4.9-stable review patch. If anyone has any objections, please let me know.
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From: Andrey Vagin avagin@openvz.org
[ Upstream commit 88997e4208aea117627898e5f6f9801cf3cd42d2 ]
wanted_features is a set of features which have to be enabled if a hardware allows that.
Currently when a vlan device is created, its wanted_features is set to current features of its base device.
The problem is that the base device can get new features and they are not propagated to vlan-s of this device.
If we look at bonding devices, they doesn't have this problem and this patch suggests to fix this issue by the same way how it works for bonding devices.
We meet this problem, when we try to create a vlan device over a bonding device. When a system are booting, real devices require time to be initialized, so bonding devices created without slaves, then vlan devices are created and only then ethernet devices are added to the bonding device. As a result we have vlan devices with disabled scatter-gather.
* create a bonding device $ ip link add bond0 type bond $ ethtool -k bond0 | grep scatter scatter-gather: off tx-scatter-gather: off [requested on] tx-scatter-gather-fraglist: off [requested on]
* create a vlan device $ ip link add link bond0 name bond0.10 type vlan id 10 $ ethtool -k bond0.10 | grep scatter scatter-gather: off tx-scatter-gather: off tx-scatter-gather-fraglist: off
* Add a slave device to bond0 $ ip link set dev eth0 master bond0
And now we can see that the bond0 device has got the scatter-gather feature, but the bond0.10 hasn't got it. [root@laptop linux-task-diag]# ethtool -k bond0 | grep scatter scatter-gather: on tx-scatter-gather: on tx-scatter-gather-fraglist: on [root@laptop linux-task-diag]# ethtool -k bond0.10 | grep scatter scatter-gather: off tx-scatter-gather: off tx-scatter-gather-fraglist: off
With this patch the vlan device will get all new features from the bonding device.
Here is a call trace how features which are set in this patch reach dev->wanted_features.
register_netdevice vlan_dev_init ... dev->hw_features = NETIF_F_HW_CSUM | NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_GSO_SOFTWARE | NETIF_F_HIGHDMA | NETIF_F_SCTP_CRC | NETIF_F_ALL_FCOE;
dev->features |= dev->hw_features; ... dev->wanted_features = dev->features & dev->hw_features; __netdev_update_features(dev); vlan_dev_fix_features ...
Cc: Alexey Kuznetsov kuznet@virtuozzo.com Cc: Patrick McHardy kaber@trash.net Cc: "David S. Miller" davem@davemloft.net Signed-off-by: Andrei Vagin avagin@openvz.org Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/8021q/vlan_dev.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
--- a/net/8021q/vlan_dev.c +++ b/net/8021q/vlan_dev.c @@ -562,8 +562,7 @@ static int vlan_dev_init(struct net_devi NETIF_F_HIGHDMA | NETIF_F_SCTP_CRC | NETIF_F_ALL_FCOE;
- dev->features |= real_dev->vlan_features | NETIF_F_LLTX | - NETIF_F_GSO_SOFTWARE; + dev->features |= dev->hw_features | NETIF_F_LLTX; dev->gso_max_size = real_dev->gso_max_size; dev->gso_max_segs = real_dev->gso_max_segs; if (dev->features & NETIF_F_VLAN_FEATURES)