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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A82D3CE79D1 for ; Wed, 20 Sep 2023 12:05:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234577AbjITMFk (ORCPT ); Wed, 20 Sep 2023 08:05:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34014 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235177AbjITMFk (ORCPT ); Wed, 20 Sep 2023 08:05:40 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2836DA3 for ; Wed, 20 Sep 2023 05:05:34 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6F100C433C9; Wed, 20 Sep 2023 12:05:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1695211533; bh=4pNnzIrVamKs+pqyH8fCqXBWCLE8wDKuK6ULszKy8+Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lpHvQb0sgrkeg8BGF6f9ifvWG3ca6H39tn5Fp1T5lYPnlUtbrljWMG33nA9XDK4t1 V/DYf+93v+UNWwadd3oXJrnZiMI1FEt7yXPZ8ak5RF2eKy3pQl2MbvLvbHkJwS03Wg R5ShdBQx+ymratnIqUCpLFcDNKHCZyo4AmDFnH6A= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Sean Christopherson , Sasha Levin Subject: [PATCH 4.14 128/186] x86/virt: Drop unnecessary check on extended CPUID level in cpu_has_svm() Date: Wed, 20 Sep 2023 13:30:31 +0200 Message-ID: <20230920112841.649192336@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230920112836.799946261@linuxfoundation.org> References: <20230920112836.799946261@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sean Christopherson [ Upstream commit 5df8ecfe3632d5879d1f154f7aa8de441b5d1c89 ] Drop the explicit check on the extended CPUID level in cpu_has_svm(), the kernel's cached CPUID info will leave the entire SVM leaf unset if said leaf is not supported by hardware. Prior to using cached information, the check was needed to avoid false positives due to Intel's rather crazy CPUID behavior of returning the values of the maximum supported leaf if the specified leaf is unsupported. Fixes: 682a8108872f ("x86/kvm/svm: Simplify cpu_has_svm()") Link: https://lore.kernel.org/r/20230721201859.2307736-13-seanjc@google.com Signed-off-by: Sean Christopherson Signed-off-by: Sasha Levin --- arch/x86/include/asm/virtext.h | 6 ------ 1 file changed, 6 deletions(-) diff --git a/arch/x86/include/asm/virtext.h b/arch/x86/include/asm/virtext.h index 4699acd602af4..62810550024d3 100644 --- a/arch/x86/include/asm/virtext.h +++ b/arch/x86/include/asm/virtext.h @@ -89,12 +89,6 @@ static inline int cpu_has_svm(const char **msg) return 0; } - if (boot_cpu_data.extended_cpuid_level < SVM_CPUID_FUNC) { - if (msg) - *msg = "can't execute cpuid_8000000a"; - return 0; - } - if (!boot_cpu_has(X86_FEATURE_SVM)) { if (msg) *msg = "svm not available"; -- 2.40.1