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 C8B8BC4321E for ; Wed, 30 Nov 2022 20:37:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229945AbiK3UhE (ORCPT ); Wed, 30 Nov 2022 15:37:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50400 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229649AbiK3Ugx (ORCPT ); Wed, 30 Nov 2022 15:36:53 -0500 Received: from mga06.intel.com (mga06b.intel.com [134.134.136.31]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 648CC1D3; Wed, 30 Nov 2022 12:36:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1669840612; x=1701376612; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=r1FDXbnXDjUldZm7GrdgEZtQHBGflDxjpKsRBC7x164=; b=g+PRrf0OCq3/nAYL7eotFFJNgtAt0jKI6mdn2jaWXFbYHI9Lt8pclxPT LpeAwBNChfc3Dy/tyAzN45h1Rox3v2+0gDbYp3Rt05IEC/4oeTHnDrRRB LcGYTQJa1f4vU/fEFooF/+nY8S7WzvJwqd6QApsEWXYyWeS4gjd8AH2E8 2MPjvwWyoJWD03W5GLBaDKu5PRSvmUUrLCZawtJIyDdp1YPDopV6AAgAg 6+p/SizVETWJX+X2SDeaM7xd2mZkwqz6JP4A8uR8iZGABXrEkMWPFSGcC 8fUctPZ0iIuEp3rJ4t9aK9Vqo+WiOjeuIwwg085O9CGCDO9he339rrTTC Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10547"; a="377671777" X-IronPort-AV: E=Sophos;i="5.96,207,1665471600"; d="scan'208";a="377671777" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Nov 2022 12:36:51 -0800 X-IronPort-AV: E=McAfee;i="6500,9779,10547"; a="644360640" X-IronPort-AV: E=Sophos;i="5.96,207,1665471600"; d="scan'208";a="644360640" Received: from subhadee-mobl.amr.corp.intel.com (HELO desk) ([10.251.3.232]) by orsmga002-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Nov 2022 12:36:51 -0800 Date: Wed, 30 Nov 2022 12:36:49 -0800 From: Pawan Gupta To: Kim Phillips Cc: x86@kernel.org, Babu Moger , Borislav Petkov , Borislav Petkov , Boris Ostrovsky , Dave Hansen , "H. Peter Anvin" , Ingo Molnar , Joao Martins , Jonathan Corbet , Konrad Rzeszutek Wilk , Paolo Bonzini , Sean Christopherson , Thomas Gleixner , David Woodhouse , Greg Kroah-Hartman , Juergen Gross , Peter Zijlstra , Tony Luck , Tom Lendacky , Alexey Kardashevskiy , kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 6/7] x86/cpu, kvm: Support AMD Automatic IBRS Message-ID: <20221130203649.gwhypmw35mfgwsxh@desk> References: <20221129235816.188737-1-kim.phillips@amd.com> <20221129235816.188737-7-kim.phillips@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20221129235816.188737-7-kim.phillips@amd.com> Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Tue, Nov 29, 2022 at 05:58:15PM -0600, Kim Phillips wrote: >--- a/arch/x86/kernel/cpu/common.c >+++ b/arch/x86/kernel/cpu/common.c >@@ -1406,6 +1406,14 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c) > !(ia32_cap & ARCH_CAP_PBRSB_NO)) > setup_force_cpu_bug(X86_BUG_EIBRS_PBRSB); > >+ /* >+ * AMD's AutoIBRS is equivalent to Intel's eIBRS - use the Intel flag only >+ * after IBRS_ENHANCED bugs such as BUG_EIBRS_PBRSB above have been >+ * determined. >+ */ Minor comment, setting NO_EIBRS_PBRSB in cpu_vuln_whitelist for non-EIBRS CPUs also (AMD and others) can remove this order dependency. >+ if (cpu_has(c, X86_FEATURE_AUTOIBRS)) >+ setup_force_cpu_cap(X86_FEATURE_IBRS_ENHANCED);