From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefan Berger Subject: Re: [PATCH v6 08/11] tpm: Driver for supporting multiple emulated TPMs Date: Wed, 9 Mar 2016 21:34:47 -0500 Message-ID: <56E0DD47.50208@linux.vnet.ibm.com> References: <1457545170-30120-1-git-send-email-stefanb@linux.vnet.ibm.com> <1457545170-30120-9-git-send-email-stefanb@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Andy Lutomirski Cc: Jarkko Sakkinen , Jason Gunthorpe , "linux-kernel@vger.kernel.org" , "linux-doc@vger.kernel.org" , Linux API List-Id: linux-api@vger.kernel.org On 03/09/2016 01:01 PM, Andy Lutomirski wrote: > On Wed, Mar 9, 2016 at 9:39 AM, Stefan Berger > wrote: >> This patch implements a driver for supporting multiple emulated TPMs in a >> system. >> >> The driver implements a device /dev/vtpmx that is used to created >> a client device pair /dev/tpmX (e.g., /dev/tpm10) and a server side that >> is accessed using a file descriptor returned by an ioctl. >> The device /dev/tpmX is the usual TPM device created by the core TPM >> driver. Applications or kernel subsystems can send TPM commands to it >> and the corresponding server-side file descriptor receives these >> commands and delivers them to an emulated TPM. > Nifty! > > Is anyone considering writing a modification or replacement of > trousers that creates claims the real tpm and exposes a vtpm that > handles multiplexing internally? Does the vtpm driver intelligently > support multiple simultaneous clients? The vtpm driver allows to use an independent trousers instance in each container. Using the VTPM_NEW_DEV ioctl the container mgmt. stack can create a /dev/tpmX (X=0,1,2,...) device and a file descriptor. The file descriptor is passed to a vTPM instance, the /dev/tpmX is moved into the container, meaning a device with the same major/minor numbers is created in the container. This then allows each container to talk to an independent vTPM. The vTPM can either be 1.2 or 2. Stefan > > --Andy > -- > To unsubscribe from this list: send the line "unsubscribe linux-doc" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >