From: Eric Dumazet <edumazet@xxxxxxxxxx> [ Upstream commit f8d7408a4d7f60f8b2df0f81decdc882dd9c20dc ] lan78xx_tx_bh() makes sure to not exceed MAX_SINGLE_PACKET_SIZE bytes in the aggregated packets it builds, but does nothing to prevent large GSO packets being submitted. Pierre-Francois reported various hangs when/if TSO is enabled. For localy generated packets, we can use netif_set_gso_max_size() to limit the size of TSO packets. Note that forwarded packets could still hit the issue, so a complete fix might require implementing .ndo_features_check for this driver, forcing a software segmentation if the size of the TSO packet exceeds MAX_SINGLE_PACKET_SIZE. Fixes: 55d7de9de6c3 ("Microchip's LAN7800 family USB 2/3 to 10/100/1000 Ethernet device driver") Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx> Reported-by: RENARD Pierre-Francois <pfrenard@xxxxxxxxx> Tested-by: RENARD Pierre-Francois <pfrenard@xxxxxxxxx> Cc: Stefan Wahren <stefan.wahren@xxxxxxxx> Cc: Woojung Huh <woojung.huh@xxxxxxxxxxxxx> Cc: Microchip Linux Driver Support <UNGLinuxDriver@xxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/usb/lan78xx.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/net/usb/lan78xx.c +++ b/drivers/net/usb/lan78xx.c @@ -2961,6 +2961,7 @@ static int lan78xx_probe(struct usb_inte if (netdev->mtu > (dev->hard_mtu - netdev->hard_header_len)) netdev->mtu = dev->hard_mtu - netdev->hard_header_len; + netif_set_gso_max_size(netdev, MAX_SINGLE_PACKET_SIZE - MAX_HEADER); dev->ep_blkin = (intf->cur_altsetting)->endpoint + 0; dev->ep_blkout = (intf->cur_altsetting)->endpoint + 1;