From nobody Tue Dec 16 09:03:59 2025 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 87499C04A6A for ; Tue, 15 Aug 2023 09:58:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236328AbjHOJ6J (ORCPT ); Tue, 15 Aug 2023 05:58:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33642 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236318AbjHOJ5k (ORCPT ); Tue, 15 Aug 2023 05:57:40 -0400 Received: from mail.alien8.de (mail.alien8.de [65.109.113.108]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A530798 for ; Tue, 15 Aug 2023 02:57:38 -0700 (PDT) Received: from localhost (localhost.localdomain [127.0.0.1]) by mail.alien8.de (SuperMail on ZX Spectrum 128k) with ESMTP id 8DEE740E0196; Tue, 15 Aug 2023 09:57:36 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at mail.alien8.de Authentication-Results: mail.alien8.de (amavisd-new); dkim=pass (4096-bit key) header.d=alien8.de Received: from mail.alien8.de ([127.0.0.1]) by localhost (mail.alien8.de [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id yXjmY7c9nlce; Tue, 15 Aug 2023 09:57:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=alien8; t=1692093453; bh=sWzihh14qpIYZO0AJpRvQPWjHG8asEBhr7jBthLgdlw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Hf5wJVnPJoB9bbD6jD9VX0RpUaLbFBmpmOv2AoynQuvqRO380e58M3G7C8EgTMt/R nauriXY4cOxzoGUZOCHK26sOQKoYO8cYUwjR9RvyZdp9DF9+QSYFdfCDtCyCM27K5n olg6PdXeD5dG08yM5Ye7Td0+Dzh3USh5noBxJDd5CCCkVQBIn92opiTRkZxi6edyQ0 /QQQi2RIZxaExSdK9CFL4JZWvC/Bs7pJIii5w/SOUfE9KIxRIqH+ZNGqMaiOLE5NfO z1dWd7qs51pXVADWguVkLwUlSkyScDkqaNEvH1P45Sp3/sgYsr3VFpJNdYKt6adsBx PAbsqLDKxGOpkQCGT8yMca86xSIiiFvWZZ2L770G6YIqP+bhw0XwD4hzdVmRlSfdiX vUg9UUfUFCTcyNT848JD7A+jXKI2q1RIvbFQOSCYzz/lhOQJuVw8Xb3pgn9WElxsZC 8Z9wsbl5gq/OZFRIR6kccXEB4sCoth9WOB/aTsE5ohHBst+Cyo2Ycpno+7fB/13s9s x0j8yZoykohr6hEIOAQIBod9Bwo6E4Lc9RVK4T31fciAxXZTcCQDArfLH46ME93+YX R1lDdfT/gpk+4JuLgvwogeOjIxiuJuKluo4XjKcmE5i5e/rtzRvCs74Z5O1mZSlYd6 MjNuxo7cfnccvod6HQ349C9o= Received: from zn.tnic (pd9530d32.dip0.t-ipconnect.de [217.83.13.50]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature ECDSA (P-256) server-digest SHA256) (No client certificate requested) by mail.alien8.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 4DEED40E0194; Tue, 15 Aug 2023 09:57:28 +0000 (UTC) Date: Tue, 15 Aug 2023 11:57:24 +0200 From: Borislav Petkov To: Josh Poimboeuf Cc: Nikolay Borisov , X86 ML , Josh Poimboeuf , LKML Subject: [PATCH] x86/srso: Correct the mitigation status when SMT is disabled Message-ID: <20230815095724.GBZNtMBPUJSEegviJN@fat_crate.local> References: <20230813104517.3346-1-bp@alien8.de> <1588ed00-be11-ff9d-e4c2-12db78cca06f@suse.com> <20230814200813.p5czl47zssuej7nv@treble> <20230814202545.GKZNqNybUnKv+xyrtP@fat_crate.local> <20230814205300.krikym7jeckehqik@treble> <20230814211727.GLZNqZ5+flxtyaDjMQ@fat_crate.local> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20230814211727.GLZNqZ5+flxtyaDjMQ@fat_crate.local> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" On Mon, Aug 14, 2023 at 11:17:27PM +0200, Borislav Petkov wrote: > Lemme see how ugly it becomes tomorrow. Not too bad, considering bugs.c's ugliness. From: "Borislav Petkov (AMD)" Date: Tue, 15 Aug 2023 11:53:13 +0200 Subject: [PATCH] x86/srso: Correct the mitigation status when SMT is disabl= ed Specify how is SRSO mitigated when SMT is disabled. Also, correct the SMT check for that. Fixes: e9fbc47b818b ("x86/srso: Disable the mitigation on unaffected config= urations") Suggested-by: Josh Poimboeuf Signed-off-by: Borislav Petkov (AMD) Acked-by: Josh Poimboeuf --- arch/x86/kernel/cpu/bugs.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 6c04aef4b63b..dc8f874fdd63 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -2417,8 +2417,7 @@ static void __init srso_select_mitigation(void) * Zen1/2 with SMT off aren't vulnerable after the right * IBPB microcode has been applied. */ - if ((boot_cpu_data.x86 < 0x19) && - (!cpu_smt_possible() || (cpu_smt_control =3D=3D CPU_SMT_DISABLED))) { + if (boot_cpu_data.x86 < 0x19 && !cpu_smt_possible()) { setup_force_cpu_cap(X86_FEATURE_SRSO_NO); return; } @@ -2698,8 +2697,12 @@ static ssize_t retbleed_show_state(char *buf) =20 static ssize_t srso_show_state(char *buf) { - if (boot_cpu_has(X86_FEATURE_SRSO_NO)) - return sysfs_emit(buf, "Not affected\n"); + if (boot_cpu_has(X86_FEATURE_SRSO_NO)) { + if (sched_smt_active()) + return sysfs_emit(buf, "Not affected\n"); + else + return sysfs_emit(buf, "Mitigation: SMT disabled\n"); + } =20 return sysfs_emit(buf, "%s%s\n", srso_strings[srso_mitigation], --=20 2.42.0.rc0.25.ga82fb66fed25 --=20 Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette