On 10/29/2015 10:36 AM, Peter Chen wrote:
Hi, It is due to try to allocate memory with GFP_KERNEL at ISR, below change can fix it, if not better solution, I can submit a patch. diff --git a/drivers/usb/gadget/function/f_loopback.c b/drivers/usb/gadget/function/f_loopback.c index 6b2102b..d2524a1 100644 --- a/drivers/usb/gadget/function/f_loopback.c +++ b/drivers/usb/gadget/function/f_loopback.c @@ -329,7 +329,7 @@ static int alloc_requests(struct usb_composite_dev *cdev, for (i = 0; i < loop->qlen && result == 0; i++) { result = -ENOMEM; - in_req = usb_ep_alloc_request(loop->in_ep, GFP_KERNEL); + in_req = usb_ep_alloc_request(loop->in_ep, GFP_ATOMIC); if (!in_req)
Well... I didn't get this error on my hardware (odroid u3+) and my "other hardware" (dummy_hcd) but agree. This function is called from set_alt() and this may be called in interrupt ctx so this should use GFP_ATOMIC as you suggested.
Best regards, -- Krzysztof Opasiak Samsung R&D Institute Poland Samsung Electronics -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html