The usb_ep_queue() in printer_write() is possible to call req->complete(). In that case, since tx_complete() calls list_add(&req->list, &dev->tx_reqs), printer_write() should not call list_add(&req->list, &dev->tx_reqs_active) because the transfer has already finished. So, this patch checks the condition of req->list before adding the list in printer_write().
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda...@renesas.com> --- This issue can be caused by renesas_usbhs udc driver. I'm not sure this patch is acceptable or not. So, I marked RFC on this patch. drivers/usb/gadget/function/f_printer.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/usb/gadget/function/f_printer.c b/drivers/usb/gadget/function/f_printer.c index d359efe..01de45e 100644 --- a/drivers/usb/gadget/function/f_printer.c +++ b/drivers/usb/gadget/function/f_printer.c @@ -640,10 +640,14 @@ static void tx_complete(struct usb_ep *ep, struct usb_request *req) spin_unlock_irqrestore(&dev->lock, flags); mutex_unlock(&dev->lock_printer_io); return -EAGAIN; + } else if (list_empty(&req->list)) { + /* + * Since usb_ep_queue() is possible to call complete, + * we should check the req->list here, and then add + * it into dev->tx_reqs_active. + */ + list_add(&req->list, &dev->tx_reqs_active); } - - list_add(&req->list, &dev->tx_reqs_active); - } spin_unlock_irqrestore(&dev->lock, flags); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html