kvm vlan virtio problem

[Bryan Venteicher]

Hi,

----- Original Message -----
> Hi!
> 
> The same warning shows up in our setup:
> 
> Jan 21 23:40:46 host kernel: WARNING: at net/core/dev.c:1712
> skb_gso_segment+0x1df/0x2b0() (Tainted: G        W  ---------------   )
> Jan 21 23:40:46 host kernel: Hardware name: System Product Name
> Jan 21 23:40:46 host kernel: tun: caps=(0x1b0049, 0x0) len=4452
> data_len=4380 ip_summed=0
> [...]
> 
> KVM host: CentOS 6.3, Linux kernel 2.6.32-279.19.1.el6.x86_64
> VM guest: FreeBSD 9.1, virtio-kmod-9.1-0.242658
> 
> Disabling TSO on vtnet0 stops the warnings on the KVM host.
> 
> Is there any progress on this issue?
> 

It seems the only way this could happen is if the FreeBSD TCP/IP
stack sent down an mbuf with CSUM_TSO set and CSUM_TCP not set;
this doesn't seem possible from looking at FreeBSD's tcp_output().

I'll try to look closer at this during this week.

Bryan


> 	Best regards
> 		Franz
>