Re: [PATCH v4] Send an initial ARP and NDP request to resolve the guest IP

[Stefano Brivio <sbrivio@redhat.com>]

On Wed, 10 Sep 2025 13:35:40 +0200
Volker Diels-Grabsch <v@njh.eu> wrote:

> Changes from PATCH v3:   (... which wasn't marked as "v3", sorry for that)
> 
> 1. Simply remove the "e.g." part from the comment, as it's misleading anyways
> 2. Make "bufmac[]" as local as possible
> 3. Demote the "Sending initial ..." log message from info() to debug()
> 4. Log "Sending initial ..." separately for ARP and NDP (because of 5. and 6.)
> 5. Send initial ARP request only if IPv4 is enabled
> 6. Send initial NDP request only if IPv6, NDP and ICMP are enabled
> 7. Update description of "--no-ndp" in man page
> 8. Fix and update description of "--no-icmp" in man page
> 9. Break long line for MAC_BROADCAST

By the way, same as most kernel subsystems, we commonly write change
revisions after the marker for the end of commit message, say:

  text text text

  Tag: x
  Signed-off-by: y
  ---
  v3:
    - a
    - b
    - c

or whatever variation one might find convenient. But it's nice to have
it there, because it's not polluting the commit message, and at the
same time it comes in the same email as the change.

This is different from Linux kernel net.git / net-next.git submissions,
where there's a general request to include version changes in commit
messages, but I don't think that's a good idea, as sometimes net.git
commit messages get rather long and unreadable because of that.

> One final thought regarding 8.:
> 
> Would it make sense to state in the man page that "--no-icmp" implies
> "--no-ndp", and to implement it rigorously that way?  Or, would that
> be going to far?

I'm not sure if it's going too far, but given that we currently disable
just a bit of NDP on --no-icmp, I'd say it's better to make it
consistent at this point with the strict interpretation you added in v4.

-- 
Stefano