fix(pci): correctly set device status to 0 on reset

Even though currently, no device supports resetting, when the guest
attempts to reset the device we must set the status to 0 as
specified in the 2.4.1 Device Requirements: Device Reset.

This does not change the current status of us not supporting device
resetting. This is the issue we encountered during addition of
virtio-pmem device where the guest kernel now resets devices on VM
shutdown.

Signed-off-by: Egor Lazarchuk <[email protected]>

Author: ShadowCurse

src/vmm/src/devices/virtio/transport/pci/device.rs

@@ -962,11 +962,12 @@ impl PciDevice for VirtioPciDevice {
                 }
                 None => {
                     error!("Attempt to reset device when not implemented in underlying device");
-                    self.common_config.driver_status = DEVICE_FAILED;
+                    // TODO: currently we don't support device resetting, but we still
+                    // follow the spec and set the status field to 0.
+                    self.common_config.driver_status = DEVICE_INIT;
                 }
             }
         }
-
         None
     }
 }