQQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726845AbgGMXkA (ORCPT ); Mon, 13 Jul 2020 19:40:00 -0400 Received: from mail.kernel.org ([198.145.29.99]:51650 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726339AbgGMXj7 (ORCPT ); Mon, 13 Jul 2020 19:39:59 -0400 Received: from localhost.localdomain (unknown [89.208.247.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 62D63214DB; Mon, 13 Jul 2020 23:39:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594683599; bh=6rrEJJgvghk15CsdApGD/JSMn7IJrqCOSnvwvAKk4cQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Qf6HTW4K7qcujZ2v6bi3oLAkoq0TxMt1FVb3f7mG9FioTvcQ6X8XkEjXz7Ls9xdK/ L5Pa1tLfB8JBCCaNgCR+PeJ1VZApS3oltMlVyX9wGKAVM/GJfstzNNtpbuTGoq0wLJ Klv+GnAZ1wh6fyoHrDl0oAzJn8y4EvP1MwSDFVMw= From: guoren@kernel.org To: palmerdabbelt@google.com, paul.walmsley@sifive.com, mhiramat@kernel.org, oleg@redhat.com Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, anup@brainfault.org, linux-csky@vger.kernel.org, greentime.hu@sifive.com, zong.li@sifive.com, guoren@kernel.org, me@packi.ch, bjorn.topel@gmail.com, Guo Ren Subject: [PATCH v3 3/7] riscv: Fixup kprobes handler couldn't change pc Date: Mon, 13 Jul 2020 23:39:18 +0000 Message-Id: <1594683562-68149-4-git-send-email-guoren@kernel.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1594683562-68149-1-git-send-email-guoren@kernel.org> References: <1594683562-68149-1-git-send-email-guoren@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Guo Ren The "Changing Execution Path" section in the Documentation/kprobes.txt said: Since kprobes can probe into a running kernel code, it can change the register set, including instruction pointer. Signed-off-by: Guo Ren Cc: Masami Hiramatsu Cc: Palmer Dabbelt --- arch/riscv/kernel/mcount-dyn.S | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/riscv/kernel/mcount-dyn.S b/arch/riscv/kernel/mcount-dyn.S index 35a6ed7..4b58b54 100644 --- a/arch/riscv/kernel/mcount-dyn.S +++ b/arch/riscv/kernel/mcount-dyn.S @@ -123,6 +123,7 @@ ENDPROC(ftrace_caller) sd ra, (PT_SIZE_ON_STACK+8)(sp) addi s0, sp, (PT_SIZE_ON_STACK+16) + sd ra, PT_EPC(sp) sd x1, PT_RA(sp) sd x2, PT_SP(sp) sd x3, PT_GP(sp) @@ -157,6 +158,7 @@ ENDPROC(ftrace_caller) .endm .macro RESTORE_ALL + ld ra, PT_EPC(sp) ld x1, PT_RA(sp) ld x2, PT_SP(sp) ld x3, PT_GP(sp) @@ -190,7 +192,6 @@ ENDPROC(ftrace_caller) ld x31, PT_T6(sp) ld s0, (PT_SIZE_ON_STACK)(sp) - ld ra, (PT_SIZE_ON_STACK+8)(sp) addi sp, sp, (PT_SIZE_ON_STACK+16) .endm -- 2.7.4