Intel E6600 - Core 2 Duo Dual-Core Processor Specification page 50

instruction address by the LBR (Last Branch Record) branch-from instruction
address.
Implication: A BTM/BTS branch-from instruction address may get corrupted for software
interrupts.
Workaround: None identified.
For the steppings affected, see the Summary Tables of Changes.
Status:
AI78. Last Branch Records (LBR) Updates May be Incorrect After a Task
Switch
A Task-State Segment (TSS) task switch may incorrectly set the LBR_FROM
Problem:
value to the LBR_TO value.
Implication: The LBR_FROM will have the incorrect address of the Branch Instruction.
Workaround: None identified.
For the steppings affected, see the Summary Tables of Changes.
Status:
AI79. REP Store Instructions in a Specific Situation may cause the
Processor to Hang
During a series of REP (repeat) store instructions a store may try to dispatch
Problem:
to memory prior to the actual completion of the instruction. This behