[SOLVED] 346.22: driver turns backlight off

346.22 using the modesetting driver and a Quadro K5100M as image source.
All drivers earlier than 346.22 apparently do not touch the /sys/class/backlight/intel_backlight/bl_power value (it must be set to 0 to enable backlight). 346.22 sets this to “4”, keeping the backlight off
when VT 7 is selected. Switching to other console VTs switches the backlight on again.

EDIT: figured it out: Despite the changelog claiming improved compatibility with recent linux
kernels, it’s still necessary to patch it drm set_busid support for optimus configurations.
nvidia-bug-report.log.gz (206 KB)