Created attachment 75867 [details]
screenshot of the crash

echo OFF > /sys/kernel/debug/vgaswitcheroo/switch

causes a null ptr deref at shurdown in this hybrid graphics laptop.

01:00.0 VGA compatible controller: NVIDIA Corporation GF108 [GeForce GT 540M]
(rev a1)

00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core
Processor Family Integrated Graphics Controller (rev 09)

It used to work fine in 3.6 , it broke at some point after 3.7 and continues to
be broken in 3.8 or in 3.9.

The attached file has a screen caputure of the crash.