Re: [PATCH] KVM: selftests: x86: clarify what is reported on KVM_GET_MSRS failure

[Paolo Bonzini]

On 27/09/19 17:54, Vitaly Kuznetsov wrote:
> When KVM_GET_MSRS fail the report looks like
> 
> ==== Test Assertion Failure ====
>   lib/x86_64/processor.c:1089: r == nmsrs
>   pid=28775 tid=28775 - Argument list too long
>      1	0x000000000040a55f: vcpu_save_state at processor.c:1088 (discriminator 3)
>      2	0x00000000004010e3: main at state_test.c:171 (discriminator 4)
>      3	0x00007fb8e69223d4: ?? ??:0
>      4	0x0000000000401287: _start at ??:?
>   Unexpected result from KVM_GET_MSRS, r: 36 (failed at 194)
> 
> and it's not obvious that '194' here is the failed MSR index and that
> it's printed in hex. Change that.
> 
> Suggested-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
> Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
> ---
>  tools/testing/selftests/kvm/lib/x86_64/processor.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
> index c53dbc6bc568..6698cb741e10 100644
> --- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
> +++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
> @@ -1085,7 +1085,7 @@ struct kvm_x86_state *vcpu_save_state(struct kvm_vm *vm, uint32_t vcpuid)
>  	for (i = 0; i < nmsrs; i++)
>  		state->msrs.entries[i].index = list->indices[i];
>  	r = ioctl(vcpu->fd, KVM_GET_MSRS, &state->msrs);
> -        TEST_ASSERT(r == nmsrs, "Unexpected result from KVM_GET_MSRS, r: %i (failed at %x)",
> +        TEST_ASSERT(r == nmsrs, "Unexpected result from KVM_GET_MSRS, r: %i (failed MSR was 0x%x)",
>                  r, r == nmsrs ? -1 : list->indices[r]);
>  
>  	r = ioctl(vcpu->fd, KVM_GET_DEBUGREGS, &state->debugregs);
> 

Queued, thanks.

Paolo