From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Bottomley Subject: Re: [PATCH v2 6/7] tpm: expose spaces via a device link /dev/tpms Date: Fri, 24 Feb 2017 08:02:08 -0500 Message-ID: <1487941328.2249.23.camel@HansenPartnership.com> References: <20170216192529.25467-1-jarkko.sakkinen@linux.intel.com> <20170216192529.25467-7-jarkko.sakkinen@linux.intel.com> <20170223090917.jq7thil5ggjmagil@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20170223090917.jq7thil5ggjmagil-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tpmdd-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org To: Jarkko Sakkinen , tpmdd-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Cc: open list , dhowells-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, linux-security-module-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: tpmdd-devel@lists.sourceforge.net On Thu, 2017-02-23 at 11:09 +0200, Jarkko Sakkinen wrote: > On Thu, Feb 16, 2017 at 09:25:19PM +0200, Jarkko Sakkinen wrote: > > From: James Bottomley > > > > Currently the tpm spaces are not exposed to userspace. Make this > > exposure via a separate device, which can now be opened multiple > > times because each read/write transaction goes separately via the > > space. > > > > Concurrency is protected by the chip->tpm_mutex for each read/write > > transaction separately. The TPM is cleared of all transient > > objects by the time the mutex is dropped, so there should be no > > interference between the kernel and userspace. > > Signed-off-by: James Bottomley < > > > > James.Bottomley-d9PhHud1Jfhevp4ocFNHEFaTQe2KTcn/@public.gmane.org> > Reviewed-by: Jarkko Sakkinen > Tested-by: Jarkko Sakkinen Thanks! > Nitpicking but I've been thinking about naming. What about calling > the device as tpmrc0 as in resource context. I think that would be a > better name than TPM space. Well the original name was tpmrm for TPM with Resource Manager. You wanted it to be tpms for TPM with Spaces. I'm not entirely sold on the Resource Context name ... I think Resource Manager (because it's what the TCG calls it) or Spaces (because it's what all the code comments call it) are better. Resource Context sounds like what TPM2_SaveContext() creates for you rather than the interface. > You do not mix it up with namespaces and/or virtualization. With > resource in front it cannot be easily mixed up with TPM contexts > either. I'm a containers person. What this set of patches does is precisely OS level virtualization in my book, so I don't think you need to pretend it is't; and OS level virtualization is what a namespace does. The only difference between this and the other kernel namespaces is that you get a new namespace automatically when you open the device and you can't enter an existing namespace. I think therefore that tpmns for TPM Namespace would be very appropriate. > This does not require any effort from your side. I could do the > renaming. > > PS. Could you go through my commits and test and review them at some > point so we would have the whole patch set peer tested? Already reviewed, just doing a test build (I'm travelling, so it actually has to be on my physical laptop). James ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot