RE: PYXIS machine check

[kelvin qantel com]

Praveen Srinivasan wrote:

>So does this mean I need to replace my RAM?
>
>Praveen
>
>Greg Lindahl wrote:
>
>> > PYXIS Macine check: vector=0x660 pc=0xfffffc00003104a0 code=0x202
>>
>> The vector is the most important part of this, not the pc. According to
>> Jay's posting of 2 weeks ago, which should go into the FAQ:
>>
>> Machine checks are of four (4) types, as in the following table:
>>
>> Code      Reason                  Example or Common Cause
>> ====      ======                  =======================
>>
>> 620     System Correctable        correctable errors in the memory
subsystem,
>>                                   eg single bit ECC errors, detected
async to
>>                                   processor execution
>>
>> 630     Processor Correctable     correctable cache and TLB errors,
detected
>>                                   internally by the processor
>>
>> 660     System Uncorrectable      unrecoverable memory errors
>>
>> 670     Processor Uncorrectable   unrecoverable cache or TLB errors, or
>>                                   read of a non-existent I/O space
location
>>
>> This means that you're getting a double-bit error in your RAM. Jay
implies
>> that the errors are reported asynchronously, so the PC doesn't mean
>> anything...
>>
>> -- g

I think this is more likely a programming problem.  This error 
can be caused by accessing non-existent memory.  The pyxis chip
ECC checking is mainly done when non-processor accesses are 
occurring, such as PCI bus master DMA, and getting a double bit
error is very unlikely if you have not gotten any single bit
errors.  Other things which can cause it are PCI bus parity 
errors and PCI bus time-outs.

Kelvin