From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A2B4B4AA02A; Wed, 2 Sep 2026 16:25:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788366313; cv=none; b=gOcuwfXqNTTJGrM4b/I05Xf72qtB7HZkmTvtpGVPQ2NgZRo+pMqdZvudUm5Hk4mTaGwqHDX2VFOjJBxlCa80fciOxMOqH9L7dwFGHwlj2Jpe/uzY/lBEPlbFSo6N6m+Y4RcpKu3z7Z5ixTI5Y9PW+xQNQv1hWyOyzYP6vsiPskc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788366313; c=relaxed/simple; bh=ySYYcwlClxp/Mkrb0eAVLiKUcceiCcG4UM6cRTF2EYM=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=R+BLiQ1jfo3LdIn6X578EbBdXhusWB7a0gnaGK1Kt8+csiJYco3UpKhPoB/NNIS3NZYB/vJ6AWbZThYtC7cav1G94u5EGFpnoB0c5+0jMpLce2w86t/LzysWX7037u7mUsoQw9wzfM/BKfBJQh/VB4y/F3kKx/xkGUHnqWQbhwQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=NgQjYyLP; arc=none smtp.client-ip=198.175.65.18 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="NgQjYyLP" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1788366312; x=1819902312; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=ySYYcwlClxp/Mkrb0eAVLiKUcceiCcG4UM6cRTF2EYM=; b=NgQjYyLPYKKkWh3ic97G0Iu/SISPNdAYY/fPtZWjzcFumHZ6EjWUo1Mi brbK97Q69I7zCwNo46oNBM99ByuMI916l4uLX8olTCGwQCd+oo9O54mhW Y8e2T2Rzr9+X0AOZk9mAqMgDKR/Rjg28ueXCwU9tNaDp+0RgdXLy+Bq1N Lrzq6iwXa+LgrfpUn3sifUmQtRSut8x5GcGkdG1DsQgn4XqJHlbuZbRza gVxr6bv7rrmw8gl6XlyOYjrBb6uFM83j2H/+7hAwkz3s5dztB/uFoWJRy 9rYgFFdWPtvsSrFl+s9jz7NZxjPv4MxztsdydtO4SfqXaQM56WujjJ/Vw w==; X-CSE-ConnectionGUID: amqKp9UERgOcvtp4slqIjw== X-CSE-MsgGUID: 1E98HUrZSM2zLlz4yFZG5Q== X-IronPort-AV: E=McAfee;i="6800,10657,11894"; a="88881447" X-IronPort-AV: E=Sophos;i="6.25,258,1779174000"; d="scan'208";a="88881447" Received: from fmviesa004.fm.intel.com ([10.60.135.144]) by orvoesa110.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Sep 2026 09:25:11 -0700 X-CSE-ConnectionGUID: GbzBxvqnT8e+19c8F1v4og== X-CSE-MsgGUID: 63y2m2ghQC6izEIgTw+7GA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,258,1779174000"; d="scan'208";a="271424957" Received: from binbinwu-mobl.ccr.corp.intel.com (HELO [10.124.245.162]) ([10.124.245.162]) by fmviesa004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Sep 2026 09:25:08 -0700 Message-ID: Date: Thu, 3 Sep 2026 00:25:05 +0800 Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 1/4] KVM: TDX: Track configurable CPUID bits allowed by KVM To: "Edgecombe, Rick P" , "Li, Xiaoyao" , "kvm@vger.kernel.org" , "linux-kernel@vger.kernel.org" Cc: "kas@kernel.org" , "pbonzini@redhat.com" , "nik.borisov@suse.com" , "seanjc@google.com" , "Gao, Chao" , "dave.hansen@linux.intel.com" , "andrew.cooper3@citrix.com" References: <20260827031837.2863609-1-binbin.wu@linux.intel.com> <20260827031837.2863609-2-binbin.wu@linux.intel.com> <55488b92-66a8-45e5-ad0f-8fed63ce1187@intel.com> <6b565572-b316-4e86-906d-f150c896fe21@intel.com> <84891108-55be-48c1-9993-c730a5334d5b@linux.intel.com> <249dcccf2353181f595547d19a07232fded71023.camel@intel.com> Content-Language: en-US From: Binbin Wu In-Reply-To: <249dcccf2353181f595547d19a07232fded71023.camel@intel.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 9/3/2026 12:22 AM, Edgecombe, Rick P wrote: > On Thu, 2026-09-03 at 00:19 +0800, Binbin Wu wrote: >>> I see. You added patch 2 because without it QEMU breaks. While for >>> EST/TM2/SDBG/XTPR/DCA, QEMU doesn't break after they are turned to >>> non-configurable. QEMU cannot represent all the userspace VMM. It still has >>> the potential to breaks other userspace VMMs. >> >> I think the risk is pretty low. >> I am not sure if Sean could provide some insight about this in google's >> userspace VMM. > > Can't we fix the issue if we are wrong? I think it could be fixed to add the missing bits (if any) as bug fix.