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SubjectRe: [PATCH 3/3] vTPM: support little endian guests
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Thanks Ashley!

> > The event log in ppc64 arch is always in big endian format. PowerPC
> > supports both little endian and big endian guests. This patch converts
> > the event log entries to guest format.
>
> I'm a little confused here. If this patch is to convert the event log
> entries why are we convert in the conditional statements? One example
> below:
>
> + if (((convert_to_host_format(event->event_type) == 0) &&
> + (convert_to_host_format(event->event_size) == 0))
> + ||
> + ((v + sizeof(struct tcpa_event) +
> + convert_to_host_format(event->event_size)) > limit))
>
> >
> > We defined a macro to convert to guest format. In addition,
> > tpm_binary_bios_measurements_show() is modified to parse the event
> > and print each field individually.
>

We do not convert the whole event entry. Instead, we're converting only
what's necessary such as pcr_index, event_type and event_size. pcr_value
and event_data are of type u8. They do not need LE conversion.


> It's nice to have human readable format but it may break existing tools
> that parse or understand the machine readable format. Any comments on
> this anyone?

I got comments on the format, so I tried to make that conditional
statement all in one line, but the 'Lindent' tool puts the lines back to
the above format..


Regards,
Vicky



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