RE: drm/mgag200: doesn't work in panic context

From: Luck, Tony
Date: Fri Jun 26 2015 - 14:30:48 EST


>> I'm here to report two panics which hang forever (the machine cannot reboot). It is because mgag200 doesn't work in panic context. It sleeps and allocates memory non-atomically.
>
> This is the same for all drm drivers, the drm atomic handling with
> fbcon/fbdev is totally broken. It would be serious work to fix this
> properly.

It's a serious problem when a server crashes ... even worse when it hangs while doing so
because we have to rely on some other agent to notice the hung server and go poke it
with a stick.

If it is too hard to fix all of the drivers, is it possible to attack this in the allocator?

-Tony