Re: [PATCH v4 06/10] KVM: selftests: Add support for vcpu_args_set to aarch64 and s390x

Christian Borntraeger
2020-01-24T18:33:49Z

On 24.01.20 10:03, Paolo Bonzini wrote:
> CCing Marc, Conny and Christian (plus Thomas and Drew who were already
> in the list) for review.

CC Thomas Huth,

>
> Thanks,
>
> Paolo
>
> On 23/01/20 19:04, Ben Gardon wrote:
>> Currently vcpu_args_set is only implemented for x86. This makes writing
>> tests with multiple vCPUs difficult as each guest vCPU must either a.)
>> do the same thing or b.) derive some kind of unique token from it's
>> registers or the architecture. To simplify the process of writing tests
>> with multiple vCPUs for s390 and aarch64, add set args functions for
>> those architectures.
[...]
>> .../selftests/kvm/lib/s390x/processor.c | 35 +++++++++++++++++++
[...]
>> --- a/tools/testing/selftests/kvm/lib/s390x/processor.c
>> +++ b/tools/testing/selftests/kvm/lib/s390x/processor.c
>> @@ -269,6 +269,41 @@ void vm_vcpu_add_default(struct kvm_vm *vm, uint32_t vcpuid, void *guest_code)
>> run->psw_addr = (uintptr_t)guest_code;
>> }
>>
>> +/* VM VCPU Args Set
>> + *
>> + * Input Args:
>> + * vm - Virtual Machine
>> + * vcpuid - VCPU ID
>> + * num - number of arguments
>> + * ... - arguments, each of type uint64_t
>> + *
>> + * Output Args: None
>> + *
>> + * Return: None
>> + *
>> + * Sets the first num function input arguments to the values
>> + * given as variable args. Each of the variable args is expected to
>> + * be of type uint64_t. The registers set by this function are r2-r6.
>> + */
>> +void vcpu_args_set(struct kvm_vm *vm, uint32_t vcpuid, unsigned int num, ...)
>> +{
>> + va_list ap;
>> + struct kvm_regs regs;
>> +
>> + TEST_ASSERT(num >= 1 && num <= 5, "Unsupported number of args,\n"
>> + " num: %u\n",
>> + num);
>> +
>> + va_start(ap, num);
>> + vcpu_regs_get(vm, vcpuid, &regs);
>> +
>> + for (i = 0; i < num; i++)
>> + regs.gprs[i + 2] = va_arg(ap, uint64_t);
>> +
>> + vcpu_regs_set(vm, vcpuid, &regs);
>> + va_end(ap);
>> +}
>> +
>> void vcpu_dump(FILE *stream, struct kvm_vm *vm, uint32_t vcpuid, uint8_t indent)
>> {
>> struct vcpu *vcpu = vm->vcpu_head;
>>
>

Untested but the logic looks sane according to the ELF ABI.