From: Dongli Zhang dongli.zhang@oracle.com
[ Upstream commit 042b2046d0f05cf8124c26ff65dbb6148a4404fb ]
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 joe.jin@oracle.com Signed-off-by: Dongli Zhang dongli.zhang@oracle.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- 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 88280057e0321..7d389c2cc9026 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -1439,6 +1439,10 @@ 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; } @@ -1987,6 +1991,10 @@ 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];