From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f201.google.com (mail-pg1-f201.google.com [209.85.215.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6ACEB156996 for ; Tue, 9 Apr 2024 17:51:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712685076; cv=none; b=jjv0ZRxwTjuYh0VTU/oPgDPf7RyDJPuq+66g6Rf1kQIhQcwZvZO3CK1wyS/0dGln5F19TfR0Mg8hIA6/n4dM3h2ALesXqFNc0ZObzIZe5VnMk1JV0BVkS/ezrMknfEoM/IcUatcSAuD10UcPTYZ4NvrJQtYptmXySwrIqvNsW/4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712685076; c=relaxed/simple; bh=QVtEQp4/Pcfuor0ucORpy+mLoe+0G9NQLRsGApm4biU=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=B+/KbfDB+6GsOfhO3f4oKJ2+BMm30cu/ezjM4Wg0zmf5xuRw+PcyYbER+81XV+Y+69YyJM2Q/r+9kUWMENwM0J5sSXhycMOY6dtS0SlvcECuwBBkPAE499TTN67mOXXnMQrxo75KsUwK4cFyqAHK4c2BwhY/a9yPMLrpq/SkHwo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=itkF8bUI; arc=none smtp.client-ip=209.85.215.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="itkF8bUI" Received: by mail-pg1-f201.google.com with SMTP id 41be03b00d2f7-5ce67a3f275so3921614a12.0 for ; Tue, 09 Apr 2024 10:51:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1712685075; x=1713289875; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=A7D9RJgwpQ1W8M/aA/vuUOPVBx7m9VVMSR4azYK+r2U=; b=itkF8bUIabXOiKwdBCbeeKobhWElxIjYrJNzz526HLsXUB4YJyUFvtlf9irtdKrGJN sU4lz+itK40DWd6VluXd3Cqk3StVNb+rbnGQ02l2F381EX0kQcW1yjQQ5yAwnjYC5Zff YSLS/OuWJCQ/WQ5xi916NnQD8d4P75LlyqekEzVMvKf70TJ4n8zBXloWAtMAmCd9hapM Nh+Vdp+TrPSk2r+W80MGduWh+HCHuEZj0IM4U9IvdXnWW53jtsLTG1u+SPOO76eyab7C VS0Y2kZPPVs4oN4mdFKSNQDR9u0BooXAYn7L29wdLetkqur41XLZRH3Dl9P2vM7snd2h DoBQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1712685075; x=1713289875; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=A7D9RJgwpQ1W8M/aA/vuUOPVBx7m9VVMSR4azYK+r2U=; b=ZSFc6/qcpYWyrzeGYIaO64hkZXlhJKcEnNh4fH/A4mEHbWG7Dgr3dvkEnRFo0VfYos 6AyfRatCPL3ASUEtv9zKWL4pJFrlLAdGJ4Cs31L3CvMWdhnp6Dn0/MvNKGyHwhHoaZ+G hc9WzjT33pf2e4Y6uJotD3zvws9GIzTTepSDnanzJGARyox9nHbVBgQVyyKV/Fe8nqeo EUD7EJWB2dvwHGuPHCdqbVSnbZoVbpFRwROmKmqbm7r9DwRQqbMG/6btQ79g0qBIg7l0 oU4ZccZ9g0/tmwwz0scbtG5AAljkyKzjU4hFWdIAABu2/aO0DE28Qq3iXwQaauzEFFqJ G6ww== X-Gm-Message-State: AOJu0YxPuSvEfQ0MBk/oIn4avs3UQq/J+8opTI6nHI2kls+5mgM7u+gM iVu4qWcfCoH+Kuv9w0KZML5UqGcaFpLXO/9s9qEvzmLb3qXjSh20C7ci2irHgHT7gtLLGqM+hpY hTQ== X-Google-Smtp-Source: AGHT+IH/KQ46x00AZLl2fd+Lf61jBhBT8o2VrRznGwLDVKKAWw/UNewgQ/kzIVWdr4XXtJVvXT21E0kiGIY= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a05:6a02:682:b0:5cd:8454:38b2 with SMTP id ca2-20020a056a02068200b005cd845438b2mr10850pgb.11.1712685073964; Tue, 09 Apr 2024 10:51:13 -0700 (PDT) Reply-To: Sean Christopherson Date: Tue, 9 Apr 2024 10:51:06 -0700 In-Reply-To: <20240409175108.1512861-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240409175108.1512861-1-seanjc@google.com> X-Mailer: git-send-email 2.44.0.478.gd926399ef9-goog Message-ID: <20240409175108.1512861-3-seanjc@google.com> Subject: [PATCH 2/3] x86/cpu: Disable BHI mitigation by default when SPECULATION_MITIGATIONS=n From: Sean Christopherson To: Jonathan Corbet , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Peter Zijlstra , Josh Poimboeuf Cc: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Sean Christopherson , Pawan Gupta , Daniel Sneddon Content-Type: text/plain; charset="UTF-8" Rework the initialization of bhi_mitigation to use positive CONFIG tests for the ON/AUTO cases so that lack of *any* CONFIG_SPECTRE_BHI_* #define, i.e. when the kernel is built with CONFIG_SPECULATION_MITIGATIONS=n, results in the mitigation being OFF by default, not AUTO. Per the help text for SPECULATION_MITIGATIONS, the intent is that 'N' disables all mitigations. Fixes: ec9404e40e8f ("x86/bhi: Add BHI mitigation knob") Cc: stable@vger.kernel.org Cc: Pawan Gupta Cc: Daniel Sneddon Signed-off-by: Sean Christopherson --- arch/x86/kernel/cpu/bugs.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 295463707e68..e1775debeafe 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -1630,9 +1630,9 @@ enum bhi_mitigations { }; static enum bhi_mitigations bhi_mitigation __ro_after_init = - IS_ENABLED(CONFIG_SPECTRE_BHI_ON) ? BHI_MITIGATION_ON : - IS_ENABLED(CONFIG_SPECTRE_BHI_OFF) ? BHI_MITIGATION_OFF : - BHI_MITIGATION_AUTO; + IS_ENABLED(CONFIG_SPECTRE_BHI_ON) ? BHI_MITIGATION_ON : + IS_ENABLED(CONFIG_SPECTRE_BHI_AUTO) ? BHI_MITIGATION_AUTO : + BHI_MITIGATION_OFF; static int __init spectre_bhi_parse_cmdline(char *str) { -- 2.44.0.478.gd926399ef9-goog