Re: [PATCH mini-os enhancements for vtpm 8/8] Add 3 tpm drivers to mini-os

[Ian Campbell <Ian.Campbell@citrix.com>]

On Mon, 2012-09-17 at 23:08 +0100, Matthew Fioravante wrote:
> This patch adds 3 new drivers to mini-os.
> 
> tpmfront - paravirtualized tpm frontend driver
> tpmback - paravirtualized tpm backend driver
> tpm_tis - hardware tpm driver
> 
> Unfortunately these drivers were derived from GPL licensed linux kernel
> drivers so they must carry the GPL license.

I notice that you have used GPL v3 here, while the original Linux
versions of these files (I looked at 3.6-rc3)both say:
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation, version 2 of the
 * License.
i.e. doesn't contain the "or later" wording which would allow an upgrade
to v3. Did all of the copyright holders agree to this relicensing?

>  However, since mini-os now
> supports conditional compilation, hopefully these drivers can be
> included into the xen tree and conditionally removed from non-gpl
> projects. By default they are disabled in the makefile.

Are these drivers useful for other stub domains generally or are they
only really useful in the vtpm stub domains? IOW could this GPL code be
made part of the application instead?

This would allow better segregation between the BSD bits of mini-os and
GPL bits.

> Signed off by: Matthew Fioravante matthew.fioravante@jhuapl.edu

Can you confirm that you have the right to submit his code under this
license, since you are not listed in the copyright I guess that would be
clause B of the DCO:
http://wiki.xen.org/wiki/Submitting_Xen_Patches#Signing_off_a_patch

> diff --git a/extras/mini-os/include/tpm_tis.h
> b/extras/mini-os/include/tpm_tis.h
> --- /dev/null
> +++ b/extras/mini-os/include/tpm_tis.h
> @@ -0,0 +1,63 @@
> +/*
> + * Copyright (c) 2010-2012 United States Government, as represented by
> + * the Secretary of Defense.  All rights reserved.
> + *
> + * This driver is free software: you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation, either version 3 of the License, or
> + * (at your option) any later version.
> + *
> + * This driver is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program.  If not, see <http://www.gnu.org/licenses/>.
> + *
> + * Based upon the files:
> + *  drivers/char/tpm/tpm_tis.c
> + *  drivers/char/tpm/tpm.c
> + * from the Linux kernel, which are Copyright (C) 2006 IBM Corporation
> + */