mdnsd stops refreshing after a while [openbsd "tl" interface with autoconfprivacy enabled]

[nbriggs]

I can't tell yet whether this is an issue with mdnsd or with the OpenBSD "tl" ethernet driver, but after a number of IPv6 address changes (autoconf privacy enabled) mdnsd stops responding and does not appear to have refreshed for an extended period. If it is shut down it logs an error on attempting to write the "goodbye" messages:

Oct 31 12:20:21 pigeon mdnsd: cache_process: refresh Macadamia.local (AAAA)
Oct 31 12:26:32 pigeon mdnsd: cache_process: refresh silversword._device-info._tcp.local (TXT)
[... no mdnsd refresh entries, a few more errors from the shutdown omitted here ...]
Nov 1 09:30:25 pigeon mdnsd: rr_send_an error 85.42.168.192.in-addr.arpa (PTR)
Nov 1 09:30:25 pigeon mdnsd: rr_send_an error pigeon.local (HINFO)
Nov 1 09:30:25 pigeon mdnsd: terminating

turning off the IPv6 address refresh seems to stop the problem.

I'll continue to investigate.