Comment 275 for bug 1268257

First of all, it's really sad that this bug is more than one year old, with thousands of people affected (including on LTS releases), and we still don't see any official Canonical communication AFAIK !

It's also a mystery why this bug can apparently take so many different forms. In my case, I do get the DKMS error messages during kernel update :

#####
run-parts: executing /etc/kernel/postinst.d/dkms 3.13.0-49-lowlatency /boot/vmlinuz-3.13.0-49-lowlatency
Error! Bad return status for module build on kernel: 3.13.0-49-lowlatency (x86_64)
Consult /var/lib/dkms/nvidia-331/331.113/build/make.log for more information.
...
Error! Problems with depmod detected. Automatically uninstalling this module.
DKMS: Install Failed (depmod problems). Module rolled back to built state.
#####

But when I check inside /var/lib/dkms/nvidia-331, the nvidia module seems to have been compiled anyway (module file is different from that of previous kernel version). Plus, it's precisely that last compiled module that gets copied to /lib/modules and loaded at boot ... and my machine has always been able to reboot without problem since those compilation errors started occurring.

However, I wanted to write here because I see most people blaming NVidia, but I'm not sure they're alone on this.

I have done some research in my machine's logs and the chronology of events looks like this :

[2014-08-01] fresh install of 14.04 LTS with kernel 3.13.0-24 + NVidia 331.38
[2014-12-15] kernel 3.13.0-43 brings update from NVidia 331.38 to 331.113 + 331.113-uvm (both modules got built by DKMS for kernel 3.13.0-43 and former 3.13.0-40, without error)
[2015-01-16] first DKMS compilation error occurs when updating to kernel 3.13.0-44 ... and has systematically occurred at each kernel update since then.

In short, it's not NVidia's module update that first triggered the error, it's a kernel update !

Anyway, let's hope for the best. I saw last month that NVidia 346 branch had been fixed, and today, that also is branch 340. I guess Canonical is now working hard with NVidia to back-port fix down to branch 331.

Many thanks to you guys :-)