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 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 D84E3C4321A for ; Mon, 15 Mar 2021 15:48:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B4C4A64EE1 for ; Mon, 15 Mar 2021 15:48:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234029AbhCOPsl (ORCPT ); Mon, 15 Mar 2021 11:48:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39898 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232252AbhCOPsB (ORCPT ); Mon, 15 Mar 2021 11:48:01 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 13527C0613D9; Mon, 15 Mar 2021 08:47:52 -0700 (PDT) Date: Mon, 15 Mar 2021 15:47:46 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1615823267; 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=i8CW/eaeh9X8zI5tZAZ5BXXY7XmfswsTPqJk8k9FeUo=; b=NHtqV2gtpT3e29KyOnm+yzk4RLFjbTgWPaI6/D+msJFwGO+Hrc22tAuD3f+dI7i85+HFTx SK7EuIC08Fz2H/zSuttsx1MkDYyFVtmSEVJoZNYlAluK3NzqClI1CFxkXhosTSZDZH+Bk5 glDEeISQO772LkpkkQXLDymfSOLEdj8Lr9n60aBAjs8PVprrWdgFEj01+GP2SbjT9rTXJz 229JFXT+uC/o3cP8p95cGAEVDRXrkTF4sIcwE8QttNwM1kpM+EkYWPuz3pzRxucd8R2gGt oqrrxavUoHKSYHe2fI9WKghnAh4EzwHLxmLbzv+G3vmbqvVVflp1ugdxUkx/7Q== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1615823267; 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=i8CW/eaeh9X8zI5tZAZ5BXXY7XmfswsTPqJk8k9FeUo=; b=Zw/MIlf/l6cgZLSsWhHM/H2VicyMNLPfzwkNDKg5Xl8DERdFmMlZdj+RY8q9t5XzVO71q7 l1pPeVxoJvnl0xBw== From: "tip-bot2 for Borislav Petkov" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: x86/core] x86/sev-es: Split vc_decode_insn() Cc: Borislav Petkov , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20210304174237.31945-13-bp@alien8.de> References: <20210304174237.31945-13-bp@alien8.de> MIME-Version: 1.0 Message-ID: <161582326678.398.15597396870157940621.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 x86/core branch of tip: Commit-ID: 99e4b0de4d663e247f068bb5e014593b624a4ef0 Gitweb: https://git.kernel.org/tip/99e4b0de4d663e247f068bb5e014593b624a4ef0 Author: Borislav Petkov AuthorDate: Tue, 23 Feb 2021 11:28:02 +01:00 Committer: Borislav Petkov CommitterDate: Mon, 15 Mar 2021 11:40:05 +01:00 x86/sev-es: Split vc_decode_insn() Split it into two helpers - a user- and a kernel-mode one for readability. Yes, the original function body is not that convoluted but splitting it makes following through that code trivial than having to pay attention to each little difference when in user or in kernel mode. No functional changes. Signed-off-by: Borislav Petkov Link: https://lkml.kernel.org/r/20210304174237.31945-13-bp@alien8.de --- arch/x86/kernel/sev-es.c | 59 +++++++++++++++++++++++++-------------- 1 file changed, 38 insertions(+), 21 deletions(-) diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index a28922f..043dc2f 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -251,41 +251,58 @@ static int vc_fetch_insn_kernel(struct es_em_ctxt *ctxt, return copy_from_kernel_nofault(buffer, (unsigned char *)ctxt->regs->ip, MAX_INSN_SIZE); } -static enum es_result vc_decode_insn(struct es_em_ctxt *ctxt) +static enum es_result __vc_decode_user_insn(struct es_em_ctxt *ctxt) { char buffer[MAX_INSN_SIZE]; enum es_result ret; int res; - if (user_mode(ctxt->regs)) { - res = insn_fetch_from_user_inatomic(ctxt->regs, buffer); - if (!res) { - ctxt->fi.vector = X86_TRAP_PF; - ctxt->fi.error_code = X86_PF_INSTR | X86_PF_USER; - ctxt->fi.cr2 = ctxt->regs->ip; - return ES_EXCEPTION; - } + res = insn_fetch_from_user_inatomic(ctxt->regs, buffer); + if (!res) { + ctxt->fi.vector = X86_TRAP_PF; + ctxt->fi.error_code = X86_PF_INSTR | X86_PF_USER; + ctxt->fi.cr2 = ctxt->regs->ip; + return ES_EXCEPTION; + } - if (!insn_decode_from_regs(&ctxt->insn, ctxt->regs, buffer, res)) - return ES_DECODE_FAILED; - } else { - res = vc_fetch_insn_kernel(ctxt, buffer); - if (res) { - ctxt->fi.vector = X86_TRAP_PF; - ctxt->fi.error_code = X86_PF_INSTR; - ctxt->fi.cr2 = ctxt->regs->ip; - return ES_EXCEPTION; - } + if (!insn_decode_from_regs(&ctxt->insn, ctxt->regs, buffer, res)) + return ES_DECODE_FAILED; + + ret = ctxt->insn.immediate.got ? ES_OK : ES_DECODE_FAILED; + + return ret; +} - insn_init(&ctxt->insn, buffer, MAX_INSN_SIZE, 1); - insn_get_length(&ctxt->insn); +static enum es_result __vc_decode_kern_insn(struct es_em_ctxt *ctxt) +{ + char buffer[MAX_INSN_SIZE]; + enum es_result ret; + int res; + + res = vc_fetch_insn_kernel(ctxt, buffer); + if (res) { + ctxt->fi.vector = X86_TRAP_PF; + ctxt->fi.error_code = X86_PF_INSTR; + ctxt->fi.cr2 = ctxt->regs->ip; + return ES_EXCEPTION; } + insn_init(&ctxt->insn, buffer, MAX_INSN_SIZE, 1); + insn_get_length(&ctxt->insn); + ret = ctxt->insn.immediate.got ? ES_OK : ES_DECODE_FAILED; return ret; } +static enum es_result vc_decode_insn(struct es_em_ctxt *ctxt) +{ + if (user_mode(ctxt->regs)) + return __vc_decode_user_insn(ctxt); + else + return __vc_decode_kern_insn(ctxt); +} + static enum es_result vc_write_mem(struct es_em_ctxt *ctxt, char *dst, char *buf, size_t size) {