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I have been getting the following problem running Ubuntu 12.10. Basically, it freezes completely, doesn't respond to keyboard or mouse, CAPS won't change and alt+sys req+REISUB doesn't do anything. The problem is consistent in that after a hard reset it will be fine for a while but will freeze at some point. I've tried booting from a startup USB and this also froze so it isn't a OS problem, some hardware issue. Today I got the following messages before it froze. I guess what I want to find out is which hardware component is failing?

[Hardware Error]: CPU 0:  Machine Check Exception: 4 Bank 5: f200141014040400
[Hardware Error]: TSC Zc124d6Zdd
[Hardware Error]: PROCESSOR 0: 1067a TIME 1364221737 SOCKET 0 APIC 0 microcode a07
[Hardware Error]: Run the above through 'mcelog --ascii'
[Hardware Error]: CPU 1: Machine Check Exception: 5 Bank 0: f200084000000800
[Hardware Error]: RIP !INEXACT! 10:<ffffffff81031f8f> {mwait_idle_with_hints +0x5f/0x80}
[Hardware Error]: TSC Zc124d70df
[Hardware Error]: PROCESSOR 0: 1067a TIME 1364221737 SOCKET 0 APIC 1 microcode a07
[Hardware Error]: Run the above through 'mcelog --ascii'
[Hardware Error]: CPU 1: Machine Check Exception: 5 Bank 5: f2001410300c0400
[Hardware Error]: RIP !INEXACT! 10:<ffffffff81031f8f> {mwait_idle_with_hints +0x5f/0x80}
[Hardware Error]: TSC Zc124d70df
[Hardware Error]: Machine check: Processor context corrupt
Kernel Panic - not syncing: Fatal Machine check
panic occurred, switching back to text console
Rebooting in 30seconds ..


Also posted here: http://askubuntu.com/questions/272324/any-idea-what-type-of-error-this-is-machine-check-kernel-panic/

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migrated from stackoverflow.com Mar 25 '13 at 16:59

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What was the output when you ran the detected error though 'mcelog --ascii' ? –  Hennes Mar 25 '13 at 17:02
The "Intel 64 and IA32 architectures software developers manual -- volume 3B: system programming guide, part 2" has more detailed information in appendix E. It can be found at intel.co.uk/content/www/us/en/architecture-and-technology/… –  Hennes Mar 25 '13 at 23:27

2 Answers 2

Well, this kind of error seems well documented:

A Machine Check Exception (MCE) is a type of computer hardware error that  
occurs when a computer's central processing unit detects a hardware problem.
[...] On Linux, a process (such as klogd) writes a message to the kernel log 
and/or the console screen (usually only to the console when the error is 
non-recoverable and the machine crashes as a result).

The causes of this error are pretty vague, but the wikipedia page may help.

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To add up yo Don Juan dePython's answer, this link is an article that describes the potential causes behind a kernel panic. It refers to Mas OS, but they can pretty much be generalised. To sum them up:

  • Bad RAM / NVRAM
  • Bad USD device
  • Bad network connection
  • Bad built-in hardware including drives

And other, but all of the above have occasionaly occured to me in the past with Ubuntu or other OS's. You can start by recalling if something of the above has changed in your recent past, or by eliminating one-by-one factors with memtest, disconnecting devices etc.

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