Fedora Kernel update causes: mkrootdev expected fs options

I'm mainly dropping this somewhere so other people can find it, I recently did a kernel update and when I rebooted I got:

mkrootdev expected fs options
mount: missing mount point
setuproot: moving /dev/failed no such file or directory
setuproot: error mounting /proc
setuproot: error mounting /sys
switchroot: mount failed No such file or directory
kernel panic

...it turns out this was because I'd somehow got two / entries in /etc/fstab, as I found from this posting. The only thing you need to be aware of is that you also have a copy of /etc/fstab in the initrd, so after fixing /etc/fstab you'll want to re-run the postinstall scriptlet (rpm -q --scripts kernel), Ie. /sbin/new-kernel-pkg --package kernel --mkinitrd --depmod --install <kernel version>