[SOLVED] How do I restore my kernel from a live CD or USB boot?

bmdavll · 2009-10-12 06:32:26

Hi all,
I have a major problem with my system. I updated to the latest kernel (2.6.31) and tried to reboot.
However, now it gets stuck during the boot process. Specifically, right after the line

:: Waiting for UDev uevents to be processed

the display flashes and then everything freezes (even the cursor stops blinking). No luck with the fallback image either.
Since I can't boot at all, I think I need to restore my kernel to 2.6.30 from a USB image or live CD.

I have no clue how to fix this. Please help, thanks!

Edit: thanks hokasch and others. I used that method to restore my kernel to 2.6.30. This was a reported bug (http://bugs.archlinux.org/task/16575)

Last edited by bmdavll (2009-10-12 19:31:44)

quarkup · 2009-10-12 09:34:17

well on irc channel someone has appeared with the same issue - first of all (or last of all), submit a bug report.

you can boot from the liveCD or USBpen ..

then just login (as root) and then mount your archlinux partition somewhere (something like this)

# mount /dev/sdaX /mnt
# chroot /mnt /bin/bash

replace sdaX with your right partition (sda1, sda2, sda3, sda4 ... or maybe hda1, hda2.. - if the linux has been installed in a external drive its more likely to be hdb1 or hdb2).

actually if you don't really know the right device (partition) you will try each one until u find it.

then u are on your archlinux box.
configure the net (if you don't have it)

then you can downgrade/upgrade the packages.. or repair your box as u can.
maybe on IRC someone can give u a hint on that.

vacant · 2009-10-12 10:57:15

quarkup wrote:

if you don't really know the right device (partition) you will try each one until u find it.

"fdisk -l device" will list the partition table for "device" (e.g. fdisk -l /dev/sda) and show useful information like the size of the disk

sasquatch74 · 2009-10-12 14:05:24

Sorry to hear about your problems.
There is a wiki page on this topic here:
http://wiki.archlinux.org/index.php/Kernel_Panics
Hope it helps

hokasch · 2009-10-12 14:12:33

I just had to rebuild my initramfs after testing KMS and somehow messing up my mkinitcpio.conf in the process.
For downgrading your kernel, see the Downgrade Packages wiki page. Basically, if you did not clean your package cache, it should still be there ready to install.

So here is how to propely chroot into your install from a LiveCd (pulled from various other threads):

1. Boot from liveCD/usbimage
2. Set up your network if needed later
3. Prepare your Chroot:

# mkdir /mnt/arch                        #optional, you may also just use /mnt/
# mount /dev/sdax /mnt/arch              #substitute sdax with your root partition
# mount /dev/sday /mnt/arch/boot         #only needed if you have a seperate partition sday for /boot
# mount -t proc proc /mnt/arch/proc      #mount system folders
# mount -t sysfs sys /mnt/arch/sys
# mount -o bind /dev /mnt/arch/dev

4. Chroot into your Install

chroot /mnt/arch/

After that, you may downgrade/upgrade/split your screen with an axe, as you like.
To just rebuild the initramfs, type:

mkinitcpio -v -k <kernel version-ARCH> -g /boot/kernel26.img

EDIT: DAMN, too late... and it is all in the wiki!! I just spend half an hour scrolling through forum posts, figuring out why autodetection would not work (mount dev sys proc). Wiki awesomeness - wins again. To dump to find the wiki page - zero points for me.

Last edited by hokasch (2009-10-12 21:24:47)

Arch Linux

#1 2009-10-12 06:32:26

[SOLVED] How do I restore my kernel from a live CD or USB boot?

#2 2009-10-12 09:34:17

Re: [SOLVED] How do I restore my kernel from a live CD or USB boot?

#3 2009-10-12 10:57:15

Re: [SOLVED] How do I restore my kernel from a live CD or USB boot?

#4 2009-10-12 14:05:24

Re: [SOLVED] How do I restore my kernel from a live CD or USB boot?

#5 2009-10-12 14:12:33

Re: [SOLVED] How do I restore my kernel from a live CD or USB boot?

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