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 6033ACD54AC for ; Tue, 19 Sep 2023 09:53:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231951AbjISJyA (ORCPT ); Tue, 19 Sep 2023 05:54:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36948 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231261AbjISJxV (ORCPT ); Tue, 19 Sep 2023 05:53:21 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A1C4DCCD; Tue, 19 Sep 2023 02:53:14 -0700 (PDT) Date: Tue, 19 Sep 2023 09:53:11 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1695117192; 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=mVfg5UpLxIR+jphwdBhW1SXcgM5G0tlpgt5Dqbu3w1U=; b=mQocmXbR1AjtTRvMwtNYM7eWaW8Beq6Y2ZkYg5BQLxcengiIlvKD99e8PRwl1yo7Sjy1gb 2RcP47JhKXfWQ7LkOdUzJRVj+F+7XFIUDlCE6ovOI/lQqquiiPfulvmj/mv/Lxkng/aGNT FqR/ZuwHRIJ9WFKaJVmwqgqdLUOcXgnvPmCgzAgpynZkaZAahUW/cCiHM3fZ2dNvviZmRr sbKqPKS6uGqAxewh6zFXH0T8QuJ/3w1oDLfe8YlG92PAemVR/u/qQwhGMmpj+uVggRgNXv X1HOo3u4IR4nkMZ2psnBn5LQnsJdDAFFEF/EhaTG4P/PdIxCJEkP7nIFwaPrYg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1695117192; 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=mVfg5UpLxIR+jphwdBhW1SXcgM5G0tlpgt5Dqbu3w1U=; b=nY/tFznzOd6SbLVi0KXGWD9yWZLmjX4sAsyw3Gbs4bYDLeoqNkPswhBnMTa/ZKn+C5JnxE tNtyc2cXUUZuUtCw== From: "tip-bot2 for Josh Poimboeuf" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: x86/bugs] x86/srso: Remove 'pred_cmd' label Cc: Josh Poimboeuf , Ingo Molnar , "Borislav Petkov (AMD)" , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: References: MIME-Version: 1.0 Message-ID: <169511719158.27769.3337585251495698419.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/bugs branch of tip: Commit-ID: 73163764dd8d117f2ffa14c0bc816bf1bf8a0e27 Gitweb: https://git.kernel.org/tip/73163764dd8d117f2ffa14c0bc816bf1bf8a0e27 Author: Josh Poimboeuf AuthorDate: Mon, 04 Sep 2023 22:04:57 -07:00 Committer: Ingo Molnar CommitterDate: Tue, 19 Sep 2023 11:42:47 +02:00 x86/srso: Remove 'pred_cmd' label SBPB is only enabled in two distinct cases: 1) when SRSO has been disabled with srso=off 2) when SRSO has been fixed (in future HW) Simplify the control flow by getting rid of the 'pred_cmd' label and moving the SBPB enablement check to the two corresponding code sites. This makes it more clear when exactly SBPB gets enabled. Signed-off-by: Josh Poimboeuf Signed-off-by: Ingo Molnar Acked-by: Borislav Petkov (AMD) Link: https://lore.kernel.org/r/bb20e8569cfa144def5e6f25e610804bc4974de2.1693889988.git.jpoimboe@kernel.org --- arch/x86/kernel/cpu/bugs.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index e45dd69..4f1ad23 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -2410,13 +2410,21 @@ static void __init srso_select_mitigation(void) { bool has_microcode = boot_cpu_has(X86_FEATURE_IBPB_BRTYPE); - if (!boot_cpu_has_bug(X86_BUG_SRSO) || cpu_mitigations_off()) - goto pred_cmd; + if (cpu_mitigations_off()) + return; + + if (!boot_cpu_has_bug(X86_BUG_SRSO)) { + if (boot_cpu_has(X86_FEATURE_SBPB)) + x86_pred_cmd = PRED_CMD_SBPB; + return; + } if (has_microcode) { /* * Zen1/2 with SMT off aren't vulnerable after the right * IBPB microcode has been applied. + * + * Zen1/2 don't have SBPB, no need to try to enable it here. */ if (boot_cpu_data.x86 < 0x19 && !cpu_smt_possible()) { setup_force_cpu_cap(X86_FEATURE_SRSO_NO); @@ -2439,7 +2447,9 @@ static void __init srso_select_mitigation(void) switch (srso_cmd) { case SRSO_CMD_OFF: - goto pred_cmd; + if (boot_cpu_has(X86_FEATURE_SBPB)) + x86_pred_cmd = PRED_CMD_SBPB; + return; case SRSO_CMD_MICROCODE: if (has_microcode) { @@ -2501,11 +2511,6 @@ static void __init srso_select_mitigation(void) out: pr_info("%s\n", srso_strings[srso_mitigation]); - -pred_cmd: - if ((!boot_cpu_has_bug(X86_BUG_SRSO) || srso_cmd == SRSO_CMD_OFF) && - boot_cpu_has(X86_FEATURE_SBPB)) - x86_pred_cmd = PRED_CMD_SBPB; } #undef pr_fmt