Linux Ethernet Bridging - Dec 2014 - [Bridge] [PATCH net-next] bridge: Add ability to always enable TSO/UFO

From: Toshiaki Makita <makita.toshiaki at lab.ntt.co.jp>
Date: Wed, 10 Dec 2014 11:43:14 +0900
> -	features &= ~NETIF_F_ONE_FOR_ALL;
> +	features &= ~NETIF_F_ONE_FOR_ALL | NETIF_F_GSO_SOFTWARE;
I don't think this is the expression you intend to use.

I think you meant:

	features &= ~(NETIF_F_ONE_FOR_ALL | NETIF_F_GSO_SOFTWARE);

Or:

	features = ~NETIF_F_ONE_FOR_ALL;
	features |= NETIF_F_GSO_SOFTWARE;

On 2014/12/11 4:50, David Miller wrote:
> From: Toshiaki Makita <makita.toshiaki at lab.ntt.co.jp>
> Date: Wed, 10 Dec 2014 11:43:14 +0900
> 
>> -	features &= ~NETIF_F_ONE_FOR_ALL;
>> +	features &= ~NETIF_F_ONE_FOR_ALL | NETIF_F_GSO_SOFTWARE;
> 
> I don't think this is the expression you intend to use.
Thank you, but this is really my intended expression.

"features &= ~NETIF_F_ONE_FOR_ALL" drops all of ONE_FOR_ALL bits
including GSO_SOFTWARE.
But I want to leave GSO_SOFTWARE bits here.
> 
> I think you meant:
> 
> 	features &= ~(NETIF_F_ONE_FOR_ALL | NETIF_F_GSO_SOFTWARE);
ONE_FOR_ALL already includes GSO_SOFTWARE.
> 
> Or:
> 
> 	features = ~NETIF_F_ONE_FOR_ALL;
> 	features |= NETIF_F_GSO_SOFTWARE;
This way, users cannot drop TSO/UFO by ethtool.

Thanks,
Toshiaki Makita