[ovs-dev] [PATCH] datapath: Update hardware computed checksum on VLAN change.

Ben Pfaff blp at nicira.com
Thu Mar 4 23:58:19 UTC 2010


On Thu, Mar 04, 2010 at 04:58:17PM -0500, Jesse Gross wrote:
> The checksum computed by hardware on receive stored in skb->csum
> when skb->ip_summed == CHECKSUM_COMPLETE is supposed to reflect
> the contents of the packet starting at skb->data, which includes
> the VLAN tag if there is one.  However, when we manipulate the
> VLAN tag we don't update the checksum.  This leads to all kinds
> of nasty warnings about broken hardware, not to mention we can't
> take advantage of the checksum that was already computed.

Wow, great catch.

The only comment I have is that I have trouble remember whether the
OVS-private constants are CSUM_* or CHECKSUM_*.  So ideally we'd rename
them to something that begins with OVS_.




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