Ubuntu 18.04.2 upgrade -- and whither the kernel?


#1

Mild curiosity.
Here is a recent article in Ziff Davis about the latest Ubuntu version:

In it, one of the features of the upgrade is moving to kernel 4.18 from 4.15.
Well, I have 18.04.2, I update daily, but my kernel is still 4.15.
Did I miss anything? Why haven’t I been invited to the Kernel Party?
Also, it says it includes newer versions of Firefox and Libre. Did I miss another party?


#2

i don’t know if this is the specific reason, but at the top of that article it is listed as being in regards to enterprise software. it would make sense to me that paid customers and especially those running servers would get access to the newer kernel before desktop users.


#3

the link below for the LTS enablement stack seems to indicate (if i am reading it correctly) that 4.18 ships with 18.04.2 new installs:

The 18.04.2 and newer point releases will ship with an updated kernel and X stack by default for the desktop.

but upgrading (your post didn’t say if you installed .2 fresh or upgraded to it) from a previous point release (18.04.1) or previous release (any non-point release before 18.04?) means the system with remain on the GA (general availability) stack. the ga stack sounds like it provides the older, more stable kernel from my reading:

However, if one wants to remain on the original GA (General Availability) stacks, the options are:

  • Install from a previous 12.04.0/12.04.1/14.04.0/14.04.1/16.04.0/16.04.1/18.04.0/18.04.1 point release and update. Previous releases are archived at http://old-releases.ubuntu.com/

  • Perform an update or upgrade to an LTS release from a previous release.

further (bold and italics mine for emphasis):

The Ubuntu LTS enablement (also called HWE or Hardware Enablement) stacks provide newer kernel and X support for existing Ubuntu LTS releases. These enablement stacks can be installed manually but are also available when installing with Ubuntu LTS point release media.

https://wiki.ubuntu.com/Kernel/LTSEnablementStack


#4

Then, help me out.
I went to the website you posted and they offer the following command to update the HWE stack:

sudo apt-get install --install-recommends linux-generic-hwe-18.04 xserver-xorg-hwe-18.04

Is there a reason I should NOT try this out? As @mack would say, it ain’t broke, innit? Is that reason enough to be satisfied with what I got?


#5

in general i nod my head along with a lot of mack’s advice. in this instance on my daily use machine i would definitely lean towards if it ain’t broke; however, i also believe in trying new things and experimenting from time to time :slight_smile: i would say having a backup handy just in case is a good idea.

i did also read another tidbit in the 18.04.2 release notes that said something about hwe truly only being a benefit to newer hardware so i’m not sure what (if any) changes you will notice. i also don’t know how new your hardware is so maybe you will see all of the changes.

i haven’t personally done any kernel upgrades so i can’t point to a definitive reason not to. i also haven’t read anything above and beyond that it can make things messy and kill that particular install. nothing to the degree that it would kill the machine. that being said, let the buyer beware.


#6

i missed this particular question in my response and thought process. as far as the satisfaction part of it goes, i would ask what it is you hope to get out of the upgrade. if there is a feature of the new kernel/xserver that sounds appealing and you feel like you will benefit from it, then it seems like there will be a way to guage your satisfaction if you decide to take the plunge. if the desire is to just make a change and see what happens, i wonder if that satisfaction won’t be harder to measure.


#7

cliffsloane

Is there a reason I should NOT try this out? As @mack would say, it ain’t broke, innit? Is that reason enough to be satisfied with what I got?

Correct.

Unless you have a spare machine to play around with, and can afford mistakes and learn from your errors because things will go Belly Up, for a host reasons, that may or may not be your fault.

Or if you must have the latest shinny thingy. Take heed of above advice.

I only use Back Ported (BPO) kernels through Debian backport repositories, as I recently found the Stable LTS 4.09 kernel on my laptop with Debian, does not co-operate with the Stable LTS 4.19 kernel I have on my ATX sized rig, with Manjaro.

Especially noticeable when transferring data between my USB3 external (encrypted) HDD, with its own power source. It would freeze my Debian desktop and become totally unresponsive, after disconnecting via the “safely remove disk” option or “eject”.

:sunglasses:

Edit 21/02/19 11.25 typo


#8

My 18.10 desktop is running : Kernel: Linux 4.18.0-15-generic

Yesterday I built a Ubuntu 18.04.2 server VM from 18.04.2 “Live” Server ISO *

It was still running kernel 4.15.0-45-generic…

I enabled the HWE kernel (as per @cliffsloane comment above : " sudo apt-get install --install-recommends linux-generic-hwe-18.04") - and I’ve now got :

Welcome to Ubuntu 18.04.2 LTS (GNU/Linux 4.18.0-15-generic x86_64)

Not quite game to try this out on a desktop :wink: just yet…


* boy that’s different from the old debian style text interface installation !!!


#9

As an update : I just built a Bionic Beaver 18.04.2 desktop VM - and it’s got kernel 4.18 by default without intervention…

One thing that kinda stumped me : my desktop machine here, Cosmic Cuttlefish 18.10, is “mitigated” for all of the spectre and meltdown family of vulnerabilities :

SUMMARY: CVE-2017-5753:OK CVE-2017-5715:OK CVE-2017-5754:OK CVE-2018-3640:OK CVE-2018-3639:OK CVE-2018-3615:OK CVE-2018-3620:OK CVE-2018-3646:OK

( using Stephane Lesimple’s script from : https://github.com/speed47/spectre-meltdown-checker )

But my newly build Bionic Beaver 18.04.2 server with HWE updated to latest, running as a guest on my 18.10 desktop is STILL vulnerable to some Spectre/Meltdown variants :

SUMMARY: CVE-2017-5753:OK CVE-2017-5715:OK CVE-2017-5754:OK CVE-2018-3640:KO CVE-2018-3639:KO CVE-2018-3615:OK CVE-2018-3620:OK CVE-2018-3646:KO

And same deal with 18.04.2 “desktop” build with kernel 4.18!

And why on earth would I be running a Hypervisor inside a VM (I know there’s “nested virtualization” - but this is ridiculous!) - as Stephane’s script is finding a hypervisor…

It seems Ubuntu installs KVM by default even in a guest os? Like how Windows 10 foists HIDEOUS HyperV on us (well my work supplied “corporate” laptop has HyperV enforced - which means no VirtualBox or VMware workstation! And HyperV is a ghastly steaming pile of cr@p !)

And here’s what “virt-what” finds in my Bionic desktop VM :

user@beaverdesk:~$ sudo virt-what
virtualbox
kvm

#10

Thank you for the information. I am not entirely sure what it all means, I am sure that some here with greater knowledge will know. I did however, follow the link you gave and do everything suggested and got a not vulnerable result back so that was worth doing.