Arch Linux

gi1242

Member

Registered: 2022-07-07

Posts: 34

System unbootable after upgrade to linux-lts-6.12.58-1

Hi All,

After years of having no trouble with Arch, the upgrade today made my system unbootable.

1. I updated today to linux-lts-6.12.58-1, and the system didn't boot. Bootloader loaded. But I got no console output, no network connection. Ctrl-Alt-Del worked to reboot, but journalctl -b -1 showed no logs from the failed boot. (Failsafe mode did the same thing)

2. I downgraded to linux-lts-6.12.57-1, and had the same behavior.

3. I downgraded further to linux-lts-6.12.56-1 (by downgrading all packages to the state on 2025-11-01, one day before 6.12.57-1 was introduced), and the system booted fine.

How do I go about debugging the problem if I have no console output, and no logs, and no network activity?

Any help would be appreciated. Thanks in advance

GI

gi1242

Member

Registered: 2022-07-07

Posts: 34

Re: System unbootable after upgrade to linux-lts-6.12.58-1

PS: All my other machines upgrade fine to the latest linux-lts. I use similar configurations on all of them (no display manager, autologin console, etc.). The only notable difference on the machine that won't boot is that it has a few docker containers that auto-start, more complex network rules (along with a systemd-networkd-wait-online requirement), more complex partitioning (still all ext4, but one raid array), and slightly different hardware (desktop; intel). I assume if the system isn't getting online, I would at least see console output (or logs), and if the raid array isn't coming online I would also see console output / logs (the main boot partition is not raid).

so something in the boot process seems to be hanging, yet is responsive to the 3 finger salute ctrl-alt-delete

seth

Member

From: Won't reply 2 private help req

Registered: 2012-09-03

Posts: 75,004

Re: System unbootable after upgrade to linux-lts-6.12.58-1

https://wiki.archlinux.org/title/Genera … l_messages and only boot the multi-user.target (2nd link below) but my gut-feeling is  that you're booting and older kernel (forgot or failed to mount /boot or mounting a spurious /boot partition) and only restoring the previously used kernel fixes that by aligning booting an installed kernel (modules)?

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How to upload text · How to boot w/o GUI · Disable Windows Fast-Start! · Fix your xinitrc

gi1242

Member

Registered: 2022-07-07

Posts: 34

Re: System unbootable after upgrade to linux-lts-6.12.58-1

Thanks @seth. I enabled debugging messages; I'll see what it spits out when I'm able to upgrade + reboot it next.

After a bit of digging I suspect it's mounting the wrong root partition. I supply the `root=...` option correctly. However, the partition table has partition #2 with type 8404 (Linux root x86_64), and my actual root partition  with type 8400 (Generic Linux). So maybe that's causing a problem with the new kernels.

I'll post back Monday if I can either diagnose the problem, or solve it once debugging messges are enabled.

Thanks again.

seth

Member

From: Won't reply 2 private help req

Registered: 2012-09-03

Posts: 75,004

Re: System unbootable after upgrade to linux-lts-6.12.58-1

Don't reference the root partition via the device node (sda2, nvme0n1p2 etc) but use the UUID - the device node order isn't stable ie. sda and sdb can switch places any time.

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How to upload text · How to boot w/o GUI · Disable Windows Fast-Start! · Fix your xinitrc

gi1242

Member

Registered: 2022-07-07

Posts: 34

Re: System unbootable after upgrade to linux-lts-6.12.58-1

Thanks. I just did some digging. If I set the partition types correctly and include `systemd` in my mkinitcpio hooks, then I don't have to specify a `root=...` option, and I don't need entries in /etc/fstab.

I've lost count of how often I've messed up an install because I put the wrong UUID's in there. (It was a quick fix, but annoying).

I switched to this on my home computers, and it works great. (Now I don't even need to ensure I have good mount options; systemd seems to choose discard, relatime etc for me automatically). I'm going to run with this, and prey my work computer upgrades and boots Monday morning.

seth

Member

From: Won't reply 2 private help req

Registered: 2012-09-03

Posts: 75,004

Re: System unbootable after upgrade to linux-lts-6.12.58-1

prey my work computer

https://www.merriam-webster.com/dictionary/prey
https://www.merriam-webster.com/dictionary/pray

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How to upload text · How to boot w/o GUI · Disable Windows Fast-Start! · Fix your xinitrc

gi1242

Member

Registered: 2022-07-07

Posts: 34

Re: System unbootable after upgrade to linux-lts-6.12.58-1

Eye never did no how two spell. So sew me.