From: Felipe Balbi Date: Tue, 4 Oct 2016 12:14:43 +0000 (+0300) Subject: usb: gadget: function: u_ether: don't starve tx request queue X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=6c83f77278f17a7679001027e9231291c20f0d8a;p=linux-beck.git usb: gadget: function: u_ether: don't starve tx request queue If we don't guarantee that we will always get an interrupt at least when we're queueing our very last request, we could fall into situation where we queue every request with 'no_interrupt' set. This will cause the link to get stuck. The behavior above has been triggered with g_ether and dwc3. Cc: Reported-by: Ville Syrjälä Signed-off-by: Felipe Balbi --- diff --git a/drivers/usb/gadget/function/u_ether.c b/drivers/usb/gadget/function/u_ether.c index 9c8c9ed1dc9e..fe1811650dbc 100644 --- a/drivers/usb/gadget/function/u_ether.c +++ b/drivers/usb/gadget/function/u_ether.c @@ -590,8 +590,9 @@ static netdev_tx_t eth_start_xmit(struct sk_buff *skb, /* throttle high/super speed IRQ rate back slightly */ if (gadget_is_dualspeed(dev->gadget)) - req->no_interrupt = (dev->gadget->speed == USB_SPEED_HIGH || - dev->gadget->speed == USB_SPEED_SUPER) + req->no_interrupt = (((dev->gadget->speed == USB_SPEED_HIGH || + dev->gadget->speed == USB_SPEED_SUPER)) && + !list_empty(&dev->tx_reqs)) ? ((atomic_read(&dev->tx_qlen) % dev->qmult) != 0) : 0;