[kvm-unit-tests PATCH 14/32] powerpc: general interrupt tests

[Thomas Huth]

On 05/03/2024 03.19, Nicholas Piggin wrote:
> On Fri Mar 1, 2024 at 10:41 PM AEST, Thomas Huth wrote:
>> On 26/02/2024 11.12, Nicholas Piggin wrote:
>>> Add basic testing of various kinds of interrupts, machine check,
>>> page fault, illegal, decrementer, trace, syscall, etc.
>>>
>>> This has a known failure on QEMU TCG pseries machines where MSR[ME]
>>> can be incorrectly set to 0.
>>
>> Two questions out of curiosity:
>>
>> Any chance that this could be fixed easily in QEMU?
> 
> Yes I have a fix on the mailing list. It should get into 9.0 and
> probably stable.

Ok, then it's IMHO not worth the effort to make the k-u-t work around this 
bug in older QEMU versions.

>> Or is there a way to detect TCG from within the test? (for example, we have
>> a host_is_tcg() function for s390x so we can e.g. use report_xfail() for
>> tests that are known to fail on TCG there)
> 
> I do have a half-done patch which adds exactly this.
> 
> One (minor) annoyance is that it doesn't seem possible to detect QEMU
> version to add workarounds. E.g., we would like to test the fixed
> functionality, but older qemu should not. Maybe that's going too much
> into a rabbit hole. We *could* put a QEMU version into device tree
> to deal with this though...

No, let's better not do this - hardwired version checks are often a bad 
idea, e.g. when a bug is in QEMU 8.0.0 and 8.1.0, it could be fixed in 8.0.1 
and then it could get really messy with the version checks...

  Thomas