Unix & Linux Stack Exchange is a question and answer site for users of Linux, FreeBSD and other Un*x-like operating systems. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I wanted to upgrade the Linux kernel on my Debian wheezy (stable) on Thinkpad T60. I installed linux-image-3.2.0-0.bpo.4-686-pae, version 3.2.41-2~bpo60+1. The problem is it hangs during boot, just after Cleaning ifupdown.... with

BUG: soft lockup - CPU#1 stuck for 23s

Is there anything I can do about it, or is it a kernel bug? I've never experienced this problem with older 2.6.x kernels.

enter image description here

share|improve this question
Not really an expert or anything, but have you tried removing the "quiet" kernel boot parameter to get more verbose output? – Joseph R. May 21 '13 at 1:35
Is there a newer kernel package available for it? Most recent long term support kernel is 3.4.46. – Keith May 21 '13 at 6:12
up vote 4 down vote accepted

The key to what's happening is that it hung in modprobe: it's probably hung trying to load a module for a piece of hardware.

Stuff to try:

  • add noapic to the kernel command line, and make sure quiet isn't present so you can see what's going on
  • make sure your laptop's BIOS is at the latest version
  • if you do manage to figure out which module is causing the hang, boot from a recovery CD and add modules to /etc/modprobe.d/blacklist.conf
share|improve this answer
Seems that the problem was caused by module lirc_sir. After removing it, the kernel boots. Thanks. – Petr Pudlák May 21 '13 at 17:05

Potential issue #1

I found an issue similar to yours covered over in this Server Fault Q&A titled: How to fix “BUG: soft lockup - CPU#0 stuck for 17163091968s”?. Perhaps it's related to your issue as well.

Potential issue #2

Another issue in launchpad, sounds similar to yours. Issue's title: BUG: soft lockup - CPU#0 stuck for 23s! [kworker/0:3:566]; RIP: 0010:[] [] mei_timer+0xc3/0x260 [mei]. The workaround for this issue was to update to a newer kernel.


In general I would advise you to try upgrading to a newer kernel for starters only to confirm that the issue is with your combination of hardware + kernel version.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.