problem with bhyve, ryzen 5800x, freebsd guest

From: Andriy Gapon <>
Date: Thu, 07 Jul 2022 12:29:04 UTC
I have a strange issue with running an 'appliance' image based on 
FreeBSD 12 in bhyve on a machine with Ryzen 5800x processor.

The problem is that the guest would run for a while and then the host 
would suddenly reset itself.  It appears like a triple fault or 
something with similar consequences.

The time may be from a few dozens of minutes to many hours.

Just to be clear, no such thing occurs if I do not run the guest.
Also, I have an older AMD system (pre-Zen), the problem does not happen 
A vanilla FreeBSD 12.3 installation that just sits idle also does not 
cause the problem.

Does anyone have an idea what the problem could be?
What workaround or diagnostics to try?
Anybody else seen something like this?

Since it's the host that resets it would be hard to capture any traces.
Thank you.
Andriy Gapon