Neon unstable kernel dowgrade

[Don B. Cilly]

Updated Neon this morning.
Was using kernel 4.18.0-25.
Now it's using 4.15.0-55.

I checked my /boot/ dir (among other things) , and,

-rw-r--r--  1 root root 58849186 Jul 25 10:28 initrd.img-4.15.0-55-generic
...
-rw-r--r--  1 root root 62134799 Jul 18 20:57 initrd.img-4.18.0-25-generic

It looks like it is today's "update".

Apart from the fact that 4.15 is way past EOL (maintained from January 2018 to April 2018) - well, 4.18 was EOL November 2018 anyway - so much for bleeding edge ;·) ... *
Is this sort of thing common, I wonder. Never noticed it before.

*Yes, I do know the neon unstable bleeding edge refers to plasma, not kernels, but still...

[claydoh]

You got an update to the stock 4.15 but you are still running 4.18.

uname -r

You keep a certain number of kernel versions as backups in Ubuntu, usually 2, but with LTS it can be more. Two of the current kernel and one stock. The 4.15 is the stock 18.04 kernel, but with HWE it is at 4.18, so you'll have the two most recent 4.18s and one 4.15. If you look at your grub menu, the second "advanced" entry opens to show all the different kernels you can boot.

The 4.15 kernel gets regular patches and security fixes, so it may be sort of EOL but many places still need and support it. This one has a short life due to the intel meltdown and spectre bugs. Many situations can't easily just drop in a new kernel (enterprise use cases mostly) so the distros who shipped with 4.15 are supporting it and backporting new fixes from newer kernels.

You can uninstall the 4.15 bits if you wish.

[Don B. Cilly]

Yes I have quite a few (even after autoremove).
Still, if my distro considers the "older kernel" correct, I guess I go with it.
Maybe they had some trouble with the .18 and reverted... or something.

Funny thing though, in the kernel list, I have:

ii  linux-headers-4.15.0-55                       4.15.0-55.60                                all          Header files related to Linux kernel version 4.15.0
ii  linux-headers-4.15.0-55-generic               4.15.0-55.60                                amd64        Linux kernel headers for version 4.15.0 on 64 bit x86 SMP
ii  linux-headers-4.18.0-24                       4.18.0-24.25~18.04.1                        all          Header files related to Linux kernel version 4.18.0
ii  linux-headers-4.18.0-24-generic               4.18.0-24.25~18.04.1                        amd64        Linux kernel headers for version 4.18.0 on 64 bit x86 SMP
ii  linux-headers-4.18.0-25                       4.18.0-25.26~18.04.1                        all          Header files related to Linux kernel version 4.18.0
ii  linux-headers-4.18.0-25-generic               4.18.0-25.26~18.04.1                        amd64        Linux kernel headers for version 4.18.0 on 64 bit x86 SMP

Then as as "generic unnumbered":

ii  linux-headers-generic                         4.15.0.55.57                                amd64        Generic Linux kernel headers
ii  linux-headers-generic-hwe-18.04               4.18.0.25.74                                amd64        Generic Linux kernel headers

Both the .15 and the .18, but it uses the .15 anyway... bah, just confused, not worried.

[EDIT] Ah. sorry, missed the question:

~$ uname -a
Linux all 4.15.0-55-generic #60-Ubuntu SMP Tue Jul 2 18:22:20 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

[claydoh]

Yes I have quite a few (even after autoremove).


Funny thing though, in the kernel list, I have:

ii  linux-headers-4.15.0-55                       4.15.0-55.60                                all          Header files related to Linux kernel version 4.15.0
ii  linux-headers-4.15.0-55-generic               4.15.0-55.60                                amd64        Linux kernel headers for version 4.15.0 on 64 bit x86 SMP
ii  linux-headers-4.18.0-24                       4.18.0-24.25~18.04.1                        all          Header files related to Linux kernel version 4.18.0
ii  linux-headers-4.18.0-24-generic               4.18.0-24.25~18.04.1                        amd64        Linux kernel headers for version 4.18.0 on 64 bit x86 SMP
ii  linux-headers-4.18.0-25                       4.18.0-25.26~18.04.1                        all          Header files related to Linux kernel version 4.18.0
ii  linux-headers-4.18.0-25-generic               4.18.0-25.26~18.04.1                        amd64        Linux kernel headers for version 4.18.0 on 64 bit x86 SMP

These are not kernels, but the headers. Not everyone needs them, but a lot do (Nvidia and Virtualbox users, at the very least).

