kernel-3.19.3-200.fc21.x86_64 fails to boot

[Patrick O'Callaghan]

kernel-3.19.3-200.fc21.x86_64
kmod-nvidia-3.19.3-200.fc21.x86_64-346.47-2.fc21.4.x86_64

The failure happens immediately after selecting the kernel from the boot
menu. A stack trace appears which I'll post if someone tells me how to
capture it.

poc