On Sun, Oct 05, 2025 at 09:39:37AM -0400, Jon Maloy wrote:
> 
> 
> On 2025-10-03 01:33, David Gibson wrote:
> > On Thu, Oct 02, 2025 at 08:34:03PM -0400, Jon Maloy wrote:
> > > 
> > > 
> > > Bug #120 asks us to use the true MAC addresses of LAN local
> > > remote hosts, since some programs need this information.
> > > These commits introduces this for ARP, NDP, UDP, TCP and
> > > ICMP.
> > 
> > I have a bunch of more detailed comments on the patches, but they're a
> > bit confused, because for the earlier ones I hadn't read the whole
> > series to get the whole context.
> > 
> > There is a problem here in that you're not consistent about whether
> > the neighbour table is indexed by host side addresses or guest side
> > addresses.  You'll mostly get away with this, because they're
> > usually the same.  But it will result in bugs on the edge cases.
> > 
> > Having read the whole series now, I think it will be simplest to
> > standardize on indexing by guest side addresses.  That invalidates
> > some of my earlier comments, but instead you'll need to use
> > nat_inbound() when you populate the table from netlink updates.
> > 
> 
> I think I agree. After all this is all about what we are showing the
> guest in the form of IP and MAC addresses, so it is conceptually clearer.
> 
> It doesn't change the implementation much, but it makes it easier
> to understand which special cases we need to consider.

Agreed.  I think it will also make this easier to extend for
guest-side ARP lookups in future, which we'll want for handling
multiple guests.

> See my next email.


-- 
David Gibson (he or they)	| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you, not the other way
				| around.
http://www.ozlabs.org/~dgibson