Re: [PATCH 1/9] tests/qtest/arm-cpu-features: Remove Cortex-A15 check

[Philippe Mathieu-Daudé]

Hi Drew,

On 2/5/21 3:59 PM, Andrew Jones wrote:
> On Fri, Feb 05, 2021 at 03:43:37PM +0100, Philippe Mathieu-Daudé wrote:
>> Support for ARMv7 has been dropped in commit 82bf7ae84ce
>> ("target/arm: Remove KVM support for 32-bit Arm hosts"),
>> no need to check for Cortex A15 host cpu anymore.
>>
>> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
>> ---
>>  tests/qtest/arm-cpu-features.c | 4 ----
>>  1 file changed, 4 deletions(-)
>>
>> diff --git a/tests/qtest/arm-cpu-features.c b/tests/qtest/arm-cpu-features.c
>> index 8252b85bb85..c59c3cb002b 100644
>> --- a/tests/qtest/arm-cpu-features.c
>> +++ b/tests/qtest/arm-cpu-features.c
>> @@ -515,10 +515,6 @@ static void test_query_cpu_model_expansion_kvm(const 
>> void *data)
>>          QDict *resp;
>>          char *error;
>>  
>> -        assert_error(qts, "cortex-a15",
>> -            "We cannot guarantee the CPU type 'cortex-a15' works "
>> -            "with KVM on this host", NULL);
>> -
> 
> This isn't testing anything regarding 32-bit KVM host support. It's
> testing that an error is returned when a given cpu type that can't
> be known to work with KVM is used. We know that the cortex-a15 can't
> be known to work. If we were to use a 64-bit cpu type here then there's
> a chance that it would work, failing the test that an error be returned.

This was my first understanding, but then why does it fail?

PASS 1 qtest-aarch64/arm-cpu-features /aarch64/arm/query-cpu-model-expansion
**
ERROR:../../tests/qtest/arm-cpu-features.c:543:test_query_cpu_model_expansion_kvm:
assertion failed: (g_str_equal(_error, "We cannot guarantee the CPU type
'cortex-a15' works " "with KVM on this host"))
ERROR qtest-aarch64/arm-cpu-features - Bail out!
ERROR:../../tests/qtest/arm-cpu-features.c:543:test_query_cpu_model_expansion_kvm:
assertion failed: (g_str_equal(_error, "We cannot guarantee the CPU type
'cortex-a15' works " "with KVM on this host"))
make: *** [Makefile.mtest:905: run-test-111] Error 1

FWIW when tracing (cavium thunderX1 host, dmesg reports 0x431f0a11):
kvm_vcpu_ioctl cpu_index 0, type 0x4020aeae, arg 0xffff9b7f9b18

> 
>>          assert_has_feature_enabled(qts, "host", "aarch64");
>>  
>>          /* Enabling and disabling pmu should always work. */
>> -- 
>> 2.26.2
>>
>>
> 
> This file could use a cleanup patch regarding the dropping of 32-bit KVM
> support though. At least the comment in main(), "For now we only run KVM
> specific tests..." could be reworded. It was written that way when we
> planned to try testing on 32-bit KVM too eventually, but we never did,
> and now we'll never need to.
> 
> Thanks,
> drew
> 
>