Comment 16 for bug 732149

I am having the same problem since yesterdays updates. Running Kubuntu 11.04 64-bit with btrfs root filesystem. After safe-upgrade I get the follwoing:

$ sudo grub-install /dev/sda
/usr/sbin/grub-probe: error: unknown filesystem.
Auto-detection of a filesystem of /dev/sda1 failed.
Please report this together with the output of "/usr/sbin/grub-probe --device-map="/boot/grub/device.map" --target=fs -v /boot/grub" to <email address hidden>

Please inform if there is anything I can do to help.