Re: [Qemu-devel] [PATCH v3 11/13] tests: acpi: add simple arm/virt testcase

[Wei Xu]

Hi Igor,

On 4/26/2019 12:54 PM, Igor Mammedov wrote:
> On Fri, 26 Apr 2019 00:51:56 +0800
> x00249684 <address@hidden> wrote:
> 
>> Hi Igor,
>>
>> +static void test_acpi_virt_tcg(void)
>> +{
>> +    test_data data = {
>> +        .machine = "virt",
>> +        .uefi_fl1 = "pc-bios/edk2-aarch64-code.fd",
>> +        .uefi_fl2 = "pc-bios/edk2-arm-vars.fd",
>> +        .cd = 
>> "tests/data/uefi-boot-images/bios-tables-test.aarch64.iso.qcow2",
>> +        .ram_start = 0x40000000ULL,
>> +        .scan_len = 128ULL * 1024 * 1024,
>> +    };
>> +
>> +    test_acpi_one("-cpu cortex-a57 ", &data);
>>
>> Replaced the cortex-a57 with host and succesfully tested on the hisilicon 
>> arm64 
>> D05 board. Otherwise it failed with "kvm_init_vcpu failed: Invalid argument".
>> Is it possilbe to set the cpu type like numa-test.c?
> 
> I think it works with numa-test because it uses TCG only but in case of 
> bios-tables-test
> it uses accel="kvm:tcg" to leverage KVM capabilities whenever possible to 
> speed up test.
> 
> Now back to our ARM test case, uefi requirement is to use 64bit CPU (hence it 
> was cortex-a57)
> however unlike x86 it obviously breaks since KVM accelerator on ARM host is 
> used
> and it doesn't work with anything other than 'host' cpu model.
> 
> I think we still want to use KVM whenever possible, but problem lies in that
> user (testcase) doesn't have an idea if KVM accelerator is available and host 
> is 64 CPU.
> 
> to sum up we need to support 2 modes:
>   1. host is 64 ARM, use kvm with -cpu host
>   2. all other cases use tcg with -cpu cortex-a57
> 
> I can hack to probe if /dev/kvm is accessible and host is 64 bit and use #1
> otherwise fallback to #2
> or as quick fix do only #2 initially and think about a better solution to #1 

Thanks!
Fine to me.

> 
> Is there any other suggestions/opinions how to approach issue/proceed.

To check the host cpu architecture is ARM or not, maybe we can check the value
of "CPU implementer" is 0x41 or not from the /proc/cpuinfo.

Best Regards,
Wei

> 
> PS:
> we probably would like to reuse this not only for acpi tests but also for 
> other
> arm/virt test cases that involve running guest code. 
> 
>> Thanks!
>>
>> Best Regards,
>> Wei
> 
> 
> .
>