prime-select nvidia tries to use nonexisting folder lib32 causing failure to switch graphics card

[Rovanion]

When running prime-select nvidia on 32-bit Ubuntu 16.04, the following is the output:

```
$ LC_ALL=C sudo prime-select nvidia
Info: the current GL alternatives in use are: ['nvidia-361-prime', None]
Info: the current EGL alternatives in use are: ['nvidia-361-prime', None]
Info: selecting nvidia-361 for the nvidia profile
update-alternatives: using /usr/lib/nvidia-361/ld.so.conf to provide /etc/ld.so.conf.d/i386-linux-gnu_GL.conf (i386-linux-gnu_gl_conf) in manual mode
update-alternatives: warning: skip creation of /usr/lib32/vdpau/libvdpau_nvidia.so.1 because associated file /usr/lib32/nvidia-361/vdpau/libvdpau_nvidia.so.1 (of link group i386-linux-gnu_gl_conf) doesn't exist
update-alternatives: warning: skip creation of /usr/lib32/libvdpau_nvidia.so because associated file /usr/lib32/nvidia-361/vdpau/libvdpau_nvidia.so (of link group i386-linux-gnu_gl_conf) doesn't exist
update-alternatives: using /usr/lib/nvidia-361/ld.so.conf to provide /etc/ld.so.conf.d/i386-linux-gnu_EGL.conf (i386-linux-gnu_egl_conf) in manual mode
```

The important part is "file /usr/lib32/nvidia-361/vdpau/libvdpau_nvidia.so.1 doesn't exist" which is entirely true since there is no folder /usr/lib32 on my system. I figure that /usr/lib32 exists on 64-bit systems with ia32-libs installed and that this program has simply never been tested on a 32-bit machine.

The machine in question has nvidia-prime 0.8.2 installed. What I expected to happen when I ran prime-select nvidia was of course that the proprietary nvidia driver would be used as the display driver on my next reboot - something which doesn't happen. Instead the open source Intel driver is used.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: nvidia-prime 0.8.2
Uname: Linux 4.5.0-040500-generic i686
NonfreeKernelModules: ctr ccm msr cdc_mbim cdc_ncm cdc_acm cdc_wdm usbnet mii uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_v4l2 videobuf2_core videodev media btusb btrtl btbcm btintel bluetooth binfmt_misc drbg ansi_cprng dm_crypt arc4 iwldvm intel_rapl x86_pkg_temp_thermal snd_hda_codec_conexant snd_hda_codec_generic intel_powerclamp mac80211 crc32_pclmul snd_hda_intel aesni_intel aes_i586 xts snd_hda_codec lrw gf128mul snd_hda_core ablk_helper cryptd joydev snd_hwdep input_leds iwlwifi snd_seq_midi snd_seq_midi_event serio_raw snd_pcm thinkpad_acpi snd_rawmidi nvram cfg80211 snd_seq lpc_ich snd_seq_device snd_timer mei_me snd mei soundcore wmi shpchp mac_hid kvm_intel kvm irqbypass cuse coretemp parport_pc ppdev lp parport autofs4 hid_generic usbhid hid i915 i2c_algo_bit drm_kms_helper syscopyarea sysfillrect psmouse sysimgblt ahci fb_sys_fops e1000e libahci drm ptp pps_core fjes video
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: i386
Date: Mon Jun 13 14:43:28 2016
EcryptfsInUse: Yes
InstallationDate: Installed on 2013-08-07 (1040 days ago)
InstallationMedia: Ubuntu 12.04.2 LTS "Precise Pangolin" - Release i386 (20130213)
SourcePackage: nvidia-prime
UpgradeStatus: Upgraded to xenial on 2016-03-17 (87 days ago)

[Rovanion (rovanion-luckey)]

Addendum:

apt-file search /usr/lib32/vdpau/libvdpau_nvidia.so.1

returns nothing. But

apt-file find libvdpau_nvidia.so.1

returns

nvidia-304: /usr/lib/nvidia-304/vdpau/libvdpau_nvidia.so.1
nvidia-304-updates: /usr/lib/nvidia-304-updates/vdpau/libvdpau_nvidia.so.1
nvidia-340: /usr/lib/nvidia-340/vdpau/libvdpau_nvidia.so.1
nvidia-340-updates: /usr/lib/nvidia-340-updates/vdpau/libvdpau_nvidia.so.1
nvidia-361: /usr/lib/nvidia-361/vdpau/libvdpau_nvidia.so.1
nvidia-361-updates: /usr/lib/nvidia-361-updates/vdpau/libvdpau_nvidia.so.1

where nvidia-361 is installed on my system. In other words: The path prime-select uses should read "/usr/lib/nvidia-361/vdpau/libvdpau_nvidia.so.1" and not " /usr/lib32/nvidia-361/vdpau/libvdpau_nvidia.so.1".

[Rovanion (rovanion-luckey)]

So I tried debugging the issue by inserting some print statements into the script on every call to update-alternatives --set, but I seem to be missing the crucial calls in some way:

$ LC_ALL=C sudo prime-select nvidia
Info: the current GL alternatives in use are: ['nvidia-361-prime', None]
Info: the current EGL alternatives in use are: ['nvidia-361-prime', None]
Info: selecting nvidia-361 for the nvidia profile
('gl_alternative:', '/usr/lib/nvidia-361/ld.so.conf')
('In set_alternatives, path is:', '/usr/lib/nvidia-361/ld.so.conf')
update-alternatives: using /usr/lib/nvidia-361/ld.so.conf to provide /etc/ld.so.conf.d/i386-linux-gnu_GL.conf (i386-linux-gnu_gl_conf) in manual mode
update-alternatives: warning: skip creation of /usr/lib32/vdpau/libvdpau_nvidia.so.1 because associated file /usr/lib32/nvidia-361/vdpau/libvdpau_nvidia.so.1 (of link group i386-linux-gnu_gl_conf) doesn't exist
update-alternatives: warning: skip creation of /usr/lib32/libvdpau_nvidia.so because associated file /usr/lib32/nvidia-361/vdpau/libvdpau_nvidia.so (of link group i386-linux-gnu_gl_conf) doesn't exist
('egl_alternative:', '/usr/lib/nvidia-361/ld.so.conf')
('In set_alternatives, path is:', '/usr/lib/nvidia-361/ld.so.conf')
update-alternatives: using /usr/lib/nvidia-361/ld.so.conf to provide /etc/ld.so.conf.d/i386-linux-gnu_EGL.conf (i386-linux-gnu_egl_conf) in manual mode

Could it be that the issue isn't at all what I believe it to be. That the warnings update-alternatives give are not related to the issue?

[Rovanion (rovanion-luckey)]

As you can see none of the three above logs contain any mention of nvidia. It doesn't seem like there is any attempt at all to load the nvidia module.