Loader can't find /boot/ua/loader.lua on UFS after main-n255828-18054d0220c

-- but only on one machine (of the 3 that I use for daily tracking head
(and stable/12 & stable/13) -- the build machine ("freebeast").

Each is amd64, using ... venerable ... BIOS/MBR & UFS -- stuff that has
generally been functionally stable for the last couple of decades.

So for yesterday and today, I've moved the new loader aside and copied
the one from Friday, which works just fine.

The build machine ("freebeast") uses a GENERIC kernel; the other 2 are
laptops, and use a kernel that includes GENERIC, then tweaks things a
bit (e.g., dropping support for tape drives; adding IPFIREWALL and
explicitly NOT setting IPFIREWALL_DEFAULT_TO_ACCEPT; adding sound stuff).

Info on the update history & copies of stuff like most recent
(verbosely-booted) dmesg.boot should be available at
https://www.catwhisker.org/~david/FreeBSD/history/ (and if you can't get
through, please send a note to dhw@freebsd.org and I'll do what I can to
fix it).

(Of the 2 laptops, I only have the one that I actuaqlly use in
day-to-day work represented.)

(I note that to recover, I boot from one the stable/* slices, move the
"head" slice's files around, then reboot from the "head" slice.)

AFAICT, there were no changes to stand/* since main-n255828-18054d0220c,
though yesterday (main-n255828-18054d0220c -> main-n255840-9cb70cb4769),
there were some changes to sys/ufs/ffs/ffs_subr.c (from
main-n255835-076002f24d35:

commit 076002f24d35962f0d21f44bfddd34ee4d7f015d
Author: Kirk McKusick <mckusick@FreeBSD.org>
Date:   Fri May 27 12:21:11 2022 -0700

    Do comprehensive UFS/FFS superblock integrity checks when reading a superblock.
    
    Historically only minimal checks were made of a superblock when it
    was read in as it was assumed that fsck would have been run to...

-- which doesn't seem a likely culprit to me).

That said, I am powering freebeast up, and plan to run a manual
full fsck on the "head" slice's root file system....  Maybe a few
others, while I'm here. :-}

Peace,
david
-- 
David H. Wolfskill                              david@catwhisker.org
"Putin is a paranoid dictator.  Putin must go. He started a senseless war
and is leading Russia into a ditch." - Egor Polyakov & Alexandra Miroshnikova

See https://www.catwhisker.org/~david/publickey.gpg for my public key.