xhci: Fix oops caused by more USB2 ports than USB3 ports.

commit 3278a55a1aebe2bbd47fbb5196209e5326a88b56 upstream.

The code to set the device removable bits in the USB 2.0 roothub
descriptor was accidentally looking at the USB 3.0 port registers
instead of the USB 2.0 registers.  This can cause an oops if there are
more USB 2.0 registers than USB 3.0 registers.

This should be backported to kernels as old as 2.6.39, that contain the
commit 4bbb0ace9a3de8392527e3c87926309d541d3b00 "xhci: Return a USB 3.0
hub descriptor for USB3 roothub."

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

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index 430e88f..a8b2980 100644 (file)
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -95,7 +95,7 @@ static void xhci_usb2_hub_descriptor(struct usb_hcd *hcd, struct xhci_hcd *xhci,
         */
        memset(port_removable, 0, sizeof(port_removable));
        for (i = 0; i < ports; i++) {
-               portsc = xhci_readl(xhci, xhci->usb3_ports[i]);
+               portsc = xhci_readl(xhci, xhci->usb2_ports[i]);
                /* If a device is removable, PORTSC reports a 0, same as in the
                 * hub descriptor DeviceRemovable bits.
                 */