Microcode update prevents boot

[Leon Dietrich]

Hi there,

I already worked around the issue myself. I'm just writing this here in
case someone else may have the same issue and is seeking an answer.


I recently upgraded the intel cpu microcode update package. Since then
the boot process hang at the stage where the other cpu cores where
enabled (shortly after enabling acpi). In order to resolve the issue one
has to boot in safe mode (not single user mode!) and comment (or remove)
the lines enabling the cpu microcode update on boot in
/boot/loader.conf. One can and should reboot then.

After making these changes the system boots again and all cores are
started and SMT works as well. One should note that one's not running
the newer microcode (including some security-) fixes. Having
microcode_update_enable="YES" in /etc/rc.conf doesn't prevent booting
and does not cause noticeable instability.

For reference: Im running FreeBSD 12.1 on a supermicro embedded board
with intel xeon E3-1585L v5 cpus.


I hope someone will find this info useful.

Leon Dietrich