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 11104C43334 for ; Tue, 5 Jul 2022 19:48:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232958AbiGETsL (ORCPT ); Tue, 5 Jul 2022 15:48:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44784 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229849AbiGETsK (ORCPT ); Tue, 5 Jul 2022 15:48:10 -0400 Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 583671A835 for ; Tue, 5 Jul 2022 12:48:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1657050489; x=1688586489; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to; bh=YcyaUw46qwZYJmbyw8c4O2pxaPI/Doz2nUpJKZcvnQc=; b=c7OQGQ3bgh7Fg4lTrj7xVs6QfNoZtzxl06UY+Qgfvt+afbE+gQW+YBZc jz99eTbOa9/Km8f5TUJqj6OKqk0BJkhMPMUNqSNe2fw+Xz8C1WX5CKXno GGSPY/QXlp4zZWHXap9mgugRrqpQ8XeoIhKKaIkf/QDAspaa1u7voxFon N24rj0uYbxo1bvxSLDeJVzVpAXhA2GeikmQxXEHn7euhmXdqOgNinj6LP SRGqMlXVIPbxEaSCWBpGBS2u+FY+DXw27fffL0mAUKq+qh3WrNsb+Vld9 DHhbksISkFl9s4Bi8E7WZqdBa8ug+g9dGEwMtM/FLf0taTxtvtt+S3OmA Q==; X-IronPort-AV: E=McAfee;i="6400,9594,10399"; a="263258510" X-IronPort-AV: E=Sophos;i="5.92,247,1650956400"; d="scan'208";a="263258510" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Jul 2022 12:48:09 -0700 X-IronPort-AV: E=Sophos;i="5.92,247,1650956400"; d="scan'208";a="839250395" Received: from tdisanx-mobl.amr.corp.intel.com (HELO [10.209.16.32]) ([10.209.16.32]) by fmsmga006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Jul 2022 12:48:08 -0700 Content-Type: multipart/mixed; boundary="------------s14tG07WmhEwdC3tgylz9P4X" Message-ID: Date: Tue, 5 Jul 2022 12:46:10 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 Subject: Re: [PATCH] x86/split_lock: Enable the split lock detect feature on Raptor Lake P and Alder Lake N CPUs Content-Language: en-US To: Fenghua Yu , Thomas Gleixner , Borislav Petkov , Dave Hansen , Ingo Molnar , Tony Luck Cc: x86 , linux-kernel References: <20220701131958.687066-1-fenghua.yu@intel.com> From: Dave Hansen In-Reply-To: <20220701131958.687066-1-fenghua.yu@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is a multi-part message in MIME format. --------------s14tG07WmhEwdC3tgylz9P4X Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit I have an alternative patch. Let's just consider the MSR_IA32_CORE_CAPS_SPLIT_LOCK_DETECT bit to be architectural. Are there *ACTUAL* implementations where this is wrong? If not, let's just make it part of the architecture. Intel can then keep it true forever. Some documentation which says: All processors that enumerate support for MSR_IA32_CORE_CAPS and set MSR_IA32_CORE_CAPS_SPLIT_LOCK_DETECT support split lock detection. would suffice, I think. Just look at the diffstat. 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