Table of Contents
Advertisement
Errata
AAK1.
MCi_Status Overflow Bit May Be Incorrectly Set on a Single Instance
of a DTLB Error
Problem:
A single Data Translation Look Aside Buffer (DTLB) error can incorrectly set the
Overflow (bit [62]) in the MCi_Status register. A DTLB error is indicated by MCA error
code (bits [15:0]) appearing as binary value, 000x 0000 0001 0100, in the MCi_Status
register.
Implication:
Due to this erratum, the Overflow bit in the MCi_Status register may not be an
accurate indication of multiple occurrences of DTLB errors. There is no other impact to
normal processor functionality.
Workaround:
None identified.
Status:
For the steppings affected, see the
AAK2.
Debug Exception Flags DR6.B0-B3 Flags May be Incorrect for Disabled
Breakpoints
Problem:
When a debug exception is signaled on a load that crosses cache lines with data
forwarded from a store and whose corresponding breakpoint enable flags are disabled
(DR7.G0-G3 and DR7.L0-L3), the DR6.B0-B3 flags may be incorrect.
Implication:
The debug exception DR6.B0-B3 flags may be incorrect for the load if the
corresponding breakpoint enable flag in DR7 is disabled.
Workaround:
None identified.
Status:
For the steppings affected, see the
AAK3.
MONITOR or CLFLUSH on the Local XAPIC's Address Space Results in
Hang
Problem:
If the target linear address range for a MONITOR or CLFLUSH is mapped to the local
xAPIC's address space, the processor will hang.
Implication:
When this erratum occurs, the processor will hang. The local xAPIC's address space
must be uncached. The MONITOR instruction only functions correctly if the specified
linear address range is of the type write-back. CLFLUSH flushes data from the cache.
Intel has not observed this erratum with any commercially available software.
Workaround:
Do not execute MONITOR or CLFLUSH instructions on the local xAPIC address space.
Status:
For the steppings affected, see the
AAK4.
Corruption of CS Segment Register During RSM While Transitioning
From Real Mode to Protected Mode
Problem:
During the transition from real mode to protected mode, if an SMI (System
Management Interrupt) occurs between the MOV to CR0 that sets PE (Protection
Enable, bit 0) and the first FAR JMP, the subsequent RSM (Resume from System
Management Mode) may cause the lower two bits of CS segment register to be
corrupted.
Implication:
The corruption of the bottom two bits of the CS segment register will have no impact
unless software explicitly examines the CS segment register between enabling
protected mode and the first FAR JMP. Intel® 64 and IA-32 Architectures Software
Developer's Manual Volume 3A: System Programming Guide, Part 1, in the section
titled "Switching to Protected Mode" recommends the FAR JMP immediately follows the
Intel® Xeon® Processor 5500 Series
Specification Update, February 2014
Summary Tables of
Changes.
Summary Tables of
Changes.
Summary Tables of
Changes.
21
Advertisement
Table of Contents
