From 19162fd4063a3211843b997a454b505edb81d5ce Mon Sep 17 00:00:00 2001 From: Dexuan Cui Date: Mon, 7 Sep 2020 00:13:39 -0700 Subject: hv_netvsc: Fix hibernation for mlx5 VF driver mlx5_suspend()/resume() keep the network interface, so during hibernation netvsc_unregister_vf() and netvsc_register_vf() are not called, and hence netvsc_resume() should call netvsc_vf_changed() to switch the data path back to the VF after hibernation. Note: after we close and re-open the vmbus channel of the netvsc NIC in netvsc_suspend() and netvsc_resume(), the data path is implicitly switched to the netvsc NIC. Similarly, netvsc_suspend() should not call netvsc_unregister_vf(), otherwise the VF can no longer be used after hibernation. For mlx4, since the VF network interafce is explicitly destroyed and re-created during hibernation (see mlx4_suspend()/resume()), hv_netvsc already explicitly switches the data path from and to the VF automatically via netvsc_register_vf() and netvsc_unregister_vf(), so mlx4 doesn't need this fix. Note: mlx4 can still work with the fix because in netvsc_suspend()/resume() ndev_ctx->vf_netdev is NULL for mlx4. Fixes: 0efeea5fb153 ("hv_netvsc: Add the support of hibernation") Signed-off-by: Dexuan Cui Signed-off-by: Jakub Kicinski --- drivers/net/hyperv/netvsc_drv.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) (limited to 'drivers/net/hyperv/netvsc_drv.c') diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c index 64b0a74c1523..81c5c70b616a 100644 --- a/drivers/net/hyperv/netvsc_drv.c +++ b/drivers/net/hyperv/netvsc_drv.c @@ -2587,8 +2587,8 @@ static int netvsc_remove(struct hv_device *dev) static int netvsc_suspend(struct hv_device *dev) { struct net_device_context *ndev_ctx; - struct net_device *vf_netdev, *net; struct netvsc_device *nvdev; + struct net_device *net; int ret; net = hv_get_drvdata(dev); @@ -2604,10 +2604,6 @@ static int netvsc_suspend(struct hv_device *dev) goto out; } - vf_netdev = rtnl_dereference(ndev_ctx->vf_netdev); - if (vf_netdev) - netvsc_unregister_vf(vf_netdev); - /* Save the current config info */ ndev_ctx->saved_netvsc_dev_info = netvsc_devinfo_get(nvdev); @@ -2623,6 +2619,7 @@ static int netvsc_resume(struct hv_device *dev) struct net_device *net = hv_get_drvdata(dev); struct net_device_context *net_device_ctx; struct netvsc_device_info *device_info; + struct net_device *vf_netdev; int ret; rtnl_lock(); @@ -2635,6 +2632,15 @@ static int netvsc_resume(struct hv_device *dev) netvsc_devinfo_put(device_info); net_device_ctx->saved_netvsc_dev_info = NULL; + /* A NIC driver (e.g. mlx5) may keep the VF network interface across + * hibernation, but here the data path is implicitly switched to the + * netvsc NIC since the vmbus channel is closed and re-opened, so + * netvsc_vf_changed() must be used to switch the data path to the VF. + */ + vf_netdev = rtnl_dereference(net_device_ctx->vf_netdev); + if (vf_netdev && netvsc_vf_changed(vf_netdev) != NOTIFY_OK) + ret = -EINVAL; + rtnl_unlock(); return ret; -- cgit v1.2.3