eXTReMe Tracker
Dec 062011
 

The newer releases of Ubuntu and Linux Mint have started getting stuck during LiveCD installation or after distribution/kernel upgrade.  Usually the point where it gets stagnant is when it reaches this line:

kernel_thread_helper+0x7/0x10

Nothing happens past that point. A solution or a workaround to this is to insert the nolapic acpi=off switch in the grub boot line. There are 3 ways to do this:

1: If you are starting a fresh install from a CD and the installation pauses at the kernel_thread_helper line, you need to restart your computer.

When you boot from your installation CD, choose F6 before you continue trying out the LiveCD. This give you boot option at the bottom of your screen.

At the very end of the line add nolapic acpi=off and hit enter to continue booting from LiveCD. In most cases this should work.

2. The same problem may arise when you do a distribution upgrade or even a kernel upgrade. In that case you need to change your grub.cfg file. Follow these steps:

sudo nano /boot/grub/grub.cfg

Enter your sudo password and it will bring you to your grub menu configuration.

Look for the section that read similar to this:

menuentry 'Ubuntu, with Linux 2.6.38-11-generic' --class ubuntu --class gnu-linux --class gnu --class os {
 recordfail
 set gfxpayload=$linux_gfx_mode
 insmod part_msdos
 insmod ext2
 set root='(hd0,msdos6)'
 search --no-floppy --fs-uuid --set=root 337e2841-fc82-61b3-84be-5a9c71ae43b8
  linux   /boot/vmlinuz-2.6.38-11-generic root=UUID=337e2841-fc82-61b3-84be-5a9c71ae43b8 ro quiet splash vt.handoff=7
 initrd  /boot/initrd.img-2.6.38-11-generic
 }

You want to change the line that I have identified above to read:

linux   /boot/vmlinuz-2.6.38-11-generic root=UUID=337e2841-fc82-61b3-84be-5a9c71ae43b8 ro quiet splash vt.handoff=7 nolapic acpi=off

After adding these switches to the boot menu option, press ctrl-X, then save and exit.

This is for a permanent change if you can boot using an older kernel.

3: If you cannot login to an older kernel or recovery mode because of the kernel_thread_helper error,  you have to press “e” (without the quotation marks)  to edit the boot options when you get the grub menu.

For the kernel you want to use, edit the end of the line that reads

linux   /boot/vmlinuz-2.6.38-11-generic root=UUID=337e2841-fc82-61b3-84be-5a9c71ae43b8 ro quiet splash vt.handoff=7

to

linux   /boot/vmlinuz-2.6.38-11-generic root=UUID=337e2841-fc82-61b3-84be-5a9c71ae43b8 ro quiet splash vt.handoff=7 nolapic acpi=off

Press Enter and you should be able to boot.