Re: [Qemu-devel] [PATCH v2] Add ACPI tables for TPM

[Laszlo Ersek <lersek@redhat.com>]

On 07/30/14 18:35, Stefan Berger wrote:
> Laszlo Ersek <lersek@redhat.com> wrote on 07/30/2014 12:18:02 PM:
> 
>> From: Laszlo Ersek <lersek@redhat.com>
>> To: "Michael S. Tsirkin" <mst@redhat.com>, Stefan Berger/Watson/IBM@IBMUS
>> Cc: qemu-devel@nongnu.org, Stefan Berger <stefanb@linux.vnet.ibm.com>
>> Date: 07/30/2014 12:18 PM
>> Subject: Re: [PATCH v2] Add ACPI tables for TPM
>>
>> On 07/30/14 18:10, Michael S. Tsirkin wrote:
>> > On Wed, Jul 30, 2014 at 12:03:46PM -0400, Stefan Berger wrote:
>> >> Laszlo Ersek <lersek@redhat.com> wrote on 07/30/2014 11:58:52 AM:
>>
>> >>> In the short term, probably skip TCPA, or advise users in
> documentation
>> >>> not to enable the TPM device when running OVMF.
>> >
>> > Hmm but doesn't OVMF rely on all tables being packed without holes
>> > in memory?
>> > I remember it did, and if it still does, this breaks unless TCPA is
>> > the last ...
>>
>> Ah, do you mean that the table size field in the ACPI table header of
>> TCPA would *not* include the TCG event log that is tacked-on? Yes, that
>> would certainly trip up the parser. It advances by looking at the table
>> size fields in the headers.
> 
> Is this what finally requires another command for the linker/loader to
> allocate a chunk of memory where the size of the to-be-allocated memory
> is found
> at the location of the pointer ?

No, the above is a limitation of the current OVMF parser.

Thanks
Laszlo