Re: Kernel panic: VFS: Unable to mount root

[Gene Heskett <gene.heskett@verizon.net>]

On Monday 07 March 2005 07:06, Jimmy B wrote:
>Hi list!
>I just compiled a new kernel version 2.6.8 with sources downloaded
> with apt-get:
>apt-get install kernel-source-2.6.8
>I ran these commands:
>make mrproper
>make menuconfig
>make
>make modules install
>
>I do upgrade-grub and it adds the new kernel to the menu.
>When I rebbot using the new kernel I get a kernel panic:
>kernel panic: VFS: Unable to mount root fs on unknown-block(0.0)
>
>I'm thinking maybe I missed enabling something in 'make menuconfig'
> but maybe I'm wrong? Any suggestions/pointers to what I should be
> looking for would be appreciated.
>
>/Jimmy

Are all the drivers for your disk systems non-modular?  They must be 
built into the kernel if you are not using an initrd.

Also, I've never been able to trust an install script to get it right, 
so make sure your /boot/grub/menu.lst shows the same data after the 
'root' keywords for both the new entry, and the old one.  They mean 
different things in different places.

example:

# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this 
# file
# NOTICE:  You have a /boot partition.  This means that
#          all kernel and initrd paths are relative to /boot/, eg.
#          root (hd0,0)
#          kernel /vmlinuz-version ro root=/dev/hda3
#          initrd /initrd-version.img
default=14
fallback=13
timeout=10
splashimage=(hd0,0)/grub/splash.xpm.gz

[...]

#13
title Red Hat Linux (2.6.11)
     root (hd0,0)
# the above line indicates the /boot partition, in my case the first 
# drive, and the first partition on that drive
     kernel /vmlinuz-2.6.11 ro root=/dev/hda7 elevator=cfq vga=ask
# the root= in the above line means the root of the filesystem, or 
# the / partition.

#14
title Red Hat Linux (2.6.11.1)
     root (hd0,0)
     kernel /vmlinuz-2.6.11.1 ro root=/dev/hda7 elevator=cfq vga=ask
------------------

The above is accurate if you have a seperate '/boot' partition, and 
I've never set up a system without one.

Does this explanation help?

-- 
Cheers, Gene
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