2.6 Kernel and root=LABEL=/ VFS Kernel Panic

[Net Llama!]

On Thu, 11 Mar 2004, James McDonald wrote:
> I am having trouble with booting my Fedora Core 1 Redhat box when I
> leave the default root=LABEL=/ as shown
>
> title Fedora Core (2.6.3james2)
>         root (hd0,0)
>         kernel /vmlinuz-2.6.3james2 ro root=LABEL=/ hdc=ide-scsi rhgb
>         initrd /initrd-2.6.3james2.img
>
> I get the following.... (this I wrote down and copied here)
>
> RAMDISK: Compressed Image found at block 0
> RAMDISK: incomplete write (-1 != 32768) 4294304
> VFS: Cannot open root device "LABEL=/" or unknown-block(0,0)
> Please append a correct "root=" boot option
> Kernel panic: VFS: Unable to mount rootfs on unknown-block(0,0)
>
> Now I know I have the correct labels on my partitions
>
> sudo /sbin/e2label /dev/hda1
> /boot
> sudo /sbin/e2label /dev/hda2
> /
>
> And my kernel config is as attached
>
> I have noted a reference on google that mentions making sure  RAM File
> system is on and mine are
>
> CONFIG_BLK_DEV_RAM=y
> CONFIG_BLK_DEV_RAM_SIZE=4096
> CONFIG_RAMFS=y
>
> But I still get the kernel panic when using the root=LABEL=/ option
> changing it to root=/dev/hda2 fixes the issue.

Redhat first made this change in RH9 (i believe), and labeled it an
enhancement. I think it sux, because it obscures the real block device
names with fancy labels.  Next thing you know, they'll be calling them
C:\ and D:\.  But I digress.  If you edit /etc/fstab to use the real
device names then you shouldn't need to provide a root= at boot.  There's
prolly a more elegant Redhat way of doing this that allows you to
continue using LABLE= but since i hate that notation anyway, i've not
made any effort in figuring it out.

> As far as I can tell the initrd isn't being loaded properly. I let the
> make all & make modules_install install process install the original initrd
>
> I have just tried
> sudo /sbin/mkinitrd /boot/initrd-2.6.3james2 2.6.3james2 to create a new
> initrd and editing grub.conf to use it and this has not helped
>
> looking at the size of the initrd's I see that the 2.6.3 versions are a
> lot bigger
> du -h initrd-2.*
> 161K    initrd-2.4.22-1.2115.nptl.img
> 161K    initrd-2.4.22-1.2174.nptl.img
> 207K    initrd-2.6.3crypt.img
> 207K    initrd-2.6.3james1.img
> 208K    initrd-2.6.3james2
> 207K    initrd-2.6.3james2.img

2.6.x kernels are bigger than 2.4.x kernels of roughly the same
configuration.  That's normal.

-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Lonni J Friedman				netllama at linux-sxs.org
Linux Step-by-step & TyGeMo		     http://netllama.ipfox.com