usb: core: hub: fix race condition about TRSMRCY of resume

This may happen if the port becomes resume status exactly when usb_port_resume() gets port status, it still need provide a TRSMCRY time before access the device. CC: <[email protected]> Reported-by: Tianping Fang <[email protected]> Acked-by: Alan Stern <[email protected]> Signed-off-by: Chunfeng Yun <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
simonjhall · May 13, 2021 · 975f94c · 975f94c
1 parent 12701ce
commit 975f94c
Showing 1 changed file with 3 additions and 3 deletions.
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
@@ -3642,9 +3642,6 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg)
 		 * sequence.
 		 */
 		status = hub_port_status(hub, port1, &portstatus, &portchange);
-
-		/* TRSMRCY = 10 msec */
-		msleep(10);
 	}
 
  SuspendCleared:
@@ -3659,6 +3656,9 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg)
 				usb_clear_port_feature(hub->hdev, port1,
 						USB_PORT_FEAT_C_SUSPEND);
 		}
+
+		/* TRSMRCY = 10 msec */
+		msleep(10);
 	}
 
 	if (udev->persist_enabled)