2 files changed, 25 insertions, 11 deletions

diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index df661460e..59d5d506d 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -1805,7 +1805,6 @@ static void usb_giveback_urb_bh(unsigned long param)
 
 	spin_lock_irq(&bh->lock);
 	bh->running = true;
- restart:
 	list_replace_init(&bh->head, &local_list);
 	spin_unlock_irq(&bh->lock);
 
@@ -1819,10 +1818,17 @@ static void usb_giveback_urb_bh(unsigned long param)
 		bh->completing_ep = NULL;
 	}
 
-	/* check if there are new URBs to giveback */
+	/*
+	 * giveback new URBs next time to prevent this function
+	 * from not exiting for a long time.
+	 */
 	spin_lock_irq(&bh->lock);
-	if (!list_empty(&bh->head))
-		goto restart;
+	if (!list_empty(&bh->head)) {
+		if (bh->high_prio)
+			tasklet_hi_schedule(&bh->bh);
+		else
+			tasklet_schedule(&bh->bh);
+	}
 	bh->running = false;
 	spin_unlock_irq(&bh->lock);
 }
@@ -1847,7 +1853,7 @@ static void usb_giveback_urb_bh(unsigned long param)
 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
 {
 	struct giveback_urb_bh *bh;
-	bool running, high_prio_bh;
+	bool running;
 
 	/* pass status to tasklet via unlinked */
 	if (likely(!urb->unlinked))
@@ -1858,13 +1864,10 @@ void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
 		return;
 	}
 
-	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) {
+	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe))
 		bh = &hcd->high_prio_bh;
-		high_prio_bh = true;
-	} else {
+	else
 		bh = &hcd->low_prio_bh;
-		high_prio_bh = false;
-	}
 
 	spin_lock(&bh->lock);
 	list_add_tail(&urb->urb_list, &bh->head);
@@ -1873,7 +1876,7 @@ void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
 
 	if (running)
 		;
-	else if (high_prio_bh)
+	else if (bh->high_prio)
 		tasklet_hi_schedule(&bh->bh);
 	else
 		tasklet_schedule(&bh->bh);
@@ -2881,6 +2884,7 @@ int usb_add_hcd(struct usb_hcd *hcd,
 
 	/* initialize tasklets */
 	init_giveback_urb_bh(&hcd->high_prio_bh);
+	hcd->high_prio_bh.high_prio = true;
 	init_giveback_urb_bh(&hcd->low_prio_bh);
 
 	/* enable irqs just before we start the controller,
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 29cc2aa5a..d1a7f22cb 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -5851,6 +5851,11 @@ re_enumerate_no_bos:
  * the reset is over (using their post_reset method).
  *
  * Return: The same as for usb_reset_and_verify_device().
+ * However, if a reset is already in progress (for instance, if a
+ * driver doesn't have pre_reset() or post_reset() callbacks, and while
+ * being unbound or re-bound during the ongoing reset its disconnect()
+ * or probe() routine tries to perform a second, nested reset), the
+ * routine returns -EINPROGRESS.
  *
  * Note:
  * The caller must own the device lock.  For example, it's safe to use
@@ -5884,6 +5889,10 @@ int usb_reset_device(struct usb_device *udev)
 		return -EISDIR;
 	}
 
+	if (udev->reset_in_progress)
+		return -EINPROGRESS;
+	udev->reset_in_progress = 1;
+
 	port_dev = hub->ports[udev->portnum - 1];
 
 	/*
@@ -5948,6 +5957,7 @@ int usb_reset_device(struct usb_device *udev)
 
 	usb_autosuspend_device(udev);
 	memalloc_noio_restore(noio_flag);
+	udev->reset_in_progress = 0;
 	return ret;
 }
 EXPORT_SYMBOL_GPL(usb_reset_device);