Re: [PATCH v1 1/4] xsm/libxl/xen_version: Add XSM for some of the xen_version commands.

[Martin Pohlack <mpohlack@amazon.com>]

On 09.10.2015 11:31, Ian Campbell wrote:
> On Thu, 2015-10-08 at 22:56 -0400, Konrad Rzeszutek Wilk wrote:
>> The XENVER_[compile_info|changeset|commandline] are now
>> guarded by an XSM check.
> 
> I can guess, but please explain/justify why this is the case for these
> here.
> 
>> The rest: XENVER_[version|extraversion|capabilities|
>> parameters|get_features|page_size|guest_handle] behave
>> as before (no XSM check).
> 
> and correspondingly why these ones to not warrant such a change.
>
>> As such we also modify the toolstack such that if we fail
>> to get any data instead of printing (null) we just print "".
> 
> Perhaps the hypervisor should instead return "<denied>" or some suitable
> string indicating why (<denied-xsm>)?

Yes, that makes it more obvious to userland what is going on and when
debugging and might limit userland breakage where at least some string
is required.

Martin
Amazon Development Center Germany GmbH
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