Then as as "generic unnumbered":

ii  linux-headers-generic                         4.15.0.55.57                                amd64        Generic Linux kernel headers
ii  linux-headers-generic-hwe-18.04               4.18.0.25.74                                amd64        Generic Linux kernel headers

Both the .15 and the .18, but it uses the .15 anyway... bah, just confused, not worried.

[EDIT] Ah. sorry, missed the question:

~$ uname -a
Linux all 4.15.0-55-generic #60-Ubuntu SMP Tue Jul 2 18:22:20 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

You probably booted to the 4.15 at some point. I believe that whatever kernel you boot to becomes the default, but I am not positive. You should be able to select the 4.18 in grub, if yours isn't still wonky.

[Don B. Cilly]

They're the headers, but the images list is the same.
I can boot the .18, but as I said, if Neon decided to downgrade to the .15 instead, they probably have their reasons.
Both seem to work just fine for me, but what do I know.
It was installed today, see my original post directory listing.

(oh, and if you could change the post title, I'd appreciate it

[claydoh]

As I mentioned, It was not a downgrade, it was an update to your existing 4.15.

[Snowhog]

(oh, and if you could change the post title, I'd appreciate it

You can do that yourself. Click on Edit Post and then click on Go Advanced. That gives you access to the thread title.

Added:

You do this on the first post of the thread.

[Don B. Cilly]

Thanks

[oshunluvr]

IME, autoremove doesn't wipe the previous kernel. When you jump to a new kernel series, autoremove stops looking at the previous series. You can just manually delete the last kernel of the previous series if you're happy with what you're running.

[Don B. Cilly]

Well, it did wipe a few.
It said so, and the list was longer.

Still, let's see what future updates bring

[vinnywright]

this really is not that strange of an occurrence when one installs a kernel meta package (linux-image-generic-hwe-18.04) , I have a similar thing going on as well ,

ls -la boot
<snip>
-rw-------  1 root root  8294136 Jul  2 14:03 vmlinuz-4.15.0-55-generic
-rw-------  1 root root  8716024 Jun 26 15:50 vmlinuz-5.0.0-20-generic
-rw-------  1 root root  8707832 Jul  4 06:52 vmlinuz-5.0.0-21-generic

however I boot the newest one and could not begin to say one way or another why you do not at this point , and however however I seam to have some updates today ...

The following NEW packages will be installed:
linux-headers-4.15.0-56 linux-headers-4.15.0-56-generic linux-image-4.15.0-56-generic linux-modules-4.15.0-56-generic linux-modules-extra-4.15.0-56-generic linux-tools-4.15.0-56
linux-tools-4.15.0-56-generic

Ha ha , well we will see what we shall see .

VINNY

[Don B. Cilly]

however I boot the newest one and could not begin to say one way or another why you do not at this point

I have no idea. Either
- Neon decided it is the one I should use, or
- I use rEFInd as boot manager, and it thinks it's the newest because it has the latest install date. Or something else...

In any case, it seems to work just fine, so I'll let it be.

[Don B. Cilly]

Just reporting for the record, not worried, complaining or anything.
I use rEFInd as boot manager, and it boots the "latest" kernel for any specific OS - the one it finds with the latest "modified" date.
Which is good, actually, it just looks at the available kernels for the last booted OS, and uses that. No sudo update-refind, nothing.

So Neon insisted that 4.15 was the kernel. Kept updating it.
So even though I had a (few)4.18(s), it booted that. Well, all right then.

Yesterday I "got bored". Went to /boot and "touched" the .18.
Sure enough, it then booted the .18.
And sure enough, next update, I got a 5.0.0-23.

Except the "modified" date on it - even though it had been compiled after the "touching" of the 4.18 - was older. So it booted the 4.18.
I touched the 5.0, and all's well.

So, Neon now has a 5.x kernel. Nice