[ovs-dev] [PATCH 07/19] datapath: Correctly update update IP checksum with actions.

Ben Pfaff blp at nicira.com
Thu Dec 9 17:58:30 UTC 2010


On Wed, Dec 08, 2010 at 10:14:05PM -0800, Jesse Gross wrote:
> The update_csum() function that we currently use to update
> checksums on actions is really intended for L4 checksums.  In
> particular, if the packet has a partial checksum and the field
> is not in the pseudo header, it doesn't do anything at all.
> This doesn't make sense for the IP header because Linux doesn't
> use hardware offload for it, so we always need to recompute the
> checksum.  Instead, we can use the kernel function csum_replace4(),
> which will always do the right thing.
> 
> Signed-off-by: Jesse Gross <jesse at nicira.com>

Acked-by: Ben Pfaff <blp at nicira.com>




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