Kernel upgrade requires manual "depmod"

[PeterShinners]

After my last three Breezy Badger kernel upgrades, my system has been unable to
enter GDM. This includes the recent 2.6.12-8 that was just released. I am
running with the 686-smp architecture of kernels.

The problem is that the nvidia driver is not being found at startup. The only
way I've been able to fix this is manually running "depmod" from the shell. Once
that is run I can "modprobe nvidia", and restarting GDM. Before running depmod
there seems to be no way I can get the nvidia kernel module loaded.

I'm looking in init.d/module-init-tools now, and seeing the system runs a
"depmod --quick" at boot. But somehow this is not catching it. Note that I also
have "nvidia" listed in my /etc/modules to force it to load.

I mentioned this during the last kernel upgrade on ubuntu-devel. There was no
real information. Matt Zimmerman asked if it could be a clock skew, but I do not
believe that is the problem.

[Matt Zimmerman (mdz)]

(In reply to comment #0)
> I'm looking in init.d/module-init-tools now, and seeing the system runs a
> "depmod --quick" at boot. But somehow this is not catching it. Note that I also
> have "nvidia" listed in my /etc/modules to force it to load.
>
> I mentioned this during the last kernel upgrade on ubuntu-devel. There was no
> real information. Matt Zimmerman asked if it could be a clock skew, but I do not
> believe that is the problem.

Why not?

Did you try removing the --quick? That would actually test whether it is a
clock-related problem.

[Matt Zimmerman (mdz)]

It's entirely possible that depmod --quick isn't appropriate for our
configuration, because it is run before the system clock is set. This means
that we will be comparing timestamps made with a correctly set clock (e.g.,
after installing a kernel) with those made with an uninitialized clock
(S20module-init-tools precedes S22hwclockfirst.sh)

[Matt Zimmerman (mdz)]

*** Bug 20656 has been marked as a duplicate of this bug. ***

[PeterShinners (pete-shinners)]

Perhaps it is a time problem then. I saved my original "modules.dep" from when I
did the install. It has a time of "12:25". The directories that were created for
the modules have the time "12:22". I'm not sure how to test the time without
getting another new kernel install?

Would it be better to ensure that a full "depmod" was run in the post-install
section of any package that installs modules?

[Matt Zimmerman (mdz)]

(In reply to comment #4)

> Would it be better to ensure that a full "depmod" was run in the post-install
> section of any package that installs modules?
>

That's such a fine idea that we retroactively implemented it ;-)

[Daniel Stone (daniels)]

... fixed as per previous comments?

[Matt Zimmerman (mdz)]

(In reply to comment #6)
> ... fixed as per previous comments?

There is clearly still a problem somewhere; the problem simply isn't that we
forgot to run depmod (we do run it).

My best guess is that clock skew is to blame, but this needs further investigation.

ls -al /lib/modules/`uname -r`/{modules.dep,volatile}

from an affected system would be helpful

[PeterShinners (pete-shinners)]

I will run this test next time there is an upgrade. It seems to consistently
have a problem on my system.

[Jack Senechal (jacksenechal)]

I have the same problem, I've got an onboard GeForce4 MX the nvidia-glx drivers.
When I updated to the latest breezy kernel (2.6.12-9-386), it was unable to load
the 'nvidia' module. After reading this I did 'depmod -a' and it fixed it. (This
happened both when I tried an apt-get dist-upgrade to breezy from hoary, and
also later when I clean-installed breezy from the iso, and let the auto-update
upgrade all the packages.)

[Matt Zimmerman (mdz)]

Wolud someone please follow the instructions in comment #7 or make some other
attempt to debug this? Further "me too" reports don't get us any closer to
finding the cause.

[Adam Conrad (adconrad)]

I believe, due to the sorts of reports we're getting, that this is a race and/or
timestamp issue between when we setup lrm on boot and when we run depmod
--quick. That said, I believe this is fixed in version 2.6.12.4-8 of
linux-restriced-modules. If it comes back, please reopen this bug, but it
should be gone for good if you upgrade to the latest version.