From patchwork Thu Mar 19 09:13:06 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11446881 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8F52013B1 for ; Thu, 19 Mar 2020 09:20:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 78E7620842 for ; Thu, 19 Mar 2020 09:20:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727351AbgCSJUD (ORCPT ); Thu, 19 Mar 2020 05:20:03 -0400 Received: from 8bytes.org ([81.169.241.247]:51922 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727211AbgCSJOX (ORCPT ); Thu, 19 Mar 2020 05:14:23 -0400 Received: by theia.8bytes.org (Postfix, from userid 1000) id 79D6C22A; Thu, 19 Mar 2020 10:14:17 +0100 (CET) From: Joerg Roedel To: x86@kernel.org Cc: hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Thomas Hellstrom , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, Joerg Roedel , Joerg Roedel Subject: [PATCH 09/70] x86/insn: Add insn_rep_prefix() helper Date: Thu, 19 Mar 2020 10:13:06 +0100 Message-Id: <20200319091407.1481-10-joro@8bytes.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200319091407.1481-1-joro@8bytes.org> References: <20200319091407.1481-1-joro@8bytes.org> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Add a function to check whether an instruction has a REP prefix. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/insn-eval.h | 1 + arch/x86/lib/insn-eval.c | 24 ++++++++++++++++++++++++ 2 files changed, 25 insertions(+) diff --git a/arch/x86/include/asm/insn-eval.h b/arch/x86/include/asm/insn-eval.h index 1e343010129e..41dee0faae97 100644 --- a/arch/x86/include/asm/insn-eval.h +++ b/arch/x86/include/asm/insn-eval.h @@ -15,6 +15,7 @@ #define INSN_CODE_SEG_OPND_SZ(params) (params & 0xf) #define INSN_CODE_SEG_PARAMS(oper_sz, addr_sz) (oper_sz | (addr_sz << 4)) +bool insn_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); diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c index f18260a19960..5d98dff5a2d7 100644 --- a/arch/x86/lib/insn-eval.c +++ b/arch/x86/lib/insn-eval.c @@ -53,6 +53,30 @@ static bool is_string_insn(struct insn *insn) } } +/** + * insn_rep_prefix() - Determine if instruction has a REP prefix + * @insn: Instruction containing the prefix to inspect + * + * Returns: + * + * true if the instruction has a REP prefix, false if not. + */ +bool insn_rep_prefix(struct insn *insn) +{ + int i; + + insn_get_prefixes(insn); + + for (i = 0; i < insn->prefixes.nbytes; i++) { + insn_byte_t p = insn->prefixes.bytes[i]; + + if (p == 0xf2 || p == 0xf3) + return true; + } + + return false; +} + /** * get_seg_reg_override_idx() - obtain segment register override index * @insn: Valid instruction with segment override prefixes