[issue1407] disklabel64 boot problem

[Matthew Dillon]

:
:New submission from Thomas Nikolajsen <thomas.nikolajsen at mail.dk>:
:
:Booting DragonFly from disklabel64 slice has problems:
: - using HAMMER it almost works: one module can't be read
:Reading /modules/acpi.ko fails; after booting (host can run without ACPI)
:(i.e. by kernel) acpi.ko can be read and contents is correct.
:(files on test HAMMER system are just cpdup'ed from a working system;
:cmp verified acpi.ko is readable and has same contents)

    It sounds like the hammer fs read code in the boot loader isn't
    handling all the cases properly.

:Also doing ls command in loader on HAMMER file system can crash loader.
:It seems like libstand/hammerread has an issue.
:
: - using UFS it doesn't work: I just see a spinning bar
:It doesn't show any text, like BTX..
:
:I had the impression that disklabel64 booting should be working
:(since commits below); is this correct?

    UFS should work.

:Is zeroing slice start before making bootable disklabel still needed?
:If yes: is it enough to zero 16KB, like disklabel32.

    Zeroing is still needed.

:I was going to update disklabel64.8 to include boot info again;
:but will hold it back until this issue is resolved.

    I'm going to be blunt on the HAMMER boot thing... I don't actually
    like the idea, because the boot code can't run the UNDO's after a
    crash and so might not be able to find the kernel and other boot
    related files.  I would rather just boot from a small UFS /boot
    partition and then have the kernel mount HAMMER as the root.

    I guess I'll have to deal with changing the installer to create a
    BOOT+HAMMER setup instead of a straight HAMMER setup.

					-Matt
					Matthew Dillon 
					<dillon at backplane.com>