From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.12]) (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 C4FA03D967 for ; Fri, 13 Sep 2024 16:01:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.12 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726243295; cv=none; b=t7AWOns+KVRDnIbS05cjykKJCwfe7qQv9y5TnpVC1unc/01SmQqm3acyTVUkE+7GSQlPhABHf//Gt0vFPorRuFXwglVXiMAoHbW4awI4J2mnqsvG2/RIpNWBj2xEQHNXQ3UwnKbUOcNYJm54TEhEzn0/lX4+DfJ4eI3aqJsSRjQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726243295; c=relaxed/simple; bh=k63yy5dNwso41UPSHQ8/UE24Iu+86Af7ZQI4M9WW4eg=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=cKYqt4ybQ1EFdP1oa0ayoscQ7p+0NKQ3t5I3BBZt5owLhlSkBt9ls/yyRJrFZNGlEGMiV0bX7fVFl4P6PPQt629yKUhczCMOkJeFEvvbPNYDENWDBK/vl/xnRExeD5j6Xl0m6thOOEyWjpIBAqC7hVZ1m3+SAWf+ZI6vfs048Zw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=G2lx0FUl; arc=none smtp.client-ip=198.175.65.12 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="G2lx0FUl" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1726243294; x=1757779294; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=k63yy5dNwso41UPSHQ8/UE24Iu+86Af7ZQI4M9WW4eg=; b=G2lx0FUl0RiwcU62aFwm1CsemaccPtd6ukrOttOLjR8qH7S5Do7zIji2 JQS2PrkDgjvrxglpOQloQQR9fs0DhzrxJr+elQw00PV/V8JCyOToXawlr PG13TpSo7mO3VeLO+TIUvlCRMPQxN4TECjN+ZUryE6LJqL6xV+muY65M+ zqKAGpIGIN1P/StojAuxoiezOLUv7S38JaJ5QB0MsO4/eA4/f9GWRGUbc xO/HkDtu0s06pYDzqrfsPiuEDlfhs3wQtgDFB/8cZTr/5SugeK7tyJk+g HZcUqd4VtTFVrSJ+AhmZfeMqynk/5geHywPbbkDQWZyk2HqGu7JPUkR0D A==; X-CSE-ConnectionGUID: krQOdJY6TBiM26RoH+nLeQ== X-CSE-MsgGUID: 7PdT4NFiRqOqtlAjR76Nqg== X-IronPort-AV: E=McAfee;i="6700,10204,11194"; a="36496680" X-IronPort-AV: E=Sophos;i="6.10,226,1719903600"; d="scan'208";a="36496680" Received: from orviesa005.jf.intel.com ([10.64.159.145]) by orvoesa104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Sep 2024 09:01:31 -0700 X-CSE-ConnectionGUID: m1ipjbb8STC5ZiyL8P5JTQ== X-CSE-MsgGUID: T6bSxb/lTV+ZxcNAC6I9fA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.10,226,1719903600"; d="scan'208";a="72916072" Received: from ccbilbre-mobl3.amr.corp.intel.com (HELO [10.124.220.219]) ([10.124.220.219]) by orviesa005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Sep 2024 09:01:29 -0700 Message-ID: Date: Fri, 13 Sep 2024 