Re: [libvirt] [PATCH v3 1/9] qemu: provide support to query the SEV capability
On 03/26/2018 09:32 AM, Andrea Bolognani wrote:
On Mon, 2018-03-26 at 08:52 -0500, Brijesh Singh wrote:
>> I tried applying just this patch, but kept getting:
>>
>> 29) caps_2.12.0(x86_64)
>> ... libvirt: QEMU Driver error : internal error: query-cpu-definitions
>> reply data was not an array
>>
>> a small bit of debugging found that qemuMonitorJSONGetCPUDefinitions was
>> returning NULL for @data after/when the "query-sev-capabilities".
>>
>> I narrowed it down into the virQEMUCapsInitQMPMonitor when run during
>> qemucapabilitiestest (see [1])
>
> I have not tried latest libvirt yet, I will try this today and debug to
> see what we are missing. I did the 'make check' before submitting the
> patch but at that time QEMU 2.12 was not available and we did not had
> updated caps_2.12.0.x86_64.xml and caps_2.12.0.x86_64.replies.
I thought the lack of churn in tests/qemucapabilitiesdata/ was
weird, but thanks to your explanation it makes perfect sense now.
Your code adds a call to query-sev-capabilities, but the replies
file doesn't contain the corresponding return data, which makes
the parser go out of sync.
You're going to have to either fetch capabilities from your own
QEMU 2.12 binary or hack it up by adding the return data in the
right spot and call tests/qemucapsfixreplies to re-align the ids.
Right, running the tests/qemucapsprobe on my system I see that
query-sev-capabilities command returns a valid data. In my local branch,
I updated the caps_2.12.0.x86_64.replies with response. With those
changes I no longer get the internal error but
tests/qemucapabilitiestest still fails for me with below error message:
29) caps_2.12.0(x86_64) ...
In
'/home/amd/workdir/upstream/libvirt/tests/qemucapabilitiesdata/caps_2.12.0.x86_64.xml':
Offset 7143
Expect [060]
Actual [306]
It is basically pointing to microcode version change, do I need to
update the cap with new version ?
I think you can get away with the latter, as we're going to want
to refresh the replies files once 2.12 is released anyway.
I am not able to follow this comment, let me explain the situation.
The QEMU_CAPS_SEV flag was set to indicate QEMU supports the
'query-sev-capabilities' QMP command and sev-guest object. That merely
indicates that command exist but does not means that command will always
execute successfully. e.g If hypervisor does not support the SEV feature
then query-sev-capabilities will return error. That means if
tests/qemucapsprobe is used to generate the replies on non-SEV capable
system then .replies will not contain output of query-sev-capabilities
command. Will this be an issue ?
-Brijesh