USB: Fix race condition when removing host controllers

[firefly-linux-kernel-4.4.55.git] / drivers / usb / core / hcd.c

diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 190b1ec7bdcbba1d3881421cd91b1195fea4808e..75ba2091f9b4f253a699563e22a9c6fd80c12676 100644 (file)
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -1011,10 +1011,7 @@ static int register_root_hub(struct usb_hcd *hcd)
        if (retval) {
                dev_err (parent_dev, "can't register root hub for %s, %d\n",
                                dev_name(&usb_dev->dev), retval);
-       }
-       mutex_unlock(&usb_bus_list_lock);
-
-       if (retval == 0) {
+       } else {
                spin_lock_irq (&hcd_root_hub_lock);
                hcd->rh_registered = 1;
                spin_unlock_irq (&hcd_root_hub_lock);
@@ -1023,6 +1020,7 @@ static int register_root_hub(struct usb_hcd *hcd)
                if (HCD_DEAD(hcd))
                        usb_hc_died (hcd);      /* This time clean up */
        }
+       mutex_unlock(&usb_bus_list_lock);
 
        return retval;
 }
@@ -1398,7 +1396,15 @@ int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
            && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
                if (hcd->self.uses_dma) {
                        if (urb->num_sgs) {
-                               int n = dma_map_sg(
+                               int n;
+
+                               /* We don't support sg for isoc transfers ! */
+                               if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
+                                       WARN_ON(1);
+                                       return -EINVAL;
+                               }
+
+                               n = dma_map_sg(
                                                hcd->self.controller,
                                                urb->sg,
                                                urb->num_sgs,