This is a note to let you know that I've just added the patch titled usb: gadget: udc: core: update usb_ep_queue() documentation to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-next branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will also be merged in the next major kernel release during the merge window. If you have any questions about this process, please let me know. >From eaa358c7790338d83bb6a31258bdc077de120414 Mon Sep 17 00:00:00 2001 From: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx> Date: Mon, 26 Mar 2018 13:14:46 +0300 Subject: usb: gadget: udc: core: update usb_ep_queue() documentation Mention that ->complete() should never be called from within usb_ep_queue(). Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx> Cc: stable <stable@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/gadget/udc/core.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c index 50988b21a21b..842814bc0e4f 100644 --- a/drivers/usb/gadget/udc/core.c +++ b/drivers/usb/gadget/udc/core.c @@ -238,6 +238,9 @@ EXPORT_SYMBOL_GPL(usb_ep_free_request); * arranges to poll once per interval, and the gadget driver usually will * have queued some data to transfer at that time. * + * Note that @req's ->complete() callback must never be called from + * within usb_ep_queue() as that can create deadlock situations. + * * Returns zero, or a negative error code. Endpoints that are not enabled * report errors; errors will also be * reported when the usb peripheral is disconnected. -- 2.16.3