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 E1033C6FD1E for ; Tue, 7 Mar 2023 17:22:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231370AbjCGRWq (ORCPT ); Tue, 7 Mar 2023 12:22:46 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41700 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231368AbjCGRWW (ORCPT ); Tue, 7 Mar 2023 12:22:22 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 84B4FB746 for ; Tue, 7 Mar 2023 09:17:47 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 2422061505 for ; Tue, 7 Mar 2023 17:17:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1C257C4339C; Tue, 7 Mar 2023 17:17:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678209466; bh=N93LmdeGxLsHBMcxjud4QxgQhBafdjUUEiqNizgPKn0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eRaDkzaQC4IbPyZB36FeIv5VB4o0ImuTx+LwQHImoF9dR+LQ9lgQfuU1ar32caPQg HJX3ZUyiQgbtcLsZ+CDwLwMfiuCdS2lVGmUTjwzDtqFOhz26hQIy6uut4HPqzQqhEd OgF3J9tN49g4ETXkFknmvDxEx5JWHp/E9sAWHghk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ashok Raj , "Borislav Petkov (AMD)" , Sasha Levin Subject: [PATCH 6.2 0221/1001] x86/microcode: Add a parameter to microcode_check() to store CPU capabilities Date: Tue, 7 Mar 2023 17:49:53 +0100 Message-Id: <20230307170031.474855490@linuxfoundation.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230307170022.094103862@linuxfoundation.org> References: <20230307170022.094103862@linuxfoundation.org> User-Agent: quilt/0.67 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 From: Ashok Raj [ Upstream commit ab31c74455c64e69342ddab21fd9426fcbfefde7 ] Add a parameter to store CPU capabilities before performing a microcode update so that CPU capabilities can be compared before and after update. [ bp: Massage. ] Signed-off-by: Ashok Raj Signed-off-by: Borislav Petkov (AMD) Link: https://lore.kernel.org/r/20230109153555.4986-2-ashok.raj@intel.com Stable-dep-of: c0dd9245aa9e ("x86/microcode: Check CPU capabilities after late microcode update correctly") Signed-off-by: Sasha Levin --- arch/x86/include/asm/processor.h | 2 +- arch/x86/kernel/cpu/common.c | 21 +++++++++++++-------- arch/x86/kernel/cpu/microcode/core.c | 3 ++- 3 files changed, 16 insertions(+), 10 deletions(-) diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 4e35c66edeb7d..f256a4ddd25da 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -697,7 +697,7 @@ bool xen_set_default_idle(void); #endif void __noreturn stop_this_cpu(void *dummy); -void microcode_check(void); +void microcode_check(struct cpuinfo_x86 *prev_info); enum l1tf_mitigations { L1TF_MITIGATION_OFF, diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index f3cc7699e1e1b..cda7ded29213e 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -2302,30 +2302,35 @@ void cpu_init_secondary(void) #endif #ifdef CONFIG_MICROCODE_LATE_LOADING -/* +/** + * microcode_check() - Check if any CPU capabilities changed after an update. + * @prev_info: CPU capabilities stored before an update. + * * The microcode loader calls this upon late microcode load to recheck features, * only when microcode has been updated. Caller holds microcode_mutex and CPU * hotplug lock. + * + * Return: None */ -void microcode_check(void) +void microcode_check(struct cpuinfo_x86 *prev_info) { - struct cpuinfo_x86 info; - perf_check_microcode(); /* Reload CPUID max function as it might've changed. */ - info.cpuid_level = cpuid_eax(0); + prev_info->cpuid_level = cpuid_eax(0); /* * Copy all capability leafs to pick up the synthetic ones so that * memcmp() below doesn't fail on that. The ones coming from CPUID will * get overwritten in get_cpu_cap(). */ - memcpy(&info.x86_capability, &boot_cpu_data.x86_capability, sizeof(info.x86_capability)); + memcpy(&prev_info->x86_capability, &boot_cpu_data.x86_capability, + sizeof(prev_info->x86_capability)); - get_cpu_cap(&info); + get_cpu_cap(prev_info); - if (!memcmp(&info.x86_capability, &boot_cpu_data.x86_capability, sizeof(info.x86_capability))) + if (!memcmp(&prev_info->x86_capability, &boot_cpu_data.x86_capability, + sizeof(prev_info->x86_capability))) return; pr_warn("x86/CPU: CPU features have changed after loading microcode, but might not take effect.\n"); diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c index 712aafff96e03..b2068ce2c86bf 100644 --- a/arch/x86/kernel/cpu/microcode/core.c +++ b/arch/x86/kernel/cpu/microcode/core.c @@ -438,6 +438,7 @@ static int __reload_late(void *info) static int microcode_reload_late(void) { int old = boot_cpu_data.microcode, ret; + struct cpuinfo_x86 prev_info; pr_err("Attempting late microcode loading - it is dangerous and taints the kernel.\n"); pr_err("You should switch to early loading, if possible.\n"); @@ -447,7 +448,7 @@ static int microcode_reload_late(void) ret = stop_machine_cpuslocked(__reload_late, NULL, cpu_online_mask); if (ret == 0) - microcode_check(); + microcode_check(&prev_info); pr_info("Reload completed, microcode revision: 0x%x -> 0x%x\n", old, boot_cpu_data.microcode); -- 2.39.2