From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57420) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XyM5K-0008GG-OL for qemu-devel@nongnu.org; Tue, 09 Dec 2014 09:48:27 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XyM5B-0003TT-Mh for qemu-devel@nongnu.org; Tue, 09 Dec 2014 09:48:18 -0500 Received: from e34.co.us.ibm.com ([32.97.110.152]:46857) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XyM5B-0003TM-ES for qemu-devel@nongnu.org; Tue, 09 Dec 2014 09:48:09 -0500 Received: from /spool/local by e34.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 9 Dec 2014 07:48:08 -0700 Received: from b03cxnp07029.gho.boulder.ibm.com (b03cxnp07029.gho.boulder.ibm.com [9.17.130.16]) by d03dlp02.boulder.ibm.com (Postfix) with ESMTP id 059643E40040 for ; Tue, 9 Dec 2014 07:48:07 -0700 (MST) Received: from d03av01.boulder.ibm.com (d03av01.boulder.ibm.com [9.17.195.167]) by b03cxnp07029.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id sB9Em6wP45613294 for ; Tue, 9 Dec 2014 07:48:06 -0700 Received: from d03av01.boulder.ibm.com (localhost [127.0.0.1]) by d03av01.boulder.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id sB9Em6FF023932 for ; Tue, 9 Dec 2014 07:48:06 -0700 Message-ID: <54870BA5.8020905@linux.vnet.ibm.com> Date: Tue, 09 Dec 2014 09:48:05 -0500 From: Stefan Berger MIME-Version: 1.0 References: <1418134739-21627-1-git-send-email-stefanb@linux.vnet.ibm.com> <20141209143531.GA13728@redhat.com> <548709DC.4020304@linux.vnet.ibm.com> <20141209144504.GA13793@redhat.com> In-Reply-To: <20141209144504.GA13793@redhat.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 0/5] tpm: Extend the TPM TIS implementation List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: PeterHuewe@gmx.de, qemu-devel@nongnu.org On 12/09/2014 09:45 AM, Michael S. Tsirkin wrote: > On Tue, Dec 09, 2014 at 09:40:28AM -0500, Stefan Berger wrote: >> On 12/09/2014 09:35 AM, Michael S. Tsirkin wrote: >>> On Tue, Dec 09, 2014 at 09:18:54AM -0500, Stefan Berger wrote: >>>> The following series of patches extends the TPM TIS implementation to >>>> version 1.3. This will lead to a TIS version that supports TPM 2. >>>> For this I would post relatively small patches afterwards. >>>> >>>> Regards, >>>> Stefan >>> Since this is guest visible, should this be limited >>> to new machine types, to avoid breaking migrating >>> guests across hypervisor versions? >> Migration is not currently possible with TPM, since TPM (passthrough) is >> preventing it. >> >> Stefan > OK, for live migration, fair enough. > > For off-line migration: will the following still work: > - boot guest with tpm 1.3. use tpm in some way > - halt, start guest on old qemu with tpm 1.2 > ? So this is not a suspend resume operation ? Sure, it will work if the driver the OS is using works with a TPM TIS 1.3 interface and also with a TPM TIS 1.2 interface. Stefan