Specification Update
31
BJ51.
Conflict Between Processor Graphics Internal Message Cycles And
Graphics Reads From Certain Physical Memory Ranges May Cause a
System Hang
Problem:
Processor Graphics internal message cycles occurring concurrently with a physical
memory read by graphics from certain memory ranges may cause memory reads to be
stalled resulting in a system hang. The following physical page (4K) addresses cannot
be assigned to Processor Graphics: 00_2005_0xxx, 00_2013_0xxx, 00_2013_8xxx and
00_4000_4xxx.
Implication:
Due to this erratum, accesses by the graphics engine to the defined memory ranges
may cause memory reads to be stalled, resulting in a system hang.
Workaround:
Workaround:
A BIOS code change has been identified and may be implemented as a workaround for
this erratum.
Status:
For the steppings affected, see the Summary Tables of Changes.
BJ52.
Execution of Opcode 9BH with the VEX Opcode Extension May Produce
a #NM Exception
Problem:
Attempt to use opcode 9BH with a VEX opcode extension should produce a #UD
(Invalid-Opcode) exception. Due to this erratum, if CR0.MP and CR0.TS are both 1, the
processor may produce a #NM (Device-Not-Available) exception if one of the following
conditions exists:
•
66H, F2H, F3H or REX as a preceding prefix;
•
An illegal map specified in the VEX.mmmmm field;
Implication:
Due to this erratum, some undefined instruction encodings may produce a #NM instead
of a #UD exception.
Workaround:
Software should not use opcode 9BH with the VEX opcode extension.
Status:
For the steppings affected, see the Summary Tables of Changes.
BJ53.
Executing The GETSEC Instruction While Throttling May Result in a
Processor Hang
Problem:
If the processor throttles due to either high temperature thermal conditions or due to
an explicit operating system throttling request (TT1) while executing GETSEC[SENTER]
or GETSEC[SEXIT] instructions, then under certain circumstances, the processor may
hang. Intel has not been observed this erratum with any commercially available
software.
Implication:
Possible hang during execution of GETSEC instruction.
Workaround:
None identified.
Status:
For the steppings affected, see the Summary Tables of Changes.
