3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> commit 284d20552461466b04d6bfeafeb1c47a8891b591 upstream. When a command times out, the command ring is first aborted, and then stopped. If the command ring is empty when it is stopped the stop event will point to next command which is not yet set. xHCI tries to handle this next event often causing an oops. Don't handle command completion events on stopped cmd ring if ring is empty. This patch should be backported to kernels as old as 3.7, that contain the commit b92cc66c047ff7cf587b318fe377061a353c120f "xHCI: add aborting command ring function" Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> Reported-by: Giovanni <giovanni.nervi@xxxxxxxxx> Signed-off-by: Sarah Sharp <sarah.a.sharp@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/host/xhci-ring.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -1400,6 +1400,12 @@ static void handle_cmd_completion(struct inc_deq(xhci, xhci->cmd_ring); return; } + /* There is no command to handle if we get a stop event when the + * command ring is empty, event->cmd_trb points to the next + * unset command + */ + if (xhci->cmd_ring->dequeue == xhci->cmd_ring->enqueue) + return; } switch (le32_to_cpu(xhci->cmd_ring->dequeue->generic.field[3]) -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html