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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 3AC12C4743D for ; Tue, 8 Jun 2021 16:00:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1DE6C61351 for ; Tue, 8 Jun 2021 16:00:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233313AbhFHQBy (ORCPT ); Tue, 8 Jun 2021 12:01:54 -0400 Received: from mga14.intel.com ([192.55.52.115]:60385 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232870AbhFHQBv (ORCPT ); Tue, 8 Jun 2021 12:01:51 -0400 IronPort-SDR: VH+bSvsBgPUa8/VIY+oayqi1XlpMRgnWzxsvWQNcPgjxN9Ei2Q1/ovAXP7gxj9kR3mXvqFKOTS +/b2k23pY0XA== X-IronPort-AV: E=McAfee;i="6200,9189,10009"; a="204688349" X-IronPort-AV: E=Sophos;i="5.83,258,1616482800"; d="scan'208";a="204688349" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Jun 2021 08:59:57 -0700 IronPort-SDR: 2aPfQ6nUw0NrnEczUxZ1DM/AVLTjEEJ17d3GJcgwLsJfP3IIJbCPS0ghpERNOllQrE5LrLuSZr vcAq0jvs9VeQ== X-IronPort-AV: E=Sophos;i="5.83,258,1616482800"; d="scan'208";a="637683401" Received: from ticela-az-103.amr.corp.intel.com (HELO skuppusw-desk1.amr.corp.intel.com) ([10.254.36.77]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Jun 2021 08:59:56 -0700 From: Kuppuswamy Sathyanarayanan To: Peter Zijlstra , Andy Lutomirski , Dave Hansen , Tony Luck , Dan Williams Cc: Andi Kleen , Kirill Shutemov , Kuppuswamy Sathyanarayanan , Raj Ashok , Sean Christopherson , linux-kernel@vger.kernel.org, Kuppuswamy Sathyanarayanan Subject: [RFC v2-fix-v3 1/4] x86/insn-eval: Introduce insn_get_modrm_reg_ptr() Date: Tue, 8 Jun 2021 08:59:21 -0700 Message-Id: <2ee28ba6f7dd5383df4a959cc6de0dfbc859245e.1623167569.git.sathyanarayanan.kuppuswamy@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Kirill A. Shutemov" The helper returns a pointer to the register indicated by ModRM byte. It's going to replace vc_insn_get_reg() in the SEV MMIO implementation. TDX MMIO implementation will also use it. Signed-off-by: Kirill A. Shutemov Signed-off-by: Kuppuswamy Sathyanarayanan --- arch/x86/include/asm/insn-eval.h | 1 + arch/x86/lib/insn-eval.c | 20 ++++++++++++++++++++ 2 files changed, 21 insertions(+) diff --git a/arch/x86/include/asm/insn-eval.h b/arch/x86/include/asm/insn-eval.h index 91d7182ad2d6..041f399153b9 100644 --- a/arch/x86/include/asm/insn-eval.h +++ b/arch/x86/include/asm/insn-eval.h @@ -19,6 +19,7 @@ bool insn_has_rep_prefix(struct insn *insn); void __user *insn_get_addr_ref(struct insn *insn, struct pt_regs *regs); int insn_get_modrm_rm_off(struct insn *insn, struct pt_regs *regs); int insn_get_modrm_reg_off(struct insn *insn, struct pt_regs *regs); +void *insn_get_modrm_reg_ptr(struct insn *insn, struct pt_regs *regs); unsigned long insn_get_seg_base(struct pt_regs *regs, int seg_reg_idx); int insn_get_code_seg_params(struct pt_regs *regs); int insn_fetch_from_user(struct pt_regs *regs, diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c index a67afd74232c..9069d0703881 100644 --- a/arch/x86/lib/insn-eval.c +++ b/arch/x86/lib/insn-eval.c @@ -850,6 +850,26 @@ int insn_get_modrm_reg_off(struct insn *insn, struct pt_regs *regs) return get_reg_offset(insn, regs, REG_TYPE_REG); } +/** + * insn_get_modrm_reg_ptr() - Obtain register pointer based on ModRM byte + * @insn: Instruction containing the ModRM byte + * @regs: Register values as seen when entering kernel mode + * + * Returns: + * + * The register indicated by the reg part of the ModRM byte. + * The register is obtained as a pointer within pt_regs. + */ +void *insn_get_modrm_reg_ptr(struct insn *insn, struct pt_regs *regs) +{ + int offset; + + offset = insn_get_modrm_reg_off(insn, regs); + if (offset < 0) + return NULL; + return (void *)regs + offset; +} + /** * get_seg_base_limit() - obtain base address and limit of a segment * @insn: Instruction. Must be valid. -- 2.25.1