Re: [Xen-devel] [PATCH] xen-netfront: drop skb when skb->len > 65535

[Nick Pegg <npegg@xxxxxxxxxx>]

On 3/2/13 8:32 AM, Wei Liu wrote:
> 
> As Nick (npegg@xxxxxxxxxx) pointed out in his email, he saw size 65538.
> I can reproduce this as well by setting vif's mtu to 100 then run iperf.
> 100 was just a random number I came up with when I played with
> fragmentation.
> 

Wei: How exactly did you set the MTU on the vif and what were your
arguments to iperf? I tried this on a test host and was unable to
trigger the XSA-39 protection.

As for a more graceful punishment, I noticed that xenvif_carrier_off()
uses netif_carrier_off() to discard queued packets. Would doing a
netif_carrier_off() and then a netif_carrier_on() be sufficient to drop
the bad packets and keep netback from spinning? Would blinking the vif's
carrier in this way allow the DomU to gracefully resume network traffic?


-Nick

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel