RE: XDP question - how much can BPF change in xdp_buff?

BTW, are we considering some offload where the eBPF would return  a set of
changes [based on some pre-set capabilities set by driver] done on buffer and let
the HW offload those?

I understand end goal is eBPF hw-offloading, but seems like there are a lot of
existing offload facilities that might be leveraged.

On second thought, given that the program is likely to change only a
small set of fields [as opposed to building whole new buffers],
probably fixing the csum isn't going to be much costlier [if at all] then the logic
that would be required to determine whether the device would be able to offload
it.