I have RedHat 9 with 2.4.20-8 kernel installed on my computer. Idecided to upgrade it to 2.6. Everything was OK? but after rebooting I saw next message: Kernel panic - not syncing: No init found. Try passing init=option to kernel. What can it be?

How did you make the new kernel?

I upgraded to 2.6.11.11 yesterday (Slack 10.0) without problem..
(.tar.gz from kernel.org)
(as root)
# cp /home/geir/linux-2.6.11.11.tar.gz /usr/src
# tar -zxvf linux-2.6.11.11.tar.gz
# cd linux-2.6.11.11
# cp /boot/config-ide-2.4.26 /usr/src/linux-2.6.11.11/.config
# make oldconfig (this takes a little while)
# make bzImage
# make modules
# make modules_install
# cp arch/i386/boot/bzImage /boot/vmlinuz-2.6.11.11
# ln -sf /usr/src/linux-2.6.11.11/System.map /boot/System.map

in lilo.conf added:
image = /boot/vmlinuz-2.6.11.11
root = /dev/hda2
label = 2.6.11.11
read-only

# lilo -v (verbose mode, just more printout in the console)

This did the trick for me.

-Geir