commit 2f02bc8af3abb846823811af65ec6cc46a4d525d
Author: Alan Stern <stern@rowland.harvard.edu>
Date:   Wed Nov 7 16:35:00 2012 -0500

    USB: report submission of active URBs
    
    This patch (as1633) changes slightly the way usbcore handled
    submissions of URBs that are already active.  It will now return
    -EBUSY rather than -EINVAL, and it will call WARN_ONCE to draw
    people's attention to the bug.
    
    Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Documentation/usb/error-codes.txt b/Documentation/usb/error-codes.txt
index 8d1e2a9..9c3eb84 100644
--- a/Documentation/usb/error-codes.txt
+++ b/Documentation/usb/error-codes.txt
@@ -21,6 +21,8 @@ Non-USB-specific:

 USB-specific:

+-EBUSY		The URB is already active.
+
 -ENODEV		specified USB-device or bus doesn't exist

 -ENOENT		specified interface or endpoint does not exist or
diff --git a/drivers/usb/core/urb.c b/drivers/usb/core/urb.c
index 3662287..e0d9d94 100644
--- a/drivers/usb/core/urb.c
+++ b/drivers/usb/core/urb.c
@@ -321,8 +321,13 @@ int usb_submit_urb(struct urb *urb, gfp_t mem_flags)
 	struct usb_host_endpoint	*ep;
 	int				is_out;

-	if (!urb || urb->hcpriv || !urb->complete)
+	if (!urb || !urb->complete)
 		return -EINVAL;
+	if (urb->hcpriv) {
+		WARN_ONCE(1, "URB %p submitted while active\n", urb);
+		return -EBUSY;
+	}
+
 	dev = urb->dev;
 	if ((!dev) || (dev->state < USB_STATE_UNAUTHENTICATED))
 		return -ENODEV;