Is Ubuntu LTS running a DEBUG kernel?

Question

I found this in my system log:

[   14.845195] **********************************************************
[   14.845196] **   NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE   **
[   14.845196] **                                                      **
[   14.845196] ** trace_printk() being used. Allocating extra memory.  **
[   14.845197] **                                                      **
[   14.845197] ** This means that this is a DEBUG kernel and it is     **
[   14.845197] ** unsafe for production use.                           **
[   14.845197] **                                                      **
[   14.845198] ** If you see this message and you are not debugging    **
[   14.845198] ** the kernel, report this immediately to your vendor!  **
[   14.845198] **                                                      **
[   14.845198] **   NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE   **
[   14.845199] **********************************************************

It is labelled "unsafe for production."

But I got my kernel from the LTS repository:

$ uname -a
Linux ubuntupc 4.15.0-66-generic #75-Ubuntu SMP Tue Oct 1 05:24:09 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

It is from linux-image-4.15.0-66-generic (4.15.0-66.75)

Why did a debug kernel end up in Ubuntu's repository?

OS: Ubuntu 18.04.3 LTS

Video Driver: nvidia-driver-440

Answer 1

So, the trace_printk() was not in the kernel itself, but in a (proprietary) module.

In my case, the sep5.ko module was responsible for this kernel notice, and this module is part of the Intel VTune Amplifier suite.

The vtune software had nested itself in /etc/rc0.d/K01sep5 and /etc/rc0.d/K01sep4_1 and after removing those, the kernel notice disappeared.