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=-20.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 416A9C433DB for ; Wed, 3 Mar 2021 14:41:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0246E64EE1 for ; Wed, 3 Mar 2021 14:41:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235938AbhCCOkf (ORCPT ); Wed, 3 Mar 2021 09:40:35 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37802 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1843010AbhCCKXs (ORCPT ); Wed, 3 Mar 2021 05:23:48 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7AE8BC061A2D; Wed, 3 Mar 2021 00:45:36 -0800 (PST) Date: Wed, 03 Mar 2021 08:45:34 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1614761135; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=4FBeBUa3Sm/Bh/MLlPI1GauNHmGBOrSmhz43AOcCvAs=; b=o+tQ4pfTSLbKtA5R0dv9R6VZSz31lU62TttYxI1fvJi6evpdBPTR7M1QD6CT8EnbuX8FbN /rrCEtAZe1HK3/wPclVSgoULlY2lFGDQOS6aIRUK4WxN+3Z1Jmjsv3lAxLUlu6mn1zFVVS DnZ2VI7tIzt2KvFSvXW5zhXzMkhapG9RmNZIIeoKWaTgE06D2u6niH+/8ZPzG8+aLHcOYy U/fNbUS2buMrqfg/XarCiNpea3Z8Me3bw5fsmatSbLEcvuY8V+J6LI0FmEsD64kmymfIbz XxFJDOmUDSYeq467N2/zNRR1BO5vhOHfVbuWoT7m6eoIlLlSlkx8E/Ol7VkHeQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1614761135; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=4FBeBUa3Sm/Bh/MLlPI1GauNHmGBOrSmhz43AOcCvAs=; b=hJ0/JbJWxSL1K5ONvpc3QiSXRWqjRajE80d0/QchW88x9zNq/ZS8tUEYLPBGSLNBX+Set2 MOba5G9Q+2waN3Dg== From: "tip-bot2 for Peter Zijlstra" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: objtool/core] objtool,x86: Rewrite LEA decode Cc: "Peter Zijlstra (Intel)" , Josh Poimboeuf , Nick Desaulniers , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20210211173627.143250641@infradead.org> References: <20210211173627.143250641@infradead.org> MIME-Version: 1.0 Message-ID: <161476113455.20312.5856311735543250667.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the objtool/core branch of tip: Commit-ID: 7ee93978f459ace4e0fe30af582d343d5fb6421a Gitweb: https://git.kernel.org/tip/7ee93978f459ace4e0fe30af582d343d5fb6421a Author: Peter Zijlstra AuthorDate: Tue, 09 Feb 2021 21:29:16 +01:00 Committer: Peter Zijlstra CommitterDate: Wed, 03 Mar 2021 09:38:29 +01:00 objtool,x86: Rewrite LEA decode Current LEA decoding is a bunch of special cases, properly decode the instruction, with exception of full SIB and RIP-relative modes. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Tested-by: Nick Desaulniers Link: https://lkml.kernel.org/r/20210211173627.143250641@infradead.org --- tools/objtool/arch/x86/decode.c | 86 ++++++++++---------------------- 1 file changed, 28 insertions(+), 58 deletions(-) diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c index 549813c..d8f0138 100644 --- a/tools/objtool/arch/x86/decode.c +++ b/tools/objtool/arch/x86/decode.c @@ -91,9 +91,10 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec, { struct insn insn; int x86_64, sign; - unsigned char op1, op2, rex = 0, rex_b = 0, rex_r = 0, rex_w = 0, - rex_x = 0, modrm = 0, modrm_mod = 0, modrm_rm = 0, - modrm_reg = 0, sib = 0; + unsigned char op1, op2, + rex = 0, rex_b = 0, rex_r = 0, rex_w = 0, rex_x = 0, + modrm = 0, modrm_mod = 0, modrm_rm = 0, modrm_reg = 0, + sib = 0; struct stack_op *op = NULL; struct symbol *sym; @@ -328,68 +329,37 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec, break; case 0x8d: - if (sib == 0x24 && rex_w && !rex_b && !rex_x) { - - ADD_OP(op) { - if (!insn.displacement.value) { - /* lea (%rsp), reg */ - op->src.type = OP_SRC_REG; - } else { - /* lea disp(%rsp), reg */ - op->src.type = OP_SRC_ADD; - op->src.offset = insn.displacement.value; - } - op->src.reg = CFI_SP; - op->dest.type = OP_DEST_REG; - op->dest.reg = op_to_cfi_reg[modrm_reg][rex_r]; - } - - } else if (rex == 0x48 && modrm == 0x65) { - - /* lea disp(%rbp), %rsp */ - ADD_OP(op) { - op->src.type = OP_SRC_ADD; - op->src.reg = CFI_BP; - op->src.offset = insn.displacement.value; - op->dest.type = OP_DEST_REG; - op->dest.reg = CFI_SP; - } + if (modrm_mod == 3) { + WARN("invalid LEA encoding at %s:0x%lx", sec->name, offset); + break; + } - } else if (rex == 0x49 && modrm == 0x62 && - insn.displacement.value == -8) { + /* skip non 64bit ops */ + if (!rex_w) + break; - /* - * lea -0x8(%r10), %rsp - * - * Restoring rsp back to its original value after a - * stack realignment. - */ - ADD_OP(op) { - op->src.type = OP_SRC_ADD; - op->src.reg = CFI_R10; - op->src.offset = -8; - op->dest.type = OP_DEST_REG; - op->dest.reg = CFI_SP; - } + /* skip nontrivial SIB */ + if (modrm_rm == 4 && !(sib == 0x24 && rex_b == rex_x)) + break; - } else if (rex == 0x49 && modrm == 0x65 && - insn.displacement.value == -16) { + /* skip RIP relative displacement */ + if (modrm_rm == 5 && modrm_mod == 0) + break; - /* - * lea -0x10(%r13), %rsp - * - * Restoring rsp back to its original value after a - * stack realignment. - */ - ADD_OP(op) { + /* lea disp(%src), %dst */ + ADD_OP(op) { + op->src.offset = insn.displacement.value; + if (!op->src.offset) { + /* lea (%src), %dst */ + op->src.type = OP_SRC_REG; + } else { + /* lea disp(%src), %dst */ op->src.type = OP_SRC_ADD; - op->src.reg = CFI_R13; - op->src.offset = -16; - op->dest.type = OP_DEST_REG; - op->dest.reg = CFI_SP; } + op->src.reg = op_to_cfi_reg[modrm_rm][rex_b]; + op->dest.type = OP_DEST_REG; + op->dest.reg = op_to_cfi_reg[modrm_reg][rex_r]; } - break; case 0x8f: