[PATCH] cpu_map: Add more -noTSX x86 CPU models

[Christian Ehrhardt]

> ...
>
> Running make check would reveal all these issues because every single
> test which involves parsing the cpu_map was failing due to multiple
> definitions of the same CPU model.
>
> I'd not have expected that the tests will exercise the new XMLs in any way.
Good to know and thanks for your feedback.


> And since this patch is adding several CPU models which are already
> supported by QEMU since 4.2.0, you need to update several existing test
> files for domaincapstest too. You can use
>
>     VIR_TEST_REGENERATE_OUTPUT=1 tests/domaincapstest
>
> to regenerate the files. Just make sure you review the changes before
> adding them to this commit.
>

Without regenerating these I see as expected
FAIL: domaincapstest
FAIL: cputest

Adding these 5 types to the qemu 4.2 and qemu 5.0
tests/domaincapsdata worked.
I've squashed that into the same patch - let me know if you'd prefer the
domaincapsdata change as an individual patch instead.

Regenerating the test files will also be needed for cputest because I
> just pushed the "cputest: Add data for Intel(R) Core(TM) i7-8550U CPU
> without TSX". Doing so will nicely show that the computed host CPU model
> (in x86_64-cpuid-Core-i7-8550U-host.xml file) is
> Skylake-Client-noTSX-IBRS rather than Broadwell-noTSX-IBRS.
>

Indeed:
1007 In
'/home/paelzer/work/libvirt/libvirt-ubuntu-git/build/../tests/cputestdata/x86_64-cpuid-Core-i7-8550U-host.xml':
...
1009 Expect [Broadwell-noTSX-IBRS</model>
...
1043 Actual [Skylake-Client-noTSX-IBRS</model>


> However, the CPU used for host-model (and reported in domain
> capabilities) as shown in x86_64-cpuid-Core-i7-8550U-guest.xml and
> x86_64-cpuid-Core-i7-8550U-json.xml will change from Skylake-Client-IBRS
> to Skylake-Client-noTSX-IBRS. As I said in my previous reply to this
> patch, I think these two CPU definitions should keep using the old
> Skylake-Client-IBRS model to make sure any domain with host-model CPU
> will always use the CPU models without noTSX for better compatibility
> between current and future version of libvirt.


I see three changes:
x86_64-cpuid-Core-i7-8550U-host.xml: Broadwell-noTSX-IBRS ->
Skylake-Client-noTSX-IBRS
x86_64-cpuid-Core-i7-8550U-guest.xml: Skylake-Client-IBRS ->
Skylake-Client-noTSX-IBRS
This shows up twice in:
238) cpuTestGuestCPUID(x86_64): Core-i7-8550U
240) cpuTestGuestCPUID(x86_64): Core-i7-8550U
x86_64-cpuid-Core-i7-8550U-json.xml: Skylake-Client-IBRS ->
Skylake-Client-noTSX-IBRS

So far so good and as expected.
But I have to beg your pardon and need to ask where such an override to
continue to use
"Skylake-Client-IBRS + policy='disable' name='hle' policy='disable'
name='rtm'" instead of just "Skylake-Client-noTSX-IBRS" would have to go?

Holding back v2 submission until this is solved ...

This change should be in
> a separate patch, but in single series with the current patch.
>
> Jirka
>
>

-- 
Christian Ehrhardt
Staff Engineer, Ubuntu Server
Canonical Ltd
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