Re: [PATCH net v3] bonding: Correctly support GSO ESP offload

[Jay Vosburgh <jv@jvosburgh.net>]

Cosmin Ratiu <cratiu@nvidia.com> wrote:

>The referenced fix is incomplete. It correctly computes
>bond_dev->gso_partial_features across slaves, but unfortunately
>netdev_fix_features discards gso_partial_features from the feature set
>if NETIF_F_GSO_PARTIAL isn't set in bond_dev->features.
>
>This is visible with ethtool -k bond0 | grep esp:
>tx-esp-segmentation: off [requested on]
>esp-hw-offload: on
>esp-tx-csum-hw-offload: on
>
>This patch reworks the bonding GSO offload support by:
>- making aggregating gso_partial_features across slaves similar to the
>  other feature sets (this part is a no-op).
>- advertising the default partial gso features on empty bond devs, same
>  as with other feature sets (also a no-op).
>- adding NETIF_F_GSO_PARTIAL to hw_enc_features filtered across slaves.
>- adding NETIF_F_GSO_PARTIAL to features in bond_setup()
>
>With all of these, 'ethtool -k bond0 | grep esp' now reports:
>tx-esp-segmentation: on
>esp-hw-offload: on
>esp-tx-csum-hw-offload: on
>
>Fixes: 4861333b4217 ("bonding: add ESP offload features when slaves support")
>Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
>Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>

Acked-by: Jay Vosburgh <jv@jvosburgh.net>


>---
> drivers/net/bonding/bond_main.c | 19 ++++++++++---------
> 1 file changed, 10 insertions(+), 9 deletions(-)
>
>diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
>index 7b78c2bada81..e45bba240cbc 100644
>--- a/drivers/net/bonding/bond_main.c
>+++ b/drivers/net/bonding/bond_main.c
>@@ -1538,17 +1538,20 @@ static netdev_features_t bond_fix_features(struct net_device *dev,
> 				 NETIF_F_HIGHDMA | NETIF_F_LRO)
> 
> #define BOND_ENC_FEATURES	(NETIF_F_HW_CSUM | NETIF_F_SG | \
>-				 NETIF_F_RXCSUM | NETIF_F_GSO_SOFTWARE)
>+				 NETIF_F_RXCSUM | NETIF_F_GSO_SOFTWARE | \
>+				 NETIF_F_GSO_PARTIAL)
> 
> #define BOND_MPLS_FEATURES	(NETIF_F_HW_CSUM | NETIF_F_SG | \
> 				 NETIF_F_GSO_SOFTWARE)
> 
>+#define BOND_GSO_PARTIAL_FEATURES (NETIF_F_GSO_ESP)
>+
> 
> static void bond_compute_features(struct bonding *bond)
> {
>+	netdev_features_t gso_partial_features = BOND_GSO_PARTIAL_FEATURES;
> 	unsigned int dst_release_flag = IFF_XMIT_DST_RELEASE |
> 					IFF_XMIT_DST_RELEASE_PERM;
>-	netdev_features_t gso_partial_features = NETIF_F_GSO_ESP;
> 	netdev_features_t vlan_features = BOND_VLAN_FEATURES;
> 	netdev_features_t enc_features  = BOND_ENC_FEATURES;
> #ifdef CONFIG_XFRM_OFFLOAD
>@@ -1582,8 +1585,9 @@ static void bond_compute_features(struct bonding *bond)
> 							  BOND_XFRM_FEATURES);
> #endif /* CONFIG_XFRM_OFFLOAD */
> 
>-		if (slave->dev->hw_enc_features & NETIF_F_GSO_PARTIAL)
>-			gso_partial_features &= slave->dev->gso_partial_features;
>+		gso_partial_features = netdev_increment_features(gso_partial_features,
>+								 slave->dev->gso_partial_features,
>+								 BOND_GSO_PARTIAL_FEATURES);
> 
> 		mpls_features = netdev_increment_features(mpls_features,
> 							  slave->dev->mpls_features,
>@@ -1598,12 +1602,8 @@ static void bond_compute_features(struct bonding *bond)
> 	}
> 	bond_dev->hard_header_len = max_hard_header_len;
> 
>-	if (gso_partial_features & NETIF_F_GSO_ESP)
>-		bond_dev->gso_partial_features |= NETIF_F_GSO_ESP;
>-	else
>-		bond_dev->gso_partial_features &= ~NETIF_F_GSO_ESP;
>-
> done:
>+	bond_dev->gso_partial_features = gso_partial_features;
> 	bond_dev->vlan_features = vlan_features;
> 	bond_dev->hw_enc_features = enc_features | NETIF_F_GSO_ENCAP_ALL |
> 				    NETIF_F_HW_VLAN_CTAG_TX |
>@@ -6046,6 +6046,7 @@ void bond_setup(struct net_device *bond_dev)
> 	bond_dev->hw_features |= NETIF_F_GSO_ENCAP_ALL;
> 	bond_dev->features |= bond_dev->hw_features;
> 	bond_dev->features |= NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX;
>+	bond_dev->features |= NETIF_F_GSO_PARTIAL;
> #ifdef CONFIG_XFRM_OFFLOAD
> 	bond_dev->hw_features |= BOND_XFRM_FEATURES;
> 	/* Only enable XFRM features if this is an active-backup config */
>-- 
>2.45.0
>