2.6 compilation woes...

[Doofus <doofus@bulldoghome.com>]

Hi,

I hope someone can help me out here.
I'm finding 2.6 quite complex compared with the 2.4 kernels which I 
understood and was comfortable with.

I've recently installed sarge over the net and chose kernel 2.6 to 
initially run with. Everything worked well.
I then got the 2.6 source from my debian mirror and did my first 
compilation (make menuconfig, make-kpkg clean, make-kpkg <revision> 
kernel_image, dpkg -i ../*.deb), using the default (and working) .config 
file in /boot as a starting point.

This also went went well even though I still don't fully understand 
every aspect of the source tree.

My problem:
When I choose the newly compiled kernel from the grub boot menu I get, 
early in the boot process:

   Kernel panic: VFS: Unable to mount root fs on unknown-block (0,0)


I resolved to do some more compiles, only making changes to the default 
configuration by one section at a time, in a process-of-elimination 
effort to find where the problem is, but even after the first 
compilation when the only change I'd made was the processor type, I 
still had the same boot failure.

So, I cleaned the source tree and compiled another kernel using the 
completely unmodified .config file that came with the working default 
2.6 sarge installaion. And you guessed it - another kernel panic.

Now I'm bamboozled. If I compile a kernel using the identical .config 
file that was used to compile the working and running kernel and it 
won't boot properly, then my powers of fault finding dry up. I'd be 
mightily grateful if anyone can give me any ideas as to where the 
problem may lie, or other things to try.


Configuration:

Dell Inspiron 8200 P4 laptop
hda1    /boot (ext2)
hda2    WinXP (ntfs)
hda3    FAT32
hda5    /home (reiser)
hda6    / (reiser)
hda7    swap


Original working and new unworking sections of menu.lst:

title        Debian GNU/Linux, kernel 2.6.8-2-686
root         (hd0,0)
kernel       /vmlinuz-2.6.8-2-686 root=/dev/hda6 ro
initrd       /initrd.img-2.6.8-2-686
savedefault
boot


title        Debian GNU/Linux, kernel 2.6.8
root         (hd0,0)
kernel       /vmlinuz-2.6.8 root=/dev/hda6 ro
savedefault
boot


Thanks again for any help offered.