[arch-general] Handling GeForce GTX 850M GPU on Arch Linux

[caocoa at mail2tor.com]

Hello all,

I've juste installed a new computer and I feel like I'm having trouble
with my NVIDIA GPU but it could be something else so I've enclosed
detailed output. As you can see in [lspci] output, my GPU is `NVIDIA
Corporation GM107M [GeForce GTX 850M] (rev a2)` whose specification can be
found in [specs].

The trouble I'd like to solve has the following symptoms:
 → Sometimes during booting process, it issues a lot of lines like
`nouveau E[   PFIFO][0000:01:00.0] SCHED_ERROR [ UNK06 ]` (see [dmesg]
output for full details). This seems to appear randomly: somtimes it has
to reboot two or three times before being able to boot correctly,
sometimes it just needs once and doesn't have nay troubles.
→ Some other times, windows appears to stop responding with no
reasons. I have to mouse the pointer off so the window display will
unfreeze and then I can put the pointer over again. I've found it seems to
be related to lines like this one `nouveau E[   PIBUS][0000:01:00.0] HUB0:
0x000001 0x00000002 (0xbad00100)` in [dmesg]. It starts at timestamp
28.115820.
→ Sometimes, even the window manager (Gnome) freezes and I have to
go to a tty to have a chance to get it unfreeze. It doesn't always work
then sometimes I have to reboot my computer because it has become
absolutely frozen (no mouse, no keyboard, even the keyboard CAPS light
responds no more).
→ Finally, in Arch Linux I've become used to have X server started
over tty1 and tty from 2 to 7 free. Actually, when startup reaches the end
without faults, it start X server on tty1 then GDM (Gnome Display Manager)
is shown on tty1 but once I log in to my account, my desktop is shown on
tty2 and tty1 keeps displaying GDM.

I'm quite puzzled by this and I don't know whether the last symptom is a
bug or a feature (maybe multiple user simultaneous outputs). I've also
enclosed for your information my [Xorg.0.log] file and [lsmod] output. If
it's a bug, which software should I fill a bug report to? nouveau driver,
X, GDM, Gnome?

Just feel free to ask any further data you'd need about my configuration.

Thank you in advance for you reply and have a good weekend!

Caocoa

--- references
[lspci] https://pastee.org/mtwkr
[specs] http://www.geforce.com/hardware/notebook-gpus/geforce-gtx-850m
[dmesg] https://pastee.org/zd4tt
[lsmod] https://pastee.org/t5z4e
[Xorg.0.log] https://pastee.org/r5tak