USB: xhci: Don't wait for a disable slot cmd when HC dies.

When the host controller dies or is removed while a device is plugged in,
the USB core will attempt to deallocate the struct usb_device.  That will
call into xhci_free_dev().  This function used to attempt to submit a
disable slot command to the host controller and clean up the device
structures when that command returned.  Change xhci_free_dev() to skip the
command submission and just free the memory if the host controller died.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 9 insertions, 0 deletions

diff --git a/drivers/usb/host/xhci-hcd.c b/drivers/usb/host/xhci-hcd.c
index 592e742c5f35..d61c49f90f4a 100644
--- a/drivers/usb/host/xhci-hcd.c
+++ b/drivers/usb/host/xhci-hcd.c
@@ -1428,11 +1428,20 @@ void xhci_free_dev(struct usb_hcd *hcd, struct usb_device *udev)
 {
         struct xhci_hcd *xhci = hcd_to_xhci(hcd);
         unsigned long flags;
+        u32 state;
 
         if (udev->slot_id == 0)
                 return;
 
         spin_lock_irqsave(&xhci->lock, flags);
+        /* Don't disable the slot if the host controller is dead. */
+        state = xhci_readl(xhci, &xhci->op_regs->status);
+        if (state == 0xffffffff) {
+                xhci_free_virt_device(xhci, udev->slot_id);
+                spin_unlock_irqrestore(&xhci->lock, flags);
+                return;
+        }
+
         if (xhci_queue_slot_control(xhci, TRB_DISABLE_SLOT, udev->slot_id)) {
                 spin_unlock_irqrestore(&xhci->lock, flags);
                 xhci_dbg(xhci, "FIXME: allocate a command ring segment\n");