i7-3612QE Kernel Panic and shut down

[EOffe]

I have an i7-3612Qe system that has been giving kernel panics when running a certain application pretty consistently after a couple minutes. After the kernel panic, the machine reboots. When I turn off turbo mode in the BIOS, the panics happen less frequently. Other BIOS settings are all default, no overclocking or anything fancy.

-Can be reproduced by running streaming application using ~250% CPU, temps are a little high, they float around 68-71 degrees

-sysbench runs fine with 8 threads, throttles CPU up to ~800%, no kernel panics, temps remain below 70 degrees

-MemTest did not report any errors

-Intel Processor Diagnotic tool passed

-Tried swapping RAM

-Happens on all of our machines, not just a single processor (possibly eliminates it being a bad single proc)

-Able to mitigate most of the kernel panics and reboots by disabling Turbo mode (this is unacceptable, just including this for debugging purposes)

-Also able to mitigate kernel panics and reboots by changing the cpu frequency sacling_governor to conservative, from ondemand. Conservative should "gracefully increase and decreases the CPU speed

rather than jumping to max speed the moment there is any load on the CPU" (https://www.kernel.org/doc/Documentation/cpu-freq/governors.txt https://www.kernel.org/doc/Documentation/cpu-freq/governors.txt)

Here is what I could copy down from the kernel panic on the monitor, sometimes the messages vary slightly, bu the TSC and PROCESSOR messages are almost always the same.

[Hardware Error]: TSC 6e496d96062

[Hardware Error]: PROCESSOR 0:306a9 TIME 1418929330 SOCKET 0 APIC 3 microcode 12

[Hardware Error]: Run the above through 'mcelog --ascii'

[Hardware Error]: CPU 0: Machine Check Exception: 5 Bank 4: b200000000100402

[Hardware Error]: RIP !INEXACT! 10: {intel_idle+0xb9/0x119}

[Hardware Error]: TSC 148c99828a0

[Hardware Error]: PROCESSOR 0:306a9 TIME 1418929330 SOCKET 0 APIC 3 microcode 12

[Hardware Error]: Run the above through 'mcelog --ascii'

[Hardware Error]: Some CPUs didn't answer in synchronization

[Hardware Error]: Machine check: Processor context corrupt

Kernel panic - not synching: Fatal machine check on current CPU

Pid: 0, comm: swapper/3 Tained: P M 0 3.2.0-4-amd64 # 1 Debian 3.2.51-1

Call Trace: ...

Also, here is a post from superuser on some suggestions that I tried: http://superuser.com/questions/854199/kernel-panic-from-overheating?noredirect=1# comment1130272_854199 cpu - Kernel Panic from overheating? - Super User

Any ideas for what to try next?

[Kevin_M_Intel]

Hello ejo4041,

May I know what applications are you running when issue appears? What Linux Distro are you using?

Kevin M

[EOffe]

The application is FFmpeg. The Linux Distro is Debian 3.2.51-1.

[EOffe]

Kernel: 3.2.0-4-amd64 # 1 SMP Debian 3.2.51-1 x86_64 GNU/Linux

Debian Version: 7.2

[EOffe]

Here is a screen shot of a kernel panic that just happened while the machine was idle.

[Kevin_M_Intel]

Thank you for sharing this information.

M recommendation is to post your query on Debian community so other users can provide their experience on commands.

Here is the link:

https://www.debian.org/support https://www.debian.org/support

Kevin m