From a9232076374334ca2bc2a448dfde96d38a54349a Mon Sep 17 00:00:00 2001 From: Jeff Westfahl Date: Thu, 29 May 2014 09:49:41 +0300 Subject: [PATCH] usb: gadget: u_ether: synchronize with transmit when stopping queue When disconnecting, it's possible that another thread has already made it into eth_start_xmit before we call netif_stop_queue. This can lead to a crash as eth_start_xmit tries to use resources that gether_disconnect is freeing. Use netif_tx_lock/unlock around netif_stop_queue to ensure no threads are executing during the remainder of gether_disconnect. Signed-off-by: Jeff Westfahl Tested-by: Jaeden Amero Signed-off-by: Felipe Balbi --- drivers/usb/gadget/u_ether.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/usb/gadget/u_ether.c b/drivers/usb/gadget/u_ether.c index 3d78a8844e43..97b027724ee7 100644 --- a/drivers/usb/gadget/u_ether.c +++ b/drivers/usb/gadget/u_ether.c @@ -1120,7 +1120,10 @@ void gether_disconnect(struct gether *link) DBG(dev, "%s\n", __func__); + netif_tx_lock(dev->net); netif_stop_queue(dev->net); + netif_tx_unlock(dev->net); + netif_carrier_off(dev->net); /* disable endpoints, forcing (synchronous) completion -- 2.20.1