kern/54143: kernel crashes with amd64 CURRENT iso in virtualbox

[rares.aioanei%gmail.com@localhost]

>Number:         54143
>Category:       kern
>Synopsis:       kernel crashes with amd64 CURRENT iso in virtualbox
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Apr 28 09:35:00 +0000 2019
>Originator:     Rares Aioanei
>Release:        8.99.37 from 27th and 28th of April 2019
>Organization:
>Environment:
--
>Description:
https://pasteboard.co/IccP7JX.png
The underlying hardware is a AMD Ryzen machine, and NetBSD 8.0 works just fine in VBox with the same configuration.
>How-To-Repeat:
Boot a recent CURRENT iso in VirtualBox (amd64) on a AMD Ryzen host.
>Fix: