Comment # 5 on bug 1137067 from Ross Green

I have just been checking the upstream additions to the drm/nouveau driver
in linus' git tree.

There have not been a lot of new code changes to the nouveau drivers during
May, April, or March.

In fact I had to go all the way back to 2019-02-20 before I found any large
amount of code added to this driver.

So I suspect if this has crept in to the nouveau area it goes way back to at
least kernel 5.0 development or earlier, maybe 4.19 or 4.20.

Of course there may be a problem in more generic code, but on the whole there
has not been a lot of fixes directly to the nouveau area over quite some
period.

Have not had time to go back further than 2019-02-20 kernel changes on linus
git tree.

It may be useful to talk to some of the up stream kernel developers who have
worked in this area. Maybe Ben Skeggs, Colin Ian King, Daniel Vetter, ...

To see if they can shed some more light on this problem. The stack traces may
help the above people understand what might be happening here.

There are lots more people using 4.19+ kernels in other distributions these
days so looking to some of the upstream kernel people could be useful.

Certainly the kernel used in the release Leap 15.1 did not exhibit this
problem.
It is just the latest update where I noticed it. Very obvious, it happens
during boot up. That is to say 4.12.14-lp151.27-default boots but
4.12.14-lp151.28.4-default does not.

The other thing to note is in the earlier 4.12.14-lp151.27-default kernel there
are still freezes that occur during usage. On the whole Leap 15.1 has not been
a happy experience regarding the nouveau driver. I have been using NVIDIA
drivers on other 15.1 systems and have no such freezes.

So there are several problems in this area I suspect. But failing to boot is
obviously the most pressing. ;-)


Ross