KVM: x86: hyper-v: Honor HV_X64_CLUSTER_IPI_RECOMMENDED bit

Hyper-V partition must possess 'HV_X64_CLUSTER_IPI_RECOMMENDED'
privilege ('recommended' is rather a misnomer) to issue
HVCALL_SEND_IPI hypercalls.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210521095204.2161214-27-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/hyperv.c

@@ -2118,6 +2118,10 @@ static bool hv_check_hypercall_access(struct kvm_vcpu_hv *hv_vcpu, u16 code)
 	case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
 		return hv_vcpu->cpuid_cache.enlightenments_eax &
 			HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED;
+	case HVCALL_SEND_IPI_EX:
+	case HVCALL_SEND_IPI:
+		return hv_vcpu->cpuid_cache.enlightenments_eax &
+			HV_X64_CLUSTER_IPI_RECOMMENDED;
 	default:
 		break;
 	}