[SOLVED] Lost peripheral function after linux upgrade 4.20.4 -> 5.0

ayng · 2019-03-10 07:06:15

I set up a new Arch Linux installation back in January 27 of this year. I haven't booted the computer since then until today, March 9. I had only just finished getting through the installation guide, and I hadn't installed any packages yet. At this point, nothing seemed out of the ordinary.

Today, March 9, I did an upgrade with `pacman -Syu`. I noticed that the Linux kernel was being upgraded from 4.20.4 to 5.0. After upgrade, I did a reboot just to make sure nothing broke. Alas, several unexpected things happened on boot.

First, I noticed my monitor did not automatically adjust its resolution as it normally does after showing some of dmesg. Instead, it showed some of dmesg, then jumped to the login prompt rather quickly and without changing resolutions. I tried replugging my monitor but this didn't change the status quo.
Thinking nothing of this, I tried to log in, but my keyboard was not working. My keyboard input was being ignored. The cursor on the login prompt was flashing, so it couldn't have been a display issue. I tried plugging my keyboard into every available port, but none worked.
I tried to reboot again (using a forced shutdown) but nothing changed.

After this traumatic incident I got out my live USB and chroot-ed into my Arch installation to look for clues. I looked through dmesg and journalctl but could not find anything out of the ordinary. That is, I glanced over the logs from January 27 and from March 9 and didn't see any warnings/errors from March 9 that didn't also appear on January 27.

I went through the forums looking for similar experiences, and though I did not find any experiences matching mine, I got the idea that maybe the kernel upgrade was causing problems. While chroot-ed, I downgraded linux back to 4.20.4 and rebooted. Luckily that fixed both the keyboard and monitor issues so I could log in once more.

I should mention that I seem to remember the login prompt post-upgrade still showed "4.20.4" and not "5.0", oddly enough. I don't know what to make of that; maybe I'm misremembering.

Any tips on finding out what exactly went wrong? And more broadly, how can I avoid breaking my system so badly in the future?

My relevant hardware:

GPU: EVGA GTX 760
Motherboard: Asus P8H61-I R2.0

Last edited by ayng (2019-03-11 01:37:05)

jasonwryan · 2019-03-10 07:10:29

Paste the output of `pacman -Q linux && uname -a`, and if they don't match, your /etc/fstab

Morn · 2019-03-10 11:18:11

ayng wrote:

Any tips on finding out what exactly went wrong? And more broadly, how can I avoid breaking my system so badly in the future?

You could use the linux-lts kernel instead. The 5.0 kernel seems to have some major bugs at the moment.

ayng · 2019-03-11 01:34:33

jasonwryan wrote:

Paste the output of `pacman -Q linux && uname -a`, and if they don't match, your /etc/fstab

This is what I get when I'm logged into my system with linux downgraded to 4.20.4.

$ pacman -Q linux
linux 4.20.4.arch1-1
$ uname -a
Linux <hostname> 4.20.4-arch1-1-ARCH #1 SMP PREEMPT Wed Jan 23 00:12:22 UTC 2019 x86_64 GNU/Linux

I have a feeling that's not what you were looking for, so I also tried to upgrade to 5.0 again and I ran into the same issues (keyboard input ignored, monitor resolution did not adjust). Can confirm that the login prompt shows 4.20.4 despite supposedly being on 5.0, which is still a mystery to me. Couldn't log in directly so I used arch-chroot from a live USB and the output is:

$ pacman -Q linux
linux 5.0.arch1-1
$ uname -a
Linux <hostname> 4.20.0-arch1-1-ARCH #1 SMP PREEMPT Mon Dec 24 03:00:40 UTC 2018 x86_64 GNU/Linux

I suppose uname here is describing the kernel installed on the live USB though, so not sure how much this reveals about my borked system.

My /etc/fstab is a little too elaborate to transcribe in full, but here's the gist of it:

# /dev/sda2 LABEL=arch_os
UUID=<stuff>    /    ext4    rw.relatime    0 1

# /dev/sda3 LABEL=swap
UUID=<more-stuff>    none    swap    defaults,pri=-2 0 0

Morn wrote:

You could use the linux-lts kernel instead. The 5.0 kernel seems to have some major bugs at the moment.

