Linux Virtualization - May 2021 - [PATCH 4/4] tun: indicate support for USO feature

? 2021/5/11 ??12:42, Yuri Benditovich ??:
> Signed-off-by: Yuri Benditovich <yuri.benditovich at daynix.com>
> ---
>   drivers/net/tun.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/tun.c b/drivers/net/tun.c
> index 84f832806313..a35054f9d941 100644
> --- a/drivers/net/tun.c
> +++ b/drivers/net/tun.c
> @@ -2812,7 +2812,7 @@ static int set_offload(struct tun_struct *tun,
unsigned long arg)
>   			arg &= ~(TUN_F_TSO4|TUN_F_TSO6);
>   		}
>   
> -		arg &= ~TUN_F_UFO;
> +		arg &= ~(TUN_F_UFO|TUN_F_USO);

It looks to me kernel doesn't use "USO", so TUN_F_UDP_GSO_L4 is a
better
name for this and I guess we should toggle NETIF_F_UDP_GSO_l4 here?

And how about macvtap?

Thanks

>   	}
>   
>   	/* This gives the user a way to test for new features in future by

On Tue, May 11, 2021 at 9:50 AM Jason Wang <jasowang at redhat.com>
wrote:
>
>
> ? 2021/5/11 ??12:42, Yuri Benditovich ??:
> > Signed-off-by: Yuri Benditovich <yuri.benditovich at daynix.com>
> > ---
> >   drivers/net/tun.c | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/tun.c b/drivers/net/tun.c
> > index 84f832806313..a35054f9d941 100644
> > --- a/drivers/net/tun.c
> > +++ b/drivers/net/tun.c
> > @@ -2812,7 +2812,7 @@ static int set_offload(struct tun_struct *tun,
unsigned long arg)
> >                       arg &= ~(TUN_F_TSO4|TUN_F_TSO6);
> >               }
> >
> > -             arg &= ~TUN_F_UFO;
> > +             arg &= ~(TUN_F_UFO|TUN_F_USO);
>
>
> It looks to me kernel doesn't use "USO", so TUN_F_UDP_GSO_L4
is a better
> name for this
No problem, I can change it in v2

 and I guess we should toggle NETIF_F_UDP_GSO_l4 here?

No, we do not, because this indicates only the fact that the guest can
send large UDP packets and have them splitted to UDP segments.
>
> And how about macvtap?
We will check how to do that for macvtap. We will send a separate
patch for macvtap or ask for advice.
>
> Thanks
>
>
> >       }
> >
> >       /* This gives the user a way to test for new features in future
by
>