Arch Linux

ratcheer

Member

Registered: 2011-10-09

Posts: 912

[Solved] Cannot boot after kernel upgrade

Everything was fine on the 3.17.2 kernel. This morning's -Syu brought in kernel 3.17.3 along with package upgrades for dhcpcd and pacman-mirrorlist. I tried rebooting twice, both times with the same failure. I had to copy the console messages by hand, because the failure leaves me at an emergency prompt.

BTRFS: open_ctree failed
mount: wrong fs type, bad option, bad superblock on /dev/sdb2, missing codepage or helper program, or other error

In some cases useful info is found in syslog - try dmesg|tail or so.

You are now being dropped into an emergency shell.

Everything I can see from the dmesg|tail command are releted to USB devices, not /dev/sdb2. I tried to do dmesg|less, but less is apparently not available.

I will also try to research the problem through the btrfs resources.

Tim

Last edited by ratcheer (2014-11-17 19:19:03)

WorMzy

Administrator

From: Scotland

Registered: 2010-06-16

Posts: 12,400

Website

Re: [Solved] Cannot boot after kernel upgrade

Is this a btrfs RAID root?

From the prompt, try running the following:

modprobe btrfs
udevadm trigger

Then try to mount your root partition (remember to use '-o subvol=blahblahblah' if necessary. Then exit the emergency shell. If it works, add btrfs to your mkinitcpio.conf's MODULES array and rebuild your initramfs.

There should be a bug report about this somewhere.

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Sakura:-
Mobo: MSI MAG X570S TORPEDO MAX // Processor: AMD Ryzen 9 5950X @4.9GHz // GFX: AMD Radeon RX 5700 XT // RAM: 32GB (4x 8GB) Corsair DDR4 (@ 3000MHz) // Storage: 1x 3TB HDD, 6x 1TB SSD, 2x 120GB SSD, 1x 275GB M2 SSD

Making lemonade from lemons since 2015.

ratcheer

Member

Registered: 2011-10-09

Posts: 912

Re: [Solved] Cannot boot after kernel upgrade

Yes, it is / on btrfs RAID, but on a partition, not a subvol. Thanks for the suggestions. Trying...

Tim

ratcheer

Member

Registered: 2011-10-09

Posts: 912

Re: [Solved] Cannot boot after kernel upgrade

@WorMzy - Those commands succeeded, but I don't know what to do next to proceed from the emergency shell to a working system. I am still left at the BusyBox prompt.

Thanks.

gehidore

IRC Op

From: Near the pine trees

Registered: 2012-11-09

Posts: 35

Re: [Solved] Cannot boot after kernel upgrade

@WorMzy - Those commands succeeded, but I don't know what to do next to proceed from the emergency shell to a working system. I am still left at the BusyBox prompt.

Thanks.

Get back on the IRC...

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Windows get broken, penguins rarely get sucked into jet engines.

ratcheer

Member

Registered: 2011-10-09

Posts: 912

Re: [Solved] Cannot boot after kernel upgrade

Resolution:

1) Boot to Debian
2) chroot to Arch
3) Edit /etc/mkinitcpio.conf, adding btrfs to the MODULES list
4) mkinitcpio -p linux
5) Reboot to Arch

Ref: https://bbs.archlinux.org/viewtopic.php?id=189845

Tim

WorMzy

Administrator

From: Scotland

Registered: 2010-06-16

Posts: 12,400

Website

Re: [Solved] Cannot boot after kernel upgrade

@WorMzy - Those commands succeeded, but I don't know what to do next to proceed from the emergency shell to a working system. I am still left at the BusyBox prompt.

Thanks.

I should have clarified here, you should mount your root partition to new_root, then exit the busybox shell (by typing exit, or pressing Ctrl+D). All things being well, the boot process will continue where it left off and you'll end up in your Arch install as though nothing had happened.

Then you can make the changes you need to mkinitcpio.conf and regenerate your initramfs without needing a liveCD.

---

Sakura:-
Mobo: MSI MAG X570S TORPEDO MAX // Processor: AMD Ryzen 9 5950X @4.9GHz // GFX: AMD Radeon RX 5700 XT // RAM: 32GB (4x 8GB) Corsair DDR4 (@ 3000MHz) // Storage: 1x 3TB HDD, 6x 1TB SSD, 2x 120GB SSD, 1x 275GB M2 SSD

Making lemonade from lemons since 2015.

Lurkos

Member

Registered: 2014-02-12

Posts: 2

Re: [Solved] Cannot boot after kernel upgrade

Works also here.
I've wasted 1 complete day of work trying to fix this issue, because the error shown suggests a problem with the file system! :-/
The error shown, in fact, points to problems regarding the c_tree stuff, and not to the more simple unavailability of the proper kernel module.
How can we inform the maintainers of the website that a news about this issue should be written to prevent others to experience this?

rpodgorny

Member

Registered: 2014-11-19

Posts: 7

Re: [Solved] Cannot boot after kernel upgrade

me too. a day worth of work finally brought me here. please make an official announcement. thank you...

Spider.007

Member

Registered: 2004-06-20

Posts: 1,175

Re: [Solved] Cannot boot after kernel upgrade

Yeah; same for me; took me a few hours :X I'm not sure what causes this though? Is it a bug in the initcpio or the kernel?

davidm

Member

Registered: 2009-04-25

Posts: 371

Re: [Solved] Cannot boot after kernel upgrade

Works also here.
I've wasted 1 complete day of work trying to fix this issue, because the error shown suggests a problem with the file system! :-/
The error shown, in fact, points to problems regarding the c_tree stuff, and not to the more simple unavailability of the proper kernel module.
How can we inform the maintainers of the website that a news about this issue should be written to prevent others to experience this?

I'm not sure why they decided not to make an announcement.  I had the same sort of worry.  I also wonder how many people ended up trashing their btrfs filesystem trying to "fix" it with various attempts at filesystem repair.  I'll see maybe about editing the btrfs wiki entry and making a note in the Troubleshooting section at least.

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Why I support GNU/Linux

rpodgorny

Member

Registered: 2014-11-19

Posts: 7

Re: [Solved] Cannot boot after kernel upgrade

...so, i've created a bug report: https://bugs.archlinux.org/task/42884