[pkg-nvidia-devel] Bug#583312: possible fix

[Russ Allbery]

Romane <romane at miscellanie.com> writes:

>> I had a look at the open bugs against nvidia-glx, and came across
>> #521699 which seem similar to your problem.  Reassigning to the
>> nvidia-glx package to get input from the maintainers of that package,
>> and because I believe the problem is in that package.  Setting
>> serverity to serious, based on the assumtion that this problem will
>> affect all users with parallel booting now enabled by default.

I think parallel booting is a red herring.  The init script for nvidia-glx
has nothing to do with the operation of the X server (take a look at what
it does).

> You seem to have hit the nail on the head. Added that line to the script
> nvidia-glx, commented out the delay I had added in /etc/kde4/kdm/kdmrc,
> rebooted, and it came up to a normal logon screen without even
> displaying the green nVidia logo. I then went in and made sure
> everything was set back to what it was when this issue started for me -
> took out those two lines from the nvidia-glx script that were tried
> earlier, ensured that numbering was still S17nvidia-glx in
> rc2.d. Rebooted. 6 times. Each time without any errors, without seeing
> the nVidia logo, and boot was acceptably and perceptibly quicker than
> what was before even the update of the initscripts yesterday. Only
> things couldn't change was whatever changes running update-rc.d made
> earlier in the day (see history of problem).

If you're experiencing a variant of #521699, then the problem is that the
timeout in KDM is too fast.  You need to tell KDM to wait longer; it takes
the NVIDIA driver longer to initialize the card than it's willing to wait
for.  I suspect that the only thing that parallel booting is doing is
starting kdm sooner and hence giving the NVIDIA module even less time to
initialize the hardware.

See #568969 for the timeout fix that worked for GDM.  It appears to no
longer be a problem with GDM 3 (or at least it's not reproducible for us).

However, it's possible that my understanding here is not complete.

I don't see any obvious way that we can fix this on the NVIDIA side if I'm
understanding the problem correctly.  It takes as long as it takes to
initialize the video card, and the nvidia-glx init script is superfluous
and is going away, so adding delays to it won't work (and I'm skeptical
that's a reliable solution anyway).

-- 
Russ Allbery (rra at debian.org)               <http://www.eyrie.org/~eagle/>