I downloaded kernel 2.6.6 source, patched 2.6.7-pre2 and compiled as below.

# make
# cp /usr/src/linux-2.6.6/arch/i386/boot/bzImage /boot/vmlinuz-2.6.6
# cp /usr/src/linux-2.6.6/System.map /boot
# make modules_install

After installation kernel image to /boot, I edit /etc/lilo.conf as below and issued command "lilo".

LILO configuration file
# generated by 'liloconfig'
#
# Start LILO global section
boot = /dev/hdc
message = /boot/boot_message.txt
prompt
timeout = 1200
# Override dangerous defaults that rewrite the partition table:
change-rules
reset
# VESA framebuffer console @ 1024x768x256
vga = 791
# Normal VGA console
# vga = normal
# VESA framebuffer console @ 1024x768x64k
# vga=791
# VESA framebuffer console @ 1024x768x32k
# vga=790
# VESA framebuffer console @ 1024x768x256
# vga=773
# VESA framebuffer console @ 800x600x64k
# vga=788
# VESA framebuffer console @ 800x600x32k
# vga=787
# VESA framebuffer console @ 800x600x256
# vga=771
# VESA framebuffer console @ 640x480x64k
# vga=785
# VESA framebuffer console @ 640x480x32k
# vga=784
# VESA framebuffer console @ 640x480x256
# vga=769
# End LILO global section
# Linux bootable partition config begins
image = /boot/vmlinuz-2.6.6
root = /dev/hdc1
label = Linux
read-only

image = /boot/vmlinuz-xfs-2.4.26
root = /dev/hdc1
label = Linux2.4.26
read-only
# Linux bootable partition config ends

After reboot my machine, and select 2.6.7-pre kernel at select screen, my machine indicates

VFS: Cannot open root device "1601" or unknown-block(22,1)

and kernel paniced.

If I try to use 2.4.26 kernel image, it boot up normally.

I upgraded all packages in my machine from slackware-current.
Also, I already try to use /testing/packages/linux-2.6.6/kernel-generic-2.6.6-i486-1 and kernel-modules-2.6.6-i486-1, but same error message occurred.

I use Serial-ATA HDD in my machine, and devide 3 partions as below.

Disk /dev/hdc: 164.6 GB, 164696555520 bytes
255 heads, 63 sectors/track, 20023 cylinders
Units = cylinder of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/hdc1 * 1 9726 78124063+ 83 Linux
/dev/hdc2 9727 19999 82517872+ 83 Linux
/dev/hdc3 20000 20023 192780 82 Linux Swap

hdc1 and hdc2 formatted as XFS.
/dev/hdc1 is /, /dev/hdc2 is /home.

I made XFS driver as included in the kernel, not modules.
Of course, I also made Serial-ATA driver in the kernel, not modules.

My machine's spec is
CPU: Pentium4
M/B: MSI 865PE2 NEO2
Chipset: Intel 865PE
Memory: 1GB

I appreciate any suggestions and comments.

I thought I answered this thread? hmmmm I wanna say I replied with asking if you had all your proper filesystems compiled into the kernel. A kernel may not have the right ones by default.

didn't work.

Try making it a module, just in case it wants to be picky.