freebsd stable - Jun 2020 - `efivar -l` fails on UEFI booted 11.4-RELEASE

On UEFI booted 11.4-RELEASE system `efivar -l` fails as following.

root at rolling-vm-freebsd3[160]# uname -a
FreeBSD rolling-vm-freebsd3.home.utahime.org 11.4-RELEASE FreeBSD 11.4-RELEASE
#0 r362094: Fri Jun 12 18:27:15 UTC 2020     root at
releng2.nyi.freebsd.org:/usr/obj/usr/src/sys/GENERIC  amd64
root at rolling-vm-freebsd3[161]# efivar -l
efivar: Error listing names: No such file or directory
root at rolling-vm-freebsd3[162]#

It also happens with latest (20200625) 11-STABLE snapshot, but not
with either 12.1-RELEASE or 13-CURRENT.

---
Yasuhiro KIMURA

On Sat, Jun 27, 2020 at 8:04 PM Yasuhiro KIMURA <yasu at utahime.org>
wrote:
>
> On UEFI booted 11.4-RELEASE system `efivar -l` fails as following.
>
> root at rolling-vm-freebsd3[160]# uname -a
> FreeBSD rolling-vm-freebsd3.home.utahime.org 11.4-RELEASE FreeBSD
11.4-RELEASE #0 r362094: Fri Jun 12 18:27:15 UTC 2020     root at
releng2.nyi.freebsd.org:/usr/obj/usr/src/sys/GENERIC  amd64
> root at rolling-vm-freebsd3[161]# efivar -l
> efivar: Error listing names: No such file or directory
> root at rolling-vm-freebsd3[162]#
>
> It also happens with latest (20200625) 11-STABLE snapshot, but not
> with either 12.1-RELEASE or 13-CURRENT.
>
Hi,

This should be an easy fix. :-) EFI Runtime Services on FreeBSD
("EFIRT") wasn't necessarily globally stable until right around
12.0.
For 11.x, you'll need to `kldload efirt` or add `options EFIRT` to
your kernel config before efivar/efibootmgr become usable.

Thanks,

Kyle Evans