Intel IA-32 - Manual (Page 536)

14-10 Vol. 3A
MACHINE-CHECK ARCHITECTURE
When a machine-check error is detected on a Pentium 4 or Intel Xeon processor, the processor
saves the state of the general-purpose registers, the R/EFLAGS register, and the R/EIP in these
extended machine-check state MSRs. This information can be used by a debugger to analyze the
error.
These registers are read/write to zero registers. This means software can read them; but if soft-
ware writes to them, only all zeros is allowed. If software attempts to write a non-zero value into
one of these registers, a general-protection (#GP) exception is generated. These registers are
cleared on a hardware reset (power-up or RESET), but maintain their contents following a soft
reset (INIT reset).
IA32_MCG_RBP 186H Contains state of the RBP register at the time of the machine-check
error.
IA32_MCG_RSP 187H Contains state of the RSP register at the time of the machine-check
error.
IA32_MCG_RFLAGS 188H Contains state of the RFLAGS register at the time of the machine-
check error.
IA32_MCG_RIP 189H Contains state of the RIP register at the time of the machine-check
error.
IA32_MCG_MISC 18AH When set, indicates that a page assist or page fault occurred during
DS normal operation.
IA32_MCG_
RSERVED[1:5] 18BH-
18FH These registers, if present, are reserved.
IA32_MCG_R8 190H Contains state of the R8 register at the time of the machine-check
error.
IA32_MCG_R9 191H Contains state of the R9 register at the time of the machine-check
error.
IA32_MCG_R10 192H Contains state of the R10 register at the time of the machine-check
error.
IA32_MCG_R11 193H Contains state of the R11 register at the time of the machine-check
error.
IA32_MCG_R12 194H Contains state of the R12 register at the time of the machine-check
error.
IA32_MCG_R13 194H Contains state of the R8 register at the time of the machine-check
error.
IA32_MCG_R14 196H Contains state of the R14 register at the time of the machine-check
error.
IA32_MCG_R15 197H Contains state of the R15 register at the time of the machine-check
error.
Table 14-2. Extended Machine Check State MSRs
In Processors With Support For Intel EM64T (Contd.)
MSR Address Description