Re: chroot into a debootstrap filesystem and the numerous problems
On Sat, 2025-09-06 at 18:23 -0400, Dennis Clarke wrote:
> On 9/6/25 16:24, John Paul Adrian Glaubitz wrote:
> > Hi,
> >
> > On Sat, 2025-09-06 at 15:08 -0400, Dennis Clarke wrote:
> > > Well firstly I am thankful for the documentation. This is a highly
> > > functional maillist lately. Well, the debootstrap process went amazingly
> > > smooth :
> >
> > You're welcome. I'm only answering briefly for today because I have backpain
> > and need some rest for the remainder of the day.
> >
>
> I can relate. This whole "age" thing has a long term cost.
I slept in bad position during the previous night. Muscles don't like that.
> > > [ 23.133458] Kernel panic - not syncing: VFS: Unable to mount root fs
> > > on unknown-block(0,0)
> > > [ 23.242118] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted
> > > 6.12.3-sparc64-smp #1 Debian 6.12.3-1+sparc64
> > > [ 23.370232] Call Trace:
> > > [ 23.402325] [<0000000000ef8e70>] dump_stack+0x8/0x18
> > > [ 23.467584] [<0000000000eeb430>] panic+0xf4/0x398
> > > [ 23.529407] [<00000000013af7f4>] mount_root_generic+0x1cc/0x268
> > > [ 23.607236] [<00000000013afa1c>] mount_root+0x18c/0x19c
> > > [ 23.675914] [<00000000013afc4c>] prepare_namespace+0x220/0x25c
> > > [ 23.752597] [<00000000013af218>] kernel_init_freeable+0x284/0x29c
> > > [ 23.832713] [<0000000000ef9c08>] kernel_init+0x18/0x12c
> > > [ 23.901390] [<00000000004060c8>] ret_from_fork+0x1c/0x2c
> > > [ 23.971217] [<0000000000000000>] 0x0
> > > [ 24.018204] Press Stop-A (L1-A) from sun keyboard or send break
> > > [ 24.018204] twice on console to return to the boot prom
> > > [ 24.164596] ---[ end Kernel panic - not syncing: VFS: Unable to mount
> > > root fs on unknown-block(0,0) ]---
> >
> > Skimming through the messages, it does not look like the kernel has any
> > block devices drivers loaded, so it doesn't see your disks. I'm also not
> > seeing the kernel message about unpacking the initramfs, so that's not
> > surprising.
>
> I saw that also. I rebuilt the initrd with every driver I could find.
Did you rebuild the initrd *within* the sparc64 chroot?
> >
> > It should look like this (with a different timestamp, of course):
> >
> > [ 0.960540] Trying to unpack rootfs image as initramfs...
> >
> > Did you verify that the symbolic links in silo.conf point to the correct
> > vmlinux and initrd images?
> >
> > You have:
> >
> > # cat silo.conf
> > root=/dev/sdb4
> > partition=1
> > default=Linux
> > read-only
> > timeout=100
> >
> > image=/vmlinux
> > label=Linux
> > initrd=/initrd.img
> >
> > root=UUID=61ac8441-3afa-4ed1-99b6-8278877bda12
> >
> > Notice that you specified "root=" twice. Try putting the one with the UUID
> > into line 1.
> >
>
> I was very careful with that. Over and over and over. I can boot the
> 3.2.0 Linux stuff no problem. I have been trying all manner of
> combinations with silo.conf and generally I see a "Fast Data MMU miss"
> error or I see some other silo early boot problem.
Well, you obviously missed the part where you specific root= twice ;-).
> > Also, where do /vmlinux and /initrd.img point to? They need to point to the kernel
> > and initrd image that you want to load. Please make sure those are not dangling
> > symlinks.
> >
>
> I was very careful with that.
Are you sure? You have to take great care that silo is able to find both the kernel
and the initrd relative to the root filesystem you specified.
But maybe you should just try to install GRUB. Btw, installing "grub-common" is not
the right package. You need to install grub-ieee1275-bin and grub-ieee1275.
Install GRUB on the second hard disk, which hopefully has a smaller /boot partition,
where the new sparc64 root resides with:
# grub-install --force --skip-fs-probe /dev/sdb1
> > > I suspect that silo.conf can not actually use the UUID data.
> > > Just a guess.
> >
> > You can also try to pass the command on the kernel command line:
> >
> > boot: Linux initrd=/boot/initrd.img-6.12.3-sparc64-smp root=UUID=61ac8441-3afa-4ed1-99b6-8278877bda12
> >
>
> Now that looks like a great idea !
Did you try it?
Adrian
--
.''`. John Paul Adrian Glaubitz
: :' : Debian Developer
`. `' Physicist
`- GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913
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