09:01:08 -0700 Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v6 0/6] x86/tdx: Allow MMIO instructions from userspace To: "Kirill A. Shutemov" Cc: Sean Christopherson , Alexey Gladkov , linux-kernel@vger.kernel.org, linux-coco@lists.linux.dev, Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Andrew Morton , Yuan Yao , Geert Uytterhoeven , Yuntao Wang , Kai Huang , Baoquan He , Oleg Nesterov , cho@microsoft.com, decui@microsoft.com, John.Starks@microsoft.com, Paolo Bonzini References: <6c158a14-ba01-4146-9c6c-8e4c035dd055@intel.com> <039bc47c-9b5d-41f3-87da-4500731ad347@intel.com> <2v2egjmdpb2fzjriqc2ylvqns3heo5bpirtqm7cn32h3zsuwry@y5ejrbyniwxq> From: Dave Hansen Content-Language: en-US Autocrypt: addr=dave.hansen@intel.com; keydata= xsFNBE6HMP0BEADIMA3XYkQfF3dwHlj58Yjsc4E5y5G67cfbt8dvaUq2fx1lR0K9h1bOI6fC oAiUXvGAOxPDsB/P6UEOISPpLl5IuYsSwAeZGkdQ5g6m1xq7AlDJQZddhr/1DC/nMVa/2BoY 2UnKuZuSBu7lgOE193+7Uks3416N2hTkyKUSNkduyoZ9F5twiBhxPJwPtn/wnch6n5RsoXsb ygOEDxLEsSk/7eyFycjE+btUtAWZtx+HseyaGfqkZK0Z9bT1lsaHecmB203xShwCPT49Blxz VOab8668QpaEOdLGhtvrVYVK7x4skyT3nGWcgDCl5/Vp3TWA4K+IofwvXzX2ON/Mj7aQwf5W iC+3nWC7q0uxKwwsddJ0Nu+dpA/UORQWa1NiAftEoSpk5+nUUi0WE+5DRm0H+TXKBWMGNCFn c6+EKg5zQaa8KqymHcOrSXNPmzJuXvDQ8uj2J8XuzCZfK4uy1+YdIr0yyEMI7mdh4KX50LO1 pmowEqDh7dLShTOif/7UtQYrzYq9cPnjU2ZW4qd5Qz2joSGTG9eCXLz5PRe5SqHxv6ljk8mb ApNuY7bOXO/A7T2j5RwXIlcmssqIjBcxsRRoIbpCwWWGjkYjzYCjgsNFL6rt4OL11OUF37wL QcTl7fbCGv53KfKPdYD5hcbguLKi/aCccJK18ZwNjFhqr4MliQARAQABzUVEYXZpZCBDaHJp c3RvcGhlciBIYW5zZW4gKEludGVsIFdvcmsgQWRkcmVzcykgPGRhdmUuaGFuc2VuQGludGVs LmNvbT7CwXgEEwECACIFAlQ+9J0CGwMGCwkIBwMCBhUIAgkKCwQWAgMBAh4BAheAAAoJEGg1 lTBwyZKwLZUP/0dnbhDc229u2u6WtK1s1cSd9WsflGXGagkR6liJ4um3XCfYWDHvIdkHYC1t MNcVHFBwmQkawxsYvgO8kXT3SaFZe4ISfB4K4CL2qp4JO+nJdlFUbZI7cz/Td9z8nHjMcWYF IQuTsWOLs/LBMTs+ANumibtw6UkiGVD3dfHJAOPNApjVr+M0P/lVmTeP8w0uVcd2syiaU5jB aht9CYATn+ytFGWZnBEEQFnqcibIaOrmoBLu2b3fKJEd8Jp7NHDSIdrvrMjYynmc6sZKUqH2 I1qOevaa8jUg7wlLJAWGfIqnu85kkqrVOkbNbk4TPub7VOqA6qG5GCNEIv6ZY7HLYd/vAkVY E8Plzq/NwLAuOWxvGrOl7OPuwVeR4hBDfcrNb990MFPpjGgACzAZyjdmYoMu8j3/MAEW4P0z F5+EYJAOZ+z212y1pchNNauehORXgjrNKsZwxwKpPY9qb84E3O9KYpwfATsqOoQ6tTgr+1BR CCwP712H+E9U5HJ0iibN/CDZFVPL1bRerHziuwuQuvE0qWg0+0SChFe9oq0KAwEkVs6ZDMB2 P16MieEEQ6StQRlvy2YBv80L1TMl3T90Bo1UUn6ARXEpcbFE0/aORH/jEXcRteb+vuik5UGY 