From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarkko Sakkinen Subject: Re: [PATCH v8 08/10] tpm: Proxy driver for supporting multiple emulated TPMs Date: Wed, 16 Mar 2016 22:37:50 +0200 Message-ID: <20160316203750.GA23966@intel.com> References: <1457909680-14085-1-git-send-email-stefanb@linux.vnet.ibm.com> <1457909680-14085-9-git-send-email-stefanb@linux.vnet.ibm.com> <20160316120916.GA14820@intel.com> <20160316174904.GA6127@obsidianresearch.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20160316174904.GA6127-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org> Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Jason Gunthorpe Cc: Stefan Berger , tpmdd-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, linux-security-module-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-doc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, dhowells-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org List-Id: tpmdd-devel@lists.sourceforge.net On Wed, Mar 16, 2016 at 11:49:04AM -0600, Jason Gunthorpe wrote: > On Wed, Mar 16, 2016 at 02:09:16PM +0200, Jarkko Sakkinen wrote: > > On Sun, Mar 13, 2016 at 06:54:38PM -0400, Stefan Berger wrote: > > > Alternative to this would be to have /dev/vtpmx create: > > > > * /dev/vtpm0 for the server > > * /dev/tpm0 for the client > > > > This is how David Howell's PoC worked and that's why I want > > to make this alternative visible. > > > > The server could even respawn without container noticing it. > > This solution have better availability properties. > > Seriously, no, that doesn't make any sense. TPM is stateful, you can't > respawn the server side. > > If anyone is ever clever enough to make that workable then they just > go ahead and save the server fd with the other state. systemd for > instance already has everything needed to make that work. > > We don't need to have a server dev node and we certainly don't need > the leaking problem that leaves us with. Fair enough. > Jason /Jarkko