nouveau driver does not return VGA connector status breaking upower
Submitted by nuada@agh.edu.pl
Assigned to Nouveau Project
Description
My laptop (Asus UL80VT) has hybrid graphics: intel+nvidia. After switching nvidia card off using vgaswitcheroo, upower CPU consumption goes to 100%. If nvidia card is switched back on, problem dissapeares.
This is caused by nouveau driver not returning VGA connector status properly. When upowerd tries to read status of all connectors, it hangs waiting for VGA.
Gentoo Linux
kernel: 2.6.38-rc*
xorg-server: 1.9.4
upower: 0.9.8
KDE: 4.6.0
Steps to reproduce:
- Log in to KDE
- switch off nvidia:
echo OFF > /sys/kernel/debug/vgaswitcheroo/switch
- cannot read VGA connector status:
cat /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/drm/card1/card1-VGA-1/status