LinuxQuestions.org - [SOLVED] "Can't find root filesystem / error mounting /dev/root" when booting to new kernel

I am trying to upgrade my kernel from 2.6.18-274 to 2.6.39 for some wireless card drivers.
When I boot into the new kernel I get the "Can't find root filesystem / error mounting /dev/root" googling led me to this page http://fedoraproject.org/wiki/Common..._.2Fdev.2Froot
From what I am reading seems to be an issue with a driver for my SATA controller or HD, but I can't find what option I need to add to the kernel.
Doing a diff from the old initrd to the new one gives me the following:

Code:

root-> diff /tmp/kafter /tmp/kbefore 

6a7,8

> lib/dm-message.ko

> lib/dm-region_hash.ko

8a11

> lib/dm-raid45.ko

13d15

< lib/dm-region-hash.ko

16a19

> lib/dm-mem-cache.ko

Do I need any of those? not sure if I would need dm-raid45.ko as I am not running a raid.
I have the same SATA and IDE options configured for both kernels so not sure what else to look for, any help is appreciated.

Additionally here is the HW info:

Code:

00:1f.2 IDE interface: Intel Corporation 82801FB/FW (ICH6/ICH6W) SATA Controller (rev 03) (prog-if 8f [Master SecP SecO PriP PriO])

        Subsystem: Hewlett-Packard Company Unknown device 3006

        Flags: bus master, 66MHz, medium devsel, latency 0, IRQ 233

        I/O ports at 1818 [size=8]

        I/O ports at 1830 [size=4]

        I/O ports at 1820 [size=8]

        I/O ports at 1834 [size=4]

        I/O ports at 14f0 [size=16]

        Capabilities: [70] Power Management version 2



root-> smartctl -a /dev/sda

...



=== START OF INFORMATION SECTION ===

Device Model:    WDC WD5000AADS-00S9B0