Re: GPT boot with ZFS RAIDZ "ZFS: i/o error - all block copies unavailable"

2009/11/12 Robert Noland <rnoland_at_freebsd.org>:
> On Thu, 2009-11-12 at 16:54 -0800, Matt Reimer wrote:
>> 2009/10/15 Radek Valášek <valin_at_buchlovice.org>:
>> > Everything works fine for me, until I rewrite kernel/world after system
>> > upgrade to latest one (releng_8). After this am I no longer able to boot
>> > from zfs raidz1 pool with following messages:
>> >
>> >>/ ZFS: i/o error - all block copies unavailable
>> > />/ ZFS: can't read MOS
>> > />/ ZFS: unexpected object set type lld
>> > />/ ZFS: unexpected object set type lld
>> > />/
>> > />/ FreeBSD/i386 boot
>> > />/ Default: z:/boot/kernel/kernel
>> > />/ boot:
>> > />/ ZFS: unexpected object set type lld
>> > />/
>> > />/ FreeBSD/i386 boot
>> > />/ Default: tank:/boot/kernel/kernel
>> > />/ boot:
>>
>> Radek,
>>
>> Try the attached patch (sponsored by VPOP Technologies). I found an
>> overflow in /sys/cddl/boot/zfs/zfssubr.c:vdev_raidz_read() that was
>> causing my 6x1TB raidz2 array to fail to boot.
...
>> The kernel source for the corresponding functionality is in
>> /sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev_raidz.c:vdev_raidz_map_alloc().
>> There all these variables are uint64_t, but I think unnecessarily. I
>> tried changing the boot loader's vdev_raidz_read() variables to all
>> uint64_t but then gptzfsboot would reboot itself, likely due to a
>> stack overflow. The attached patch just changes a few variables that,
>> after a quick analysis, seemed likely to overflow.
>>
>> If this looks good, would someone commit it?
>
> ps_at_ grabbed it up already, but I may handle the MFC for him.  I have
> some other minor fixups in my tree right now... like teaching printf to
> handle %llx.  Thanks for finding this... It's been really frustrating
> that I couldn't produce a failing system.

Is it possible for this patch to get into 8.0-RELEASE, or is it too
late? I suppose it doesn't matter that much since the loader isn't
built with LOADER_ZFS_SUPPORT by default anyway, so folks are going to
have to compile it themselves.

Matt