Found a solution, thanks to this: http://nouveau.freedesktop.org/wiki/Optimus/
First, you have to add "drm.rnodes=1" to the kernel parameters: https://wiki.ubuntu.com/Kernel/KernelBootParameters Then, you need to make sure you (the user) are in the video group: sudo usermod -a -G video <user> Reboot, and it should work. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to xorg in Ubuntu. https://bugs.launchpad.net/bugs/1388647 Title: DRI_PRIME=1 has no effect in Ubuntu 14.10 Status in “xorg” package in Ubuntu: Confirmed Bug description: On an Optimus laptop with both GPUs enabled, having run this command so that the Nvidia GPU can be used to offload 3D work from the Intel GPU: ``` xrandr --setprovideroffloadsink nouveau Intel ``` Then running this command: ``` DRI_PRIME=1 glxinfo | grep "OpenGL vendor string" ``` provides the incorrect output: ``` OpenGL vendor string: Intel Open Source Technology Center ``` when it should actually show that the Nouveau driver is in use for the program. This worked previously in Ubuntu 14.04. Apart from only having a 3.16 kernel (instead of 3.17) Ubuntu 14.10 actually supports recent enough versions of the requisite packages necesarry to get DRI 3 offloading support, so perhaps this is part of the problem. Or, more likely, I notice a Nouveau failure after startup, and then again after running xrandr commands, for example: ``` [ 170.912483] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready [ 217.550205] thinkpad_acpi: EC reports that Thermal Table has changed [ 223.857442] ACPI Warning: \_SB_.PCI0.PEG_.VID_._DSM: Argument #4 type mismatch - Found [Buffer], ACPI requires [Package] (20140424/nsarguments-95) [ 223.858395] ACPI Warning: \_SB_.PCI0.PEG_.VID_._DSM: Argument #4 type mismatch - Found [Buffer], ACPI requires [Package] (20140424/nsarguments-95) [ 223.860200] nouveau E[ PBUS][0000:01:00.0] MMIO read of 0x00000000 FAULT at 0x002140 [ !ENGINE ] [ 224.654622] thinkpad_acpi: EC reports that Thermal Table has changed [ 825.172094] thinkpad_acpi: EC reports that Thermal Table has changed [ 831.132156] ACPI Warning: \_SB_.PCI0.PEG_.VID_._DSM: Argument #4 type mismatch - Found [Buffer], ACPI requires [Package] (20140424/nsarguments-95) [ 831.133030] ACPI Warning: \_SB_.PCI0.PEG_.VID_._DSM: Argument #4 type mismatch - Found [Buffer], ACPI requires [Package] (20140424/nsarguments-95) [ 831.134832] nouveau E[ PBUS][0000:01:00.0] MMIO read of 0x00000000 FAULT at 0x002140 [ !ENGINE ] ``` Perhaps this is just a regression in either the Nouveau or Intel drivers for my hardware. I'm using a Lenovo T430. I can confirm that I'm able to start the laptop without errors when I only enable the Intel GPU or NVidia GPU separately, and only see this error when both GPUs are enabled simultaneously. Extra Info: 1: Description: Ubuntu 14.10 Release: 14.10 2: N/A 3: The text 'nouveau' should have appeared in the output of the command. 4: The text 'Intel' appeared in the output of the command. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1388647/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
