It's possibly a bug. Based on your description, it is more likely a hardware problem. The delay occurs between the probe of your second pciide bus (pciide1) and finding the hard drive (wd0) on that bus.
Question: Was this delay present when you booted the GENERIC kernel, or does it appear only when use use the GENERIC.MP kernel?
Question: Did this delay happen with the RAMDISK (/bsd.rd) kernel, too?
If it always happens, then it is most likely indicative of some problem communicating with the hard drive's electronics.
It is possible that you might obtain additional information on your console (and dmesg) during the hardware probes by booting in verbose mode. To do that:
At the boot> prompt, use the -c option. e.g.:boot> boot bsd.mp -c
Then, at the UKC> prompt, set verbose mode:UKC> verbose
UKC> quit
For more information, see
boot(8) and
boot_config(8).