From 042b2046d0f05cf8124c26ff65dbb6148a4404fb Mon Sep 17 00:00:00 2001 From: Dongli Zhang Date: Fri, 22 Oct 2021 16:31:39 -0700 Subject: [PATCH] xen/netfront: stop tx queues during live migration The tx queues are not stopped during the live migration. As a result, the ndo_start_xmit() may access netfront_info->queues which is freed by talk_to_netback()->xennet_destroy_queues(). This patch is to netif_device_detach() at the beginning of xen-netfront resuming, and netif_device_attach() at the end of resuming. CPU A CPU B talk_to_netback() -> if (info->queues) xennet_destroy_queues(info); to free netfront_info->queues xennet_start_xmit() to access netfront_info->queues -> err = xennet_create_queues(info, &num_queues); The idea is borrowed from virtio-net. Cc: Joe Jin Signed-off-by: Dongli Zhang Signed-off-by: David S. Miller --- drivers/net/xen-netfront.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index e31b98403f31..fc41ba95f81d 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -1730,6 +1730,10 @@ static int netfront_resume(struct xenbus_device *dev) dev_dbg(&dev->dev, "%s\n", dev->nodename); + netif_tx_lock_bh(info->netdev); + netif_device_detach(info->netdev); + netif_tx_unlock_bh(info->netdev); + xennet_disconnect_backend(info); return 0; } @@ -2349,6 +2353,10 @@ static int xennet_connect(struct net_device *dev) * domain a kick because we've probably just requeued some * packets. */ + netif_tx_lock_bh(np->netdev); + netif_device_attach(np->netdev); + netif_tx_unlock_bh(np->netdev); + netif_carrier_on(np->netdev); for (j = 0; j < num_queues; ++j) { queue = &np->queues[j]; -- 2.39.5