From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:48573 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S941835AbcJSOpu (ORCPT ); Wed, 19 Oct 2016 10:45:50 -0400 Subject: patch "usb: gadget: function: u_ether: don't starve tx request queue" added to usb-linus To: felipe.balbi@linux.intel.com, stable@vger.kernel.org, ville.syrjala@linux.intel.com From: Date: Wed, 19 Oct 2016 15:27:38 +0200 Message-ID: <147688365813970@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled usb: gadget: function: u_ether: don't starve tx request queue 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-linus 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 hopefully also be merged in Linus's tree for the next -rc kernel release. If you have any questions about this process, please let me know. >>From 6c83f77278f17a7679001027e9231291c20f0d8a Mon Sep 17 00:00:00 2001 From: Felipe Balbi Date: Tue, 4 Oct 2016 15:14:43 +0300 Subject: usb: gadget: function: u_ether: don't starve tx request queue MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 --- drivers/usb/gadget/function/u_ether.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) 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; -- 2.10.0