apt-get update, apt-get upgrade, and now system fails to boot

[David Christensen <dpchrist@holgerdanske.com>]

debian-user:

I have an Intel DQ67SW motherboard with Intel i7-2600S processor and 
have installed debian-6.0.5-amd64 and the 3.2 kernel from backports.


I ran "apt-get update" and "apt-get upgrade" yesterday.  Since then, the 
system fails to boot:

    Loading Linux 3.2.0-0.bpo.2-amd64 ...
    Loading initial ramdisk ...
    Loading, please wait...
    Gave up waiting for root device.  Common problems:
     - Boot args (cat /proc/cmdline)
       - Check rootdelay= (did the system wait long enough?)
       - Check root= (did the system wait for the right device?)
     - Missing modules (cat /proc/modules; ls /dev)
    ALERT!  /dev/mapper/sda2_crypt does not exist.  Dropping to a shell!


    Busybox v1.17.1 (Debian 1:1.17.1-8) built-in shell (ash)
    Enter 'help' for a list of built-in commands.

    /bin/sh: can't access tty; job control turned off
    (initramfs)


When I enter "cat /proc/cmdline":

    BOOT_IMAGE=/vmlinuz-3.2.0-0.bpo.2-amd64 root=/dev/mapper/sda2_crypt 
ro quiet


When I enter "cat /proc/modules", I see many lines of the form:

    usbhid 39946 0 - Live 0xffffffffa0153000
    ...


When I enter "ls /dev/sda*":

    /dev/sda   /dev/sda1   /dev/sda2


When I enter "ls /dev/mapper":

    control


Any suggestions?


TIA,

David