FreeBSD 12.1 i386 on Hyper-V Fails to Mount Root

[Chris Knight]

Howdy,

Just started the upgrade process on some FreeBSD 11.4 VMs to FreeBSD 12.1
using freebsd-update. VMs are running on multiple Hyper-V 2012 R2 and 2019
systems, all systems with 2020-09 Cumulative Updates installed.
The amd64 VMs are upgrading happily.
The i386 VMs die a horrible death - the kernel throws the following error:

vmbus0: cannot find free IDT vector

shortly followed by mountroot failure due to the lack of storage device
initialisation.
Checked the FreeBSD 12.1 i386 ISO in case of environment pollution - same
vmbus error, same lack of storage device initialisation failure. Ditto with
the 12.2-RC2 i386 ISO.

Any loader.conf tricks I can try to get these to boot, or simply time to
accept that i386 is now that poor orphan that nobody wants to acknowledge,
bite the bullet and migrate these to amd64 (if I can - rotten legacy
software)?




-- 
Regards,
Chris Knight