From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.16]) (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 630FD3C98B7 for ; Fri, 9 Oct 2026 04:30:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.16 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791520203; cv=none; b=vGnOgtk2d+1YXoA80otT5YaaT4ZWGMXqp+jqWoA7eBc+5pZMPO/jmrqv/pGmt729/vUb4SQumWtDkhK72G813iH6eILCeAwz1X+YEVx6iB64WbT1qYYAociiSACuVZsY//t6wwAuBFNizwr3xRvm2GMG5i7T5DNIoUQ2LUq8EBE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791520203; c=relaxed/simple; bh=R0VieXqy7QXcl5nOFjPA3C/nOHBFSdEdyrLMUG8f/WQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=LVTwsaeTLaLJwUOebltNo5XOWsQJAPegtvqUauRUQzACSuB3/raw1AJxXmqEAiukONLkILMUDSqHKVVcYAHHTmLfCrwYNN7YhjT6AexlPCKM5XqPtcCZ+yRMUjLAWogEsq/2D+GLCudR3M2vLonDYQhB4XmA6UUqy9z6wLjBcic= 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=J+GMXtXb; arc=none smtp.client-ip=192.198.163.16 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="J+GMXtXb" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1791520200; x=1823056200; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=R0VieXqy7QXcl5nOFjPA3C/nOHBFSdEdyrLMUG8f/WQ=; b=J+GMXtXbTp1NQSJya4tNaq6O6RWJOmnE00AGHZoHvfSv271NSC/hCoup A7FF91lPx0iYqVl2p7+O+/zobffLXlXWEYtMGQdYtikgcsl39HMW0z+O3 dxAdDCviAwwAQT9zLnlQu4tgmXVvVAvB5eV9NCbn+ZGiJMMyqpc9xcaJQ PFG9gP8w82Yx7EpI+HuQLGRZmYeHGCbOggcnacKEuVgOgMiBWc/v75AMJ p61dJz9bm5ReT2IJ0g8MVjrnNvbaqJ3s+ooh/LNgM3kuiEVNAGPff+uBs TrLQj3im9t3uDUTIeBR8qUKiAFUNrm9qAgRgwxRid5XUXydezcl9DQOdQ Q==; X-CSE-ConnectionGUID: jwVmLdPjQkiIQvHEWQlvhQ== X-CSE-MsgGUID: S+bws3+NTpeg1c4xZgkoMg== X-IronPort-AV: E=McAfee;i="6800,10657,11929"; a="315601" X-IronPort-AV: E=Sophos;i="6.27,147,1787036400"; d="scan'208";a="315601" Received: from orviesa001.jf.intel.com ([10.64.159.141]) by fmvoesa110.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Oct 2026 21:29:59 -0700 X-CSE-ConnectionGUID: Tb2Tpi+FQGG8GOtVVK3pmA== X-CSE-MsgGUID: 2EiaiXtuTFSOJNYGcSRwDg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,147,1787036400"; d="scan'208";a="172104" Received: from bradocaj-mobl.ger.corp.intel.com (HELO localhost) ([10.245.246.229]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Oct 2026 21:29:52 -0700 Date: Fri, 9 Oct 2026 07:29:49 +0300 From: Tony Lindgren To: Peter Xu Cc: Kishen Maloor , Artem Bityutskiy , Paolo Bonzini , Sean Christopherson , Fabiano Rosas , Jon Grimm , Pankaj Gupta , Tom Lendacky , Marc Zyngier , Oliver Upton , Steven Price , Anup Patel , Samuel Ortiz , Jakub =?utf-8?B?UsWvxb5pxI1rYQ==?= , =?iso-8859-1?Q?J=F6rg_R=F6del?= , Vishal Annapurve , Elena Reshetova , Kai Huang , Mika Westerberg , Peter Fang , Rick Edgecombe , Xiaoyao Li , Xu Yilun , kvm@vger.kernel.org Subject: Re: [RFC PATCH v2 0/4] Add KVM API for confidential guest live migration Message-ID: References: <9fa229ea-818c-4ba9-81c6-be7ead5cb60a@intel.com> <784c4ecc-da9d-44b8-9adc-1d1e92d20ae3@intel.com> <30006d88-6679-4274-87fe-f1ce8732577c@intel.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Thu, Oct 08, 2026 at 10:31:24AM -0400, Peter Xu wrote: > On Thu, Oct 08, 2026 at 09:23:57AM +0300, Tony Lindgren wrote: > > Yes GPAs are part of the MAC generated by tdh_export_mem() so cannot change > > for import. This can be seen at the TDX module source at [0] below. > > > > What if we add a flag for the memory functions to describe the type of > > addressing used? > > > > [0] https://github.com/intel/confidential-computing.tdx.tdx-module/blob/tdx_1.5/src/vmm_dispatcher/migration_api_calls/tdh_export_mem.c#L1083 > > Could you elaborate some more? Sorry if I was a bit unclear. I meant TDX needs GPA but also other type of addressing could be added. We could specify the addressing type in struct kvm_memory_transfer flags: KVM_MEM_TRANSFER_GPA 0 KVM_MEM_TRANSFER_GMEM 1 Kishen suggested adding gmem_fd to struct kvm_memory_transfer and then for KVM_MEM_TRANSFER_GMEM the addresses would be an offsets. > IIUC if the stream is encrypted with GPA info, then the gmem offset is a > no-go, because I believe in that case we need the ability to apply a stream > of encrypted data to one guest memfd. It means even if gmemfd can be > attached to a VM before hand, it doesn't describe GPA address space, so I > don't see how to verify the encrypted GPA. Yes that's my understanding as well.