Vol. 3B 16-1

CHAPTER 16

INTERPRETING MACHINE-CHECK

ERROR CODES

Encoding of the model-specific and other information fields is different across processor families. The differences 
are documented in the following sections.

16.1 

INCREMENTAL DECODING INFORMATION: PROCESSOR FAMILY 06H 

MACHINE ERROR CODES FOR MACHINE CHECK

Section 16.1 provides information for interpreting additional model-specific fields for external bus errors relating to 
processor family 06H. The references to processor family 06H refers to only IA-32 processors with CPUID signa-
tures listed in Table 16-1. 

These errors are reported in the IA32_MCi_STATUS MSRs. They are reported architecturally as compound errors 
with a general form of 0000 1PPT RRRR IILL in the MCA error code field. See Chapter 15 for information on the 
interpretation of compound error codes. Incremental decoding information is listed in Table 16-2.

Table 16-1.   CPUID DisplayFamily_DisplayModel Signatures for Processor Family 06H

DisplayFamily_DisplayModel

Processor Families/Processor Number Series

06_0EH

Intel Core Duo, Intel Core Solo processors

06_0DH

Intel Pentium M processor

06_09H

Intel Pentium M processor

06_7H, 06_08H, 06_0AH, 06_0BH

Intel Pentium III Xeon Processor, Intel Pentium III Processor

06_03H, 06_05H

Intel Pentium II Xeon Processor, Intel Pentium II Processor 

06_01H

Intel Pentium Pro Processor 

Table 16-2.  Incremental Decoding Information: Processor Family 06H Machine Error Codes For Machine Check

Type

Bit No.  Bit Function 

Bit Description

MCA error 

codes

1

 

0-15

Model specific 

errors

16-18

Reserved

Reserved

Model specific 

errors

19-24  Bus queue request 

type

000000 for BQ_DCU_READ_TYPE error
000010 for BQ_IFU_DEMAND_TYPE error
000011 for BQ_IFU_DEMAND_NC_TYPE error
000100 for BQ_DCU_RFO_TYPE error
000101 for BQ_DCU_RFO_LOCK_TYPE error
000110 for BQ_DCU_ITOM_TYPE error
001000 for BQ_DCU_WB_TYPE error
001010 for BQ_DCU_WCEVICT_TYPE error
001011 for BQ_DCU_WCLINE_TYPE error
001100 for BQ_DCU_BTM_TYPE error