Re: kernel update broke -current

On Mon, Sep 5, 2022 at 4:21 PM Mark Millard <marklmi@yahoo.com> wrote:

> Warner Losh <imp_at_bsdimp.com> wrote on
> Date: Mon, 05 Sep 2022 20:07:33 UTC :
>
> > On Sun, Sep 4, 2022 at 4:51 PM void <void@f-m.fm> wrote:
> >
> > > On Sun, Sep 04, 2022 at 07:31:59PM +0000, void wrote:
> > > >
> > > >On Sun, 4 Sep 2022, at 19:07, Warner Losh wrote:
> > > >> You need a newer boot loader...
> > > >
> > > >I was thinking - getting latest -current image, booting to it then
> > > >copying the contents of /boot from the image onto the mounted zpool
> ...
> > > >
> > > >feasible?
> > >
> > > Seems only EFI/ needed replacing from a recent snapshot. I thought it
> might
> > > be all of /boot but I was wrong. Thank you Mark!
> > >
> >
> > Yes. You'll need to update EFI/BOOT on your ESP. The rest of /boot is
> > updated
> > when you do an installworld.
>
> One of the oddities of the update sequence instructions is
> the lack of coverage of the likes of:
>
> Load Path: /efi\boot\bootaa64.efi
>
> What step of the sequencing for the overall system update?
> When is such an update required? (Here the example would
> be: Before rebooting when the ZFS pool(s) possibly used to
> boot gain new features?) When is it not required to update
> the loader in the ESP (or analogous)? Even just knowing
> the stage at which one should do the update indicates some
> about when to figure out if an update is needed and so
> prompts to be ready.
>

Today:

make installworld installkernel
mount -t msdos /dev/<mumble-esp> /boot/efi

and then one of three scenarios

(1) You have the old boot1.efi. This will *always* be in
ESP:EFI\BOOT\BOOT${ARCH}.EFI.
(see uefi(8) for the values of ARCH). You can automatically detect this for
most installations
that were done since about FreeBSD 12:
% sudo efivar | grep Boot1
cfee69ad-a0de-47a9-93a8-f63106f8ae99-Boot1Path
cfee69ad-a0de-47a9-93a8-f63106f8ae99-Boot1Dev

In this case you would do:

% sudo cp /boot/boot1.efi /boot/efi/efi/boot/boot${ARCH}.efi and you are
done.

Please note: If your system was installed a long time ago, you should also
check to see if
you have a LoaderPath variable set:
% sudo efivar --utf cfee69ad-a0de-47a9-93a8-f63106f8ae99-LoaderPath
/boot/loader.efi

When Boot1 isn't set and it is set to the above value (or something
similar), then you are
booting with a really old copy of boot1.efi. You will need to update it and
may need to arrange
for a larger ESP since FreeBSD's boot1.efifat was a tiny image that was
hard to grow. Steal
space from swap for a larger ESP, etc. Documenting that is beyond the scope
of this email.

(2) You are booting with loader.efi and it is in the bug-compatibility
place. Some UEFI BIOSes
don't respect or can't set BootXXXX variables set by efibootmgr(8). In that
case, many people
are booting from the 'compatibiltiy' location for removable devices. This
will almost always be
a single boot scenario because you can't easily boot other systems like
this (well, unless 'quit'
works from the OK prompt to go to the next one on the list, but I digress).
You will see something like:

% sudo efivar --utf cfee69ad-a0de-47a9-93a8-f63106f8ae99-LoaderPath
cfee69ad-a0de-47a9-93a8-f63106f8ae99-LoaderPath
\EFI\BOOT\BOOTX64.EFI
(or AA64)

when you are booting this way. In this case the update command is:

% sudo cp /boot/loader.efi /boot/efi/efi/boot/boot${ARCH}.efi

to upgrade. Some people may be doing this already on systems that can
support efibootmgr(8) and
they can of course upgrade to using that, though that's also beyond the
scope of this email.

(3) You are booting on a working system with a FreeBSD installed by the
boot loader, or some other
custom arrangement. In that case, you'll see something like:
sudo efivar --utf cfee69ad-a0de-47a9-93a8-f63106f8ae99-LoaderPath
cfee69ad-a0de-47a9-93a8-f63106f8ae99-LoaderPath
\EFI\FREEBSD\LOADER.EFI

(or some other place for custom setups: I assume if you are doing that you
know enough to
update my instructions as appropriate). To update, you'd do

% sudo cp /boot/loader.efi /boot/efi/efi/freebsd/loader.efi

Automating all these cases is, needless to say, tricky.


> Part of the sequencing gets into having needed to do a
> installworld to have a from-same-build content replacement
> for the likes of /efi\boot\bootaa64.efi . So installkernel
> already done, a reboot already done, and an installworld
> having been done as well in order to have something to
> copy over. (There are no pointers to alternate places to
> get copies that I know of. One can find copies in the
> build tree when one builds from source locally. So waiting
> is not really required for that context.)
>

Yea, I have a branch that has an 'installboot' target that updates the boot
loader regardless, but given the 50-odd combinations of ways we can
boot, it's a bit bogged down.


> This also make it seem that updating ZFS pool features
> should wait until after a system upgrade that spans both
> the loader and kernel being ready for the new features,
> even if compatibility with other systems is not a worry.
>

Yes. ALWAYS update your boot blocks before zpool update.


> Do any of the system upgrade instructions cover such
> relationships? Do any of the ZFS pool upgrade instructions
> cover such? Does zpool or the like suggest such issues
> when it reports there are new features that could be
> enabled?
>

See above. :)


> Part of what I expect happened here was contributed to by
> a lack of being prompted to even think about the relevant
> issues, leading to a pool feature upgrade that had not
> been prepared for.
>

Yea, so far 100% of the 'help, I upgraded and now the boot loader
can't see zfs pool' issues have been 'I didn't upgrade my loader.efi
properly after zpool upgrade.' It was mandatory when we had the
OpenZFS rebase, but it is also necessary every few OpenZFS
updates from upstream as nnew features are enabled.

I'd love for someone to add this information to the handbook, and I'd
happily review such an effort. I have time to do a brain dump, but not
to make it pretty / formatted for asciidoctor and won't for some time.

Warner


> ===
> Mark Millard
> marklmi at yahoo.com
>
>