Re: [PATCH v3 1/4] net: Add support for hardware-offloaded encapsulation

[David Miller <davem@davemloft.net>]

From: Joseph Gasparakis <joseph.gasparakis@intel.com>
Date: Fri, 7 Dec 2012 10:24:17 -0800 (PST)

> So the idea here is that the driver will use the headers for checksumming 
> if the skb->encapsulation bit is on. The bit should be set in the protocol 
> driver.
> 
> To answer the second comment, the flags that we use in this series of 
> patches is NETIF_F_IP_CSUM, NETIF_F_IPV6_CSUM and NETIF_F_SG. These are 
> the bits that we propose will be used for checksumming of encapsulation. 
> As per a previous comment in v2, the hw_enc_features field should be used 
> also in the future when NICs have more encap offloads, so one could
> indicate these features there from the driver.
> 
> Furthermore, I submitted a patch for Rx checksumming, where NETIF_F_RXCSUM 
> is used, again in conjunction with skb->encapsulation flag. As I mention 
> in my logs, the driver is expected to set the ip_summed to UNNECESSARY and 
> turn the skb->encapsulation on, to indicate that the inner headers are 
> already HW checksummed.
> 

This is the kind of language that belongs in the commit message and
code comments.