In the Linux kernel, the following vulnerability has been resolved:
drm/nouveau: don't attempt to schedule hpd_work on headless cards
If the card doesn't have display hardware, hpd_work and hpd_lock are
left uninitialized which causes BUG when attempting to schedule hpd_work
on runtime PM resume.
Fix it by adding headless flag to DRM and skip any hpd if it's set.
