Re: [net-next,v2,1/4] net: use ndo_set_features to set offload features for bonding/bridge/team
From: Simon Horman <horms@kernel.org>
Date: 2026-03-15 16:20:05
Also in:
bridge, lkml
This is an AI-generated review of your patch. The human sending this email has considered the AI review valid, or at least plausible. For local reproduction steps see https://netdev-ai.bots.linux.dev/ai-local.html --- net: use ndo_set_features to set offload features for bonding/bridge/team This commit converts bonding, bridge, and team drivers to use the ndo_set_features callback instead of manually calling netdev_compute_master_upper_features() during port add/remove operations.
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diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index 90b71bd53040..2c84d3ce3b04 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c
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@@ -5953,6 +5957,7 @@ static const struct net_device_ops bond_netdev_ops = { .ndo_add_slave = bond_enslave, .ndo_del_slave = bond_release, .ndo_fix_features = bond_fix_features, + .ndo_set_features = bond_set_features, .ndo_features_check = passthru_features_check, .ndo_get_xmit_slave = bond_xmit_get_slave, .ndo_sk_get_lower_dev = bond_sk_get_lower_dev,
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diff --git a/drivers/net/team/team_core.c b/drivers/net/team/team_core.c index b7282f5c9632..4906ea3717b1 100644 --- a/drivers/net/team/team_core.c +++ b/drivers/net/team/team_core.c
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@@ -2007,6 +2010,7 @@ static const struct net_device_ops team_netdev_ops = { .ndo_add_slave = team_add_slave, .ndo_del_slave = team_del_slave, .ndo_fix_features = team_fix_features, + .ndo_set_features = team_set_features, .ndo_change_carrier = team_change_carrier, .ndo_features_check = passthru_features_check, };
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diff --git a/net/bridge/br_device.c b/net/bridge/br_device.c index f7502e62dd35..f82082050e36 100644 --- a/net/bridge/br_device.c +++ b/net/bridge/br_device.c
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@@ -456,6 +462,7 @@ static const struct net_device_ops br_netdev_ops = { .ndo_add_slave = br_add_slave, .ndo_del_slave = br_del_slave, .ndo_fix_features = br_fix_features, + .ndo_set_features = br_set_features, .ndo_fdb_add = br_fdb_add, .ndo_fdb_del = br_fdb_delete, .ndo_fdb_del_bulk = br_fdb_delete_bulk,
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diff --git a/net/core/dev.c b/net/core/dev.c index f48dc299e4b2..16b3fc620807 100644 --- a/net/core/dev.c +++ b/net/core/dev.c@@ -8920,6 +8920,9 @@ static int __netdev_upper_dev_link(struct net_device *dev, __netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level, priv); + /* re-compute all features after adding link */ + netdev_change_features(upper_dev); + return 0; rollback:
Can the feature computation skip updating ancillary fields when features
don't change?
The new architecture routes computation through netdev_change_features() ->
__netdev_update_features() -> ndo_set_features(). However,
__netdev_update_features() has this check:
net/core/dev.c:__netdev_update_features() {
...
if (dev->features == features)
goto sync_lower;
This skips the ndo_set_features callback entirely when computed features
match current features. This means netdev_compute_master_upper_features() is
never called when dev->features doesn't change, even though it updates
several ancillary fields independent of dev->features:
- vlan_features
- hw_enc_features
- mpls_features
- gso_partial_features
- tso_max_size
- tso_max_segs
- hard_header_len
- needed_headroom
- needed_tailroom
For example, adding a second bond slave with identical dev->features but
different tso_max_size or vlan_features will not trigger ndo_set_features,
leaving the bond's ancillary fields stale.
In the old code, netdev_compute_master_upper_features() was called
unconditionally and always updated these fields regardless of whether
dev->features changed.
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@@ -9012,6 +9015,9 @@ static void __netdev_upper_dev_unlink(struct net_device *dev, __netdev_update_lower_level(upper_dev, priv); __netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level, priv); + + /* re-compute all features after removing link */ + netdev_change_features(upper_dev); }
The same issue applies here. When a port is removed but dev->features doesn't change, the ancillary fields won't be recomputed.
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@@ -12874,8 +12880,6 @@ void netdev_compute_master_upper_features(struct net_device *dev, bool update_he netif_set_tso_max_segs(dev, tso_max_segs); netif_set_tso_max_size(dev, tso_max_size); - - netdev_change_features(dev); } EXPORT_SYMBOL(netdev_compute_master_upper_features);