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 35DECCDB474 for ; Mon, 23 Oct 2023 11:30:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234067AbjJWLav (ORCPT ); Mon, 23 Oct 2023 07:30:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44900 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234070AbjJWLat (ORCPT ); Mon, 23 Oct 2023 07:30:49 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8B18AF9 for ; Mon, 23 Oct 2023 04:30:47 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BB60AC433C7; Mon, 23 Oct 2023 11:30:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1698060647; bh=tt8kn+p7dPolhVRgn3LN2gxLlBtqHsrGlNkuY/f42H4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DA6SXqG3bY1asiNU7PAOddUXKVFScDG4yVRuSktzl8CO3jHNn6aSlwkESnKUruwzt F4Vtpt5+Cw9tO1um1HnwP4Zo5l4OpytlAeYiOQIT7W2L/uzrCEUh2pMsLol3gZKdoV h5Q0qu0OG0sUxKG1pq9xfwKsJzVzh4F3T03qpb6w= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?Ren=C3=A9=20Rebe?= , "Borislav Petkov (AMD)" , stable@kernel.org Subject: [PATCH 5.4 038/123] x86/cpu: Fix AMD erratum #1485 on Zen4-based CPUs Date: Mon, 23 Oct 2023 12:56:36 +0200 Message-ID: <20231023104819.005303582@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231023104817.691299567@linuxfoundation.org> References: <20231023104817.691299567@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Borislav Petkov (AMD) commit f454b18e07f518bcd0c05af17a2239138bff52de upstream. Fix erratum #1485 on Zen4 parts where running with STIBP disabled can cause an #UD exception. The performance impact of the fix is negligible. Reported-by: René Rebe Signed-off-by: Borislav Petkov (AMD) Tested-by: René Rebe Cc: Link: https://lore.kernel.org/r/D99589F4-BC5D-430B-87B2-72C20370CF57@exactcode.com Signed-off-by: Greg Kroah-Hartman --- arch/x86/include/asm/msr-index.h | 4 ++++ arch/x86/kernel/cpu/amd.c | 8 ++++++++ 2 files changed, 12 insertions(+) --- a/arch/x86/include/asm/msr-index.h +++ b/arch/x86/include/asm/msr-index.h @@ -502,6 +502,10 @@ #define MSR_AMD64_VIRT_SPEC_CTRL 0xc001011f +/* Zen4 */ +#define MSR_ZEN4_BP_CFG 0xc001102e +#define MSR_ZEN4_BP_CFG_SHARED_BTB_FIX_BIT 5 + /* Fam 17h MSRs */ #define MSR_F17H_IRPERF 0xc00000e9 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -75,6 +75,10 @@ static const int amd_zenbleed[] = AMD_MODEL_RANGE(0x17, 0x90, 0x0, 0x91, 0xf), AMD_MODEL_RANGE(0x17, 0xa0, 0x0, 0xaf, 0xf)); +static const int amd_erratum_1485[] = + AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x19, 0x10, 0x0, 0x1f, 0xf), + AMD_MODEL_RANGE(0x19, 0x60, 0x0, 0xaf, 0xf)); + static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum) { int osvw_id = *erratum++; @@ -1117,6 +1121,10 @@ static void init_amd(struct cpuinfo_x86 check_null_seg_clears_base(c); zenbleed_check(c); + + if (!cpu_has(c, X86_FEATURE_HYPERVISOR) && + cpu_has_amd_erratum(c, amd_erratum_1485)) + msr_set_bit(MSR_ZEN4_BP_CFG, MSR_ZEN4_BP_CFG_SHARED_BTB_FIX_BIT); } #ifdef CONFIG_X86_32