Ah, thank you for the suggestion. I did not know about alternatives to the stable linux kernel.

Incidentally, while reading about the alternative kernels I noticed that 5.0.1 came out today (it's still in testing, not core, for Arch Linux) so on a whim I decided to try upgrading to 5.0.1 and lo and behold, all of my issues went away! That made my day. Thank you both for helping me out, I appreciate it

jasonwryan · 2019-03-11 01:43:01

My money is on a separate /boot partition that is not in your fstab and therefore was not mounted for the upgrade. If that is the case, you'll need to fix it and clean up the phantom /boot

ayng · 2019-03-11 02:07:33

jasonwryan wrote:

My money is on a separate /boot partition that is not in your fstab and therefore was not mounted for the upgrade. If that is the case, you'll need to fix it and clean up the phantom /boot

Ah, I think you're right. When I was downgrading to 4.20.4 I did it from my live USB where I was careful to manually mount my boot directory. When I was upgrading to 5.0.1 I also did it after manually mounting my boot partition.

I tried downgrading from 5.0.1 to 5.0 from my live USB once again after manually mounting my boot partition and it worked great. No keyboard/monitor issues and I'm able to log in.

Thanks so much for clearing that up. I'll try to fix my fstab and phantom /boot and report back.

ayng · 2019-03-11 02:37:11

ayng wrote:

jasonwryan wrote:
My money is on a separate /boot partition that is not in your fstab and therefore was not mounted for the upgrade. If that is the case, you'll need to fix it and clean up the phantom /boot
Ah, I think you're right. When I was downgrading to 4.20.4 I did it from my live USB where I was careful to manually mount my boot directory. When I was upgrading to 5.0.1 I also did it after manually mounting my boot partition.
I tried downgrading from 5.0.1 to 5.0 from my live USB once again after manually mounting my boot partition and it worked great. No keyboard/monitor issues and I'm able to log in.
Thanks so much for clearing that up. I'll try to fix my fstab and phantom /boot and report back.

Wonderful, things seem to be in order.

From a live USB, I mounted my root partition and then my boot partition. I did a genfstab to confirm that there were indeed 3 entries now instead of 2, and replaced my old fstab. I then chroot-ed into my system and downgraded linux to 4.20.4. I exited the chroot and unmounted just the boot partition and saw that there was another boot directory hiding beneath, which contained some of the files in the actual boot partition, but not all. I deleted that. Rebooted into system. No issues logging in. Saw boot partition was in fact mounted.

In my system, I upgraded linux once more from 4.20.4 to 5.0. Rebooted into system. No issues. Login prompt shows 5.0 as expected, unlike before.

I guess while doing the initial installation, I had neglected to mount my boot partition before running genfstab. Can't remember exactly at this point, but seeing as I didn't know how fstab worked before this incident, I probably thought nothing of it.

Thank you for your help and patience jasonwryan.

jasonwryan · 2019-03-11 02:39:51

No problem. Glad you have arrived at the long term fix!

Arch Linux

#1 2019-03-10 07:06:15

[SOLVED] Lost peripheral function after linux upgrade 4.20.4 -> 5.0

#2 2019-03-10 07:10:29

Re: [SOLVED] Lost peripheral function after linux upgrade 4.20.4 -> 5.0

#3 2019-03-10 11:18:11

Re: [SOLVED] Lost peripheral function after linux upgrade 4.20.4 -> 5.0

#4 2019-03-11 01:34:33

Re: [SOLVED] Lost peripheral function after linux upgrade 4.20.4 -> 5.0

#5 2019-03-11 01:43:01

Re: [SOLVED] Lost peripheral function after linux upgrade 4.20.4 -> 5.0

#6 2019-03-11 02:07:33

Re: [SOLVED] Lost peripheral function after linux upgrade 4.20.4 -> 5.0

#7 2019-03-11 02:37:11

Re: [SOLVED] Lost peripheral function after linux upgrade 4.20.4 -> 5.0

#8 2019-03-11 02:39:51

Re: [SOLVED] Lost peripheral function after linux upgrade 4.20.4 -> 5.0

Board footer