Jon Doron <arilou@xxxxxxxxx> writes:
> There is another mode for the synthetic debugger which uses hypercalls
> to send/recv network data instead of the MSR interface.
>
> This interface is much slower and less recommended since you might get
> a lot of VMExits while KDVM polling for new packets to recv, rather
> than simply checking the pending page to see if there is data avialble
> and then request.
>
> Signed-off-by: Jon Doron <arilou@xxxxxxxxx>
> ---
> arch/x86/kvm/hyperv.c | 22 ++++++++++++++++++++++
> 1 file changed, 22 insertions(+)
>
> diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
> index 917b10a637fc..4a77ff61658b 100644
> --- a/arch/x86/kvm/hyperv.c
> +++ b/arch/x86/kvm/hyperv.c
> @@ -1821,6 +1821,28 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
> }
> ret = kvm_hv_send_ipi(vcpu, ingpa, outgpa, true, false);
> break;
> + case HVCALL_POST_DEBUG_DATA:
> + case HVCALL_RETRIEVE_DEBUG_DATA:
> + if (unlikely(fast)) {
> + ret = HV_STATUS_INVALID_PARAMETER;
> + break;
> + }
> + /* fallthrough */
This is now being changed to 'fallthrough;'
> + case HVCALL_RESET_DEBUG_SESSION: {
> + struct kvm_hv_syndbg *syndbg = vcpu_to_hv_syndbg(vcpu);
> + if (!(syndbg->options & HV_X64_SYNDBG_OPTION_USE_HCALLS)) {
> + ret = HV_STATUS_OPERATION_DENIED;
> + break;
> + }
> + vcpu->run->exit_reason = KVM_EXIT_HYPERV;
> + vcpu->run->hyperv.type = KVM_EXIT_HYPERV_HCALL;
> + vcpu->run->hyperv.u.hcall.input = param;
> + vcpu->run->hyperv.u.hcall.params[0] = ingpa;
> + vcpu->run->hyperv.u.hcall.params[1] = outgpa;
> + vcpu->arch.complete_userspace_io =
> + kvm_hv_hypercall_complete_userspace;
> + return 0;
> + }
> default:
> ret = HV_STATUS_INVALID_HYPERCALL_CODE;
> break;
And the hypercall should also check whether KVM_CAP_HYPERV_DEBUGGING is
enabled.
--
Vitaly
