diff --git a/OvmfPkg/Library/VirtioMmioDeviceLib/VirtioMmioDevice.h b/OvmfPkg/Library/VirtioMmioDeviceLib/VirtioMmioDevice.h
index 785876c75f..ab53b90d51 100644
--- a/OvmfPkg/Library/VirtioMmioDeviceLib/VirtioMmioDevice.h
+++ b/OvmfPkg/Library/VirtioMmioDeviceLib/VirtioMmioDevice.h
@@ -107,6 +107,7 @@ VirtioMmioSetQueueSel (
   );
 
 EFI_STATUS
+EFIAPI
 VirtioMmioSetQueueAddress (
   IN VIRTIO_DEVICE_PROTOCOL  *This,
   IN VRING                   *Ring,
diff --git a/OvmfPkg/Library/VirtioMmioDeviceLib/VirtioMmioDeviceFunctions.c b/OvmfPkg/Library/VirtioMmioDeviceLib/VirtioMmioDeviceFunctions.c
index 454f008827..b0d75fb1dd 100644
--- a/OvmfPkg/Library/VirtioMmioDeviceLib/VirtioMmioDeviceFunctions.c
+++ b/OvmfPkg/Library/VirtioMmioDeviceLib/VirtioMmioDeviceFunctions.c
@@ -173,6 +173,7 @@ VirtioMmioSetQueueSel (
 }
 
 EFI_STATUS
+EFIAPI
 VirtioMmioSetQueueAddress (
   IN VIRTIO_DEVICE_PROTOCOL  *This,
   IN VRING                   *Ring,