Re: [PATCH net] Bonding: Fix support for gso_partial_features

[Hangbin Liu <liuhangbin@gmail.com>]

On Tue, Jan 21, 2025 at 08:55:25AM +0000, Hangbin Liu wrote:
> The fixed commit adds NETIF_F_GSO_ESP bit for bonding gso_partial_features.
> However, if we don't set the dev NETIF_F_GSO_PARTIAL bit, the later
> netdev_change_features() -> netdev_fix_features() will remove the
> NETIF_F_GSO_ESP bit from the dev features. This causes ethtool to show
> that the bond does not support tx-esp-segmentation. For example
> 
>  # ethtool -k bond0 | grep esp
>  tx-esp-segmentation: off [requested on]
>  esp-hw-offload: on
>  esp-tx-csum-hw-offload: on
> 
> Add the NETIF_F_GSO_PARTIAL bit to bond dev features when set
> gso_partial_features to fix this issue.
> 
> Fixes: 4861333b4217 ("bonding: add ESP offload features when slaves support")
> Reported-by: Liang Li <liali@redhat.com>
> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
> ---
>  drivers/net/bonding/bond_main.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
> index 7b78c2bada81..e1c054416d5e 100644
> --- a/drivers/net/bonding/bond_main.c
> +++ b/drivers/net/bonding/bond_main.c
> @@ -1598,10 +1598,12 @@ 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)
> +	if (gso_partial_features & NETIF_F_GSO_ESP) {
>  		bond_dev->gso_partial_features |= NETIF_F_GSO_ESP;
> -	else
> +		bond_dev->features |= NETIF_F_GSO_PARTIAL;
> +	} else {
>  		bond_dev->gso_partial_features &= ~NETIF_F_GSO_ESP;
> +	}

Hmm, looks we need to remove NETIF_F_GSO_PARTIAL when remove the
gso_partial_features.

BTW, I saw some drivers set NETIF_F_GSO_PARTIAL on dev->features. Some
other drivers set NETIF_F_GSO_PARTIAL on dev->hw_enc_features. I haven't
see a doc about where we should set. Please tell me if you have any comments.

Thanks
Hangbin