[arch-general] kernel 3.7.2 - fails to boot - please help

[Genes Lists]

  	Using testing repos - was fully updated and all working fine. Then 
picked up the latest 3.7.2-1 kernel along with kdebase 4.9.5-2/

         Rebooting after this latest update fails - it cannot find the 
root device and drops to "recovery shell".

   	ls /dev/sdb1 (the usual root device) is def missing at that point.

	The recovery option does not boot either.

What I tried:

	I booted 2013.01.04 arch install media - did a chroot as per the wiki - 
and attempted to roll back the kernel using pacman on the 3.7.1 package

         I get several errors:

	warning could not get filesystem information for things like:

		/run/archiso/bootmnt
        		/sys/fs/cgroup/systemd

       /run is empty - and /sys/fs/cgroup is empty

	As per the chroot wiki /sys is mounted from the install via
	mount -t sysfs sys sys/

         pacman continues beyond these warnings but fails with:
==> building image from preset: 'default'
  ->  -k /boot/vmlinux-linux -c /etc/mkinitcpio.conf -g 
/boot/initramfs-linux.img
ERROR: invalid kernel specified: '/boot/vmlinux-linux'

same error from ;fallback'.


	I am hoping I can install 3.7.1 kernel and boot again - instead of a 
new install.

	If anyone can offer some guidance I'd be appreciative ...

thank you

gene