Subject: Re: expected behavior of PF_PACKET on NETIF_F_HW_VLAN_RX device?

From: Ben Greear <[email-masked]>
Date: Wed, 31 Oct 2007 18:31:10 -0700

Stephen Hemminger wrote:
>
> The code in AF_PACKET should fix the skb before passing to user space 
> so that there is
> no difference between accel and non-accel hardware.  Internal choices 
> shouldn't
> leak to user space.  Ditto, the receive checksum offload should be 
> fixed up as well.
Ok, I guess that will fix the sniffing issues and any user-space 
bridging type applications.

Currently, VLAN devices offer the ability to 'reorder' the header and 
explicitly remove the VLAN
header.  I assume we keep this feature and have the AF_PACKET logic 
check the device
flags to see if it should insert the VLAN header for hw-accel vlans?

Either way, if we sniff the underlying device, we should always get the 
VLAN header.

What about drivers and filtering VLANs?  It seems there is still a 
difference between software
vlans and hw-accel in this case.

Thanks,
Ben

-- 
Ben Greear <[email-masked]> 
Candela Technologies Inc  http://www.candelatech.com