soft lockup - cpu#0 stuck for n s

CPU soft lockup [ubuntu] - microcode 

If you're experiencing problems with soft lockup of you CPU this may be due to old BIOS firmware and incompatible CPU instruction set with your motherboard firmware. Motherboard manufacturers are reluctant to issue BIOS updates unless there is a major issue, so your CPU microcode can be quite dated. To fix this issue on Ubnutu (usually CPU lockups) there are intel and amd based microcode packages which are loaded without permanent BIOS changes on boot time.

For users owning intel processors you can install microcode like so:

sudo apt-get install intel-microcode microcode.ctl

For amd users:

sudo apt-get install amd64-microcode  

to check whether microcode has been loaded:

dmesg | grep microcode

for intel processors output should look something like this:

[    0.000000] CPU0 microcode updated early to revision 0x29, date = 2013-06-12
[    0.089933] CPU1 microcode updated early to revision 0x29, date = 2013-06-12
[    1.263975] microcode: CPU0 sig=0x206a7, pf=0x10, revision=0x29
[    1.263983] microcode: CPU1 sig=0x206a7, pf=0x10, revision=0x29
[    1.263991] microcode: CPU2 sig=0x206a7, pf=0x10, revision=0x29
[    1.263999] microcode: CPU3 sig=0x206a7, pf=0x10, revision=0x29
[    1.264074] microcode: Microcode Update Driver: v2.00 

<tigran@aivazian.fsnet.co.uk>, Peter Oruba


  

Note: Don't apply this fix unless you're experiencing CPU lockup problems. (If this does not correct your problem check out your CPU stability, check power supply as well.