5TsyLYdPur3TXm7XDBdmmyQVJjnJKYK9AQxj95KlXLVO38lczsFNBFRjzmoBEACyAxbvUEhd GDGNg0JhDdezyTdN8C9BFsdxyTLnSH31NRiyp1QtuxvcqGZjb2trDVuCbIzRrgMZLVgo3upr MIOx1CXEgmn23Zhh0EpdVHM8IKx9Z7V0r+rrpRWFE8/wQZngKYVi49PGoZj50ZEifEJ5qn/H Nsp2+Y+bTUjDdgWMATg9DiFMyv8fvoqgNsNyrrZTnSgoLzdxr89FGHZCoSoAK8gfgFHuO54B lI8QOfPDG9WDPJ66HCodjTlBEr/Cwq6GruxS5i2Y33YVqxvFvDa1tUtl+iJ2SWKS9kCai2DR 3BwVONJEYSDQaven/EHMlY1q8Vln3lGPsS11vSUK3QcNJjmrgYxH5KsVsf6PNRj9mp8Z1kIG qjRx08+nnyStWC0gZH6NrYyS9rpqH3j+hA2WcI7De51L4Rv9pFwzp161mvtc6eC/GxaiUGuH BNAVP0PY0fqvIC68p3rLIAW3f97uv4ce2RSQ7LbsPsimOeCo/5vgS6YQsj83E+AipPr09Caj 0hloj+hFoqiticNpmsxdWKoOsV0PftcQvBCCYuhKbZV9s5hjt9qn8CE86A5g5KqDf83Fxqm/ vXKgHNFHE5zgXGZnrmaf6resQzbvJHO0Fb0CcIohzrpPaL3YepcLDoCCgElGMGQjdCcSQ+Ci FCRl0Bvyj1YZUql+ZkptgGjikQARAQABwsFfBBgBAgAJBQJUY85qAhsMAAoJEGg1lTBwyZKw l4IQAIKHs/9po4spZDFyfDjunimEhVHqlUt7ggR1Hsl/tkvTSze8pI1P6dGp2XW6AnH1iayn yRcoyT0ZJ+Zmm4xAH1zqKjWplzqdb/dO28qk0bPso8+1oPO8oDhLm1+tY+cOvufXkBTm+whm +AyNTjaCRt6aSMnA/QHVGSJ8grrTJCoACVNhnXg/R0g90g8iV8Q+IBZyDkG0tBThaDdw1B2l asInUTeb9EiVfL/Zjdg5VWiF9LL7iS+9hTeVdR09vThQ/DhVbCNxVk+DtyBHsjOKifrVsYep WpRGBIAu3bK8eXtyvrw1igWTNs2wazJ71+0z2jMzbclKAyRHKU9JdN6Hkkgr2nPb561yjcB8 sIq1pFXKyO+nKy6SZYxOvHxCcjk2fkw6UmPU6/j/nQlj2lfOAgNVKuDLothIxzi8pndB8Jju KktE5HJqUUMXePkAYIxEQ0mMc8Po7tuXdejgPMwgP7x65xtfEqI0RuzbUioFltsp1jUaRwQZ MTsCeQDdjpgHsj+P2ZDeEKCbma4m6Ez/YWs4+zDm1X8uZDkZcfQlD9NldbKDJEXLIjYWo1PH hYepSffIWPyvBMBTW2W5FRjJ4vLRrJSUoEfJuPQ3vW9Y73foyo/qFoURHO48AinGPZ7PC7TF vUaNOTjKedrqHkaOcqB185ahG2had0xnFsDPlx5y In-Reply-To: <2v2egjmdpb2fzjriqc2ylvqns3heo5bpirtqm7cn32h3zsuwry@y5ejrbyniwxq> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 9/13/24 08:53, Kirill A. Shutemov wrote: >> Basically: >> >> New ABI =~ Specific Kernel-mandated Instructions > If we are going to say "no" to userspace MMIO emulation for TDX, the same > has to be done for SEV. Or we can bring TDX to SEV level and draw the line > there. > > SEV and TDX run similar workloads and functional difference in this area > is hard to justify. Maybe. We definitely don't want to put any new restrictions on SEV because folks would update their kernel and old userspace would break. Or maybe we start enforcing things at >=SEV-SNP and TDX and just say that security model has changed too much to allow the old userspace.