Re: bluesmoke, machine check exception, reboot

[Randy.Dunlap]

On Tue, 28 May 2002, Corin Hartland-Swann wrote:

| Alan,
|
| On 28 May 2002, Alan Cox wrote:
| > On Tue, 2002-05-28 at 13:19, Corin Hartland-Swann wrote:
| > > I have a Dual PIII-1000 running 2.4.18, and am occasionally getting the
| > > following error:
| > >
| > > > CPU 1: Machine Check Exception: 0000000000000004
| > > > Bank 1: f200000000000115
| > > > Kernel panic: CPU context corrupt
|
| I just found another set of messages in the logs as well:
|
| CPU 1: Machine Check Exception: 0000000000000004
| Bank 1: b200000000000115
| Kernel panic: CPU context corrupt
|
| > > This results in a hard lock (unable to use magic SysRQ key to sync or
| > > reboot, etc). I located these errors in arch/i386/kernel/bluesmoke.c in
| > > the function intel_machine_check(). From what I have read on lkml it is
| > > probably a result of the processor overheating and causing errors.
| >
| > It may even be a faulty processor. If you are running the processor to
| > spec and your heatsink/fan/voltage all check out you may want to see
| > about getting the CPU replaced. Thats a data cache l1 read error it
| > appears
|
| How do you work out what the numbers mean? Is there some kind of reference
| to it, or are you just Alan "decodes machine check exceptions in his head"
| Cox :) From the code it seems to be some kind of MCG status and MC0 status
| - but of course, I have no idea what that means...

Appendix E of
"IA-32 Intel Architecture Software Developer's Manual
Volume 3 : System Programming Guide" is
"INTERPRETING MACHINE-CHECK ERROR CODES".
You can download it from developer.intel.com website.

Dave Jones has also begun a program called "parsemce".
You can get it at
http://www.codemonkey.org.uk/cruft/parsemce.c and
compile/run it.

| > That /proc setting should cause a reboot although after an MCE all
| > things are a little undefined
|
| After checking the logs (above) I found that the two times this has
| happened it has managed to write it to the logs. Is the fact that it
| sync()d a good indication that it will manage to reboot OK?
|
| Thanks,
| Corin

-- 
~Randy