Random boot failures with multiple CPUs in VirtualBox

[Roland Illig <roland.illig%gmx.de@localhost>]

Hi,

I installed
https://nycdn.netbsd.org/pub/NetBSD-daily/HEAD/202204091610Z/amd64/installation/cdrom/boot.iso
on a freshly set up VM with the default settings, using VirtualBox
6.1.32 on Windows 11.

The installation went smooth, and NetBSD booted quickly when the VM had
only 1 CPU configured.

I shut down the VM, increased the CPUs to 4 and started the VM. Booting
did not succeed, the last message is:

[1.0369161] apcicpu3 at cpu3: ACPI CPU

After that, the VM burns CPU cycles but does not proceed.

After I stopped the VM forcefully and restarted it, booting continued to
this message:

[14.5656984] kern.module.path=/stand/amd64/9.99.96/modules
[77.6403715] WARNING: system needs entropy for security; see entropy(7)

The long delay between these messages looks unhealthy. At this point,
ACPI shutdown worked though.

On the next try, booting succeeded in almost no time. After "shutdown -r
now", the next boot hangs after this message:

[1.0080102] acpicpu3 at cpu3: ACPI CPU

After configuring the VM to have 2 CPUs, booting succeeded quickly 5
times in a row.

After configuring the VM to have 3 CPUs, booting stopped after "acpicpu2
at cpu2: ACPI CPU".

Are these known problems?

Roland