diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index b1c0c707d96ccc6e713042b1d67167609199c723..194f1d21d3d784d3ce73301acf42ff5c38240e32 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -264,6 +264,13 @@ static int pci_device_remove(struct device * dev)
 		pci_dev->driver = NULL;
 	}
 
+	/*
+	 * If the device is still on, set the power state as "unknown",
+	 * since it might change by the next time we load the driver.
+	 */
+	if (pci_dev->current_state == PCI_D0)
+		pci_dev->current_state = PCI_UNKNOWN;
+
 	/*
 	 * We would love to complain here if pci_dev->is_enabled is set, that
 	 * the driver should have called pci_disable_device(), but the
@@ -288,6 +295,12 @@ static int pci_device_suspend(struct device * dev, pm_message_t state)
 		suspend_report_result(drv->suspend, i);
 	} else {
 		pci_save_state(pci_dev);
+		/*
+		 * mark its power state as "unknown", since we don't know if
+		 * e.g. the BIOS will change its device state when we suspend.
+		 */
+		if (pci_dev->current_state == PCI_D0)
+			pci_dev->current_state = PCI_UNKNOWN;
 	}
 	return i;
 }