This is a note to let you know that I've just added the patch titled usb: core: unlink urbs from the tail of the endpoint's urb_list to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: usb-core-unlink-urbs-from-the-tail-of-the-endpoint-s-urb_list.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 2eac13624364db5b5e1666ae0bb3a4d36bc56b6e Mon Sep 17 00:00:00 2001 From: Bin Liu <b-liu@xxxxxx> Date: Tue, 25 Jul 2017 09:31:33 -0500 Subject: usb: core: unlink urbs from the tail of the endpoint's urb_list From: Bin Liu <b-liu@xxxxxx> commit 2eac13624364db5b5e1666ae0bb3a4d36bc56b6e upstream. While unlink an urb, if the urb has been programmed in the controller, the controller driver might do some hw related actions to tear down the urb. Currently usb_hcd_flush_endpoint() passes each urb from the head of the endpoint's urb_list to the controller driver, which could make the controller driver think each urb has been programmed and take the unnecessary actions for each urb. This patch changes the behavior in usb_hcd_flush_endpoint() to pass the urbs from the tail of the list, to avoid any unnecessary actions in an controller driver. Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Bin Liu <b-liu@xxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/core/hcd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -1851,7 +1851,7 @@ void usb_hcd_flush_endpoint(struct usb_d /* No more submits can occur */ spin_lock_irq(&hcd_urb_list_lock); rescan: - list_for_each_entry (urb, &ep->urb_list, urb_list) { + list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) { int is_in; if (urb->unlinked) Patches currently in stable-queue which might be from b-liu@xxxxxx are queue-4.4/usb-core-unlink-urbs-from-the-tail-of-the-endpoint-s-urb_list.patch queue-4.4/usb-musb-fix-tx-fifo-flush-handling-again.patch