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 C076AC0015E for ; Tue, 1 Aug 2023 21:52:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230095AbjHAVwo (ORCPT ); Tue, 1 Aug 2023 17:52:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56044 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229535AbjHAVwn (ORCPT ); Tue, 1 Aug 2023 17:52:43 -0400 Received: from mgamail.intel.com (unknown [192.55.52.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4CAA4103; Tue, 1 Aug 2023 14:52:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1690926762; x=1722462762; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=5sHOU4Cn8TkmWYf2IYukgzv5xFMwg7J56eVFkkNFJLY=; b=bNT7mqYUMRmpD7x2+Bo0ORyT6yY0IP4jwEG5jJlBjeRfJd926RdzVC7R s+GbyNNoUnAxsYDwwjvIqp5V79obOTyVd1l6xmIvJ3L1BiggDG391ChgE ONLleFk8lvnmoeKjF+nKulo5h03lIr6JIpWr0fvMFMop9yLfRUVQ6Rh4a Qw6wEH9CfrqQe/udkHu4+t6+yFJh5/5kYR6gJGC9QHWXU+yC09uOZFa9J u8irEt8s3csqKKIuGWYDxMK/jhMCu4ZXBvv/rkqgiUMZ11c3prwA1ofkN 996xkzdoQ8AI1hU+yubuQi1kupffVRuqUc8aFgD8M235N7vYtSIrQPMQf Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10789"; a="349724999" X-IronPort-AV: E=Sophos;i="6.01,248,1684825200"; d="scan'208";a="349724999" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Aug 2023 14:52:31 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10789"; a="732141568" X-IronPort-AV: E=Sophos;i="6.01,248,1684825200"; d="scan'208";a="732141568" Received: from csegura-mobl1.amr.corp.intel.com (HELO [10.255.229.110]) ([10.255.229.110]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Aug 2023 14:52:29 -0700 Message-ID: <1b97ea8f-84fe-ac3c-7492-4d1675f7f074@intel.com> Date: Tue, 1 Aug 2023 14:52:25 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.13.0 Subject: Re: [EXTERNAL] Re: [PATCH v3] x86/hyperv: add noop functions to x86_init mpparse functions Content-Language: en-US To: Saurabh Singh Sengar , Wei Liu , Saurabh Sengar , "dave.hansen@linux.intel.com" Cc: KY Srinivasan , Haiyang Zhang , Dexuan Cui , "tglx@linutronix.de" , "mingo@redhat.com" , "bp@alien8.de" , "x86@kernel.org" , "Michael Kelley (LINUX)" , "linux-kernel@vger.kernel.org" , "linux-hyperv@vger.kernel.org" , "hpa@zytor.com" References: <1687537688-5397-1-git-send-email-ssengar@linux.microsoft.com> From: Dave Hansen In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-hyperv@vger.kernel.org On 7/21/23 05:58, Saurabh Singh Sengar wrote: >> On Fri, Jun 23, 2023 at 09:28:08AM -0700, Saurabh Sengar wrote: >>> Hyper-V can run VMs at different privilege "levels" known as Virtual >>> Trust Levels (VTL). Sometimes, it chooses to run two different VMs at >>> different levels but they share some of their address space. In such >>> setups VTL2 (higher level VM) has visibility of all of the >>> VTL0 (level 0) memory space. >>> >>> When the CONFIG_X86_MPPARSE is enabled for VTL2, the VTL2 kernel >>> performs a search within the low memory to locate MP tables. However, >>> in systems where VTL0 manages the low memory and may contain valid >>> tables, this scanning can result in incorrect MP table information >>> being provided to the VTL2 kernel, mistakenly considering VTL0's MP >>> table as its own >>> >>> Add noop functions to avoid MP parse scan by VTL2. >>> >>> Signed-off-by: Saurabh Sengar >> Hi Dave, are you happy with the commit message? > HI Dave, > > If there is no concern, can I get your ack Looks sane: Acked-by: Dave Hansen Although, if you muck with this any more having actual facts on what the "incorrect MP table information" causes would be nice too.