Re: [RFC kvm-unit-tests PATCH] powerpc: add tests for XICS

[Laurent Vivier <lvivier@redhat.com>]

On 13/10/2017 11:45, Thomas Huth wrote:
> On 12.10.2017 10:07, Laurent Vivier wrote:
>> Check if we can set the xive server and priority, and
>> check we get values that have been set.
>> Check we disable/enable interrupts.
>>
>> This patch also increases NR_CPUS from 8 to 16
>> (maximum for KVM on POWER9, POWER8 allows 96)
>>
>> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
>> ---
>> Note: I send this as an RFC, because even if this test works well with
>> TCG and POWER8 KVM hosts, it detects some problems with POWER9 KVM hosts
> 
> What kind of errors does it detect? Are they expected due to the
> different interrupt controllers?
> 

[I cc' Sam as he already did a fix for this part in the kernel]

I have two kinds of error:

- "xics: get-xive: irq #4351, expected cpu 15 prio 255, had cpu 0 prio
   255",
  Priority 255 is set to disable the IRQs, I don't think it's really a
  problem at this level, it could be only cosmetic,

- "xics: int-on: irq #4351, ret = -3",
  but here it becomes more serious: as the IRQ server has been lost, it
  seems we are not able to re-enable the interrupt.

I have no access to a POWER9 host to debug this at the kernel level for
the moment, so I can't do more.

Thanks,
Laurent