kcov testing uncovered call to usb_hcd_giveback_urb() without disabling
interrupts.

Link: 
https://lore.kernel.org/linux-usb/CAAeHK+wb4k-LGTjK9F5YbJNviF_+yU+wE_=vpo9rn7kfn8v...@mail.gmail.com/

usb_hcd_giveback_urb() is called from vhci's urb_enqueue, when it
determines it doesn't need to xmit the urb and can give it back.
This path runs in task context.

Disable irqs around usb_hcd_giveback_urb() call.

Reported-by: Andrey Konovalov <andreyk...@google.com>
Suggested-by: Alan Stern <st...@rowland.harvard.edu>
Signed-off-by: Shuah Khan <sk...@linuxfoundation.org>
---

Changes in v2: Changelog updated with correct information.
 drivers/usb/usbip/vhci_hcd.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/usbip/vhci_hcd.c b/drivers/usb/usbip/vhci_hcd.c
index 1b598db5d8b9..66cde5e5f796 100644
--- a/drivers/usb/usbip/vhci_hcd.c
+++ b/drivers/usb/usbip/vhci_hcd.c
@@ -797,8 +797,14 @@ static int vhci_urb_enqueue(struct usb_hcd *hcd, struct 
urb *urb, gfp_t mem_flag
        usb_hcd_unlink_urb_from_ep(hcd, urb);
 no_need_unlink:
        spin_unlock_irqrestore(&vhci->lock, flags);
-       if (!ret)
+       if (!ret) {
+               /* usb_hcd_giveback_urb() should be called with
+                * irqs disabled
+                */
+               local_irq_disable();
                usb_hcd_giveback_urb(hcd, urb, urb->status);
+               local_irq_enable();
+       }
        return ret;
 }
 
-- 
2.25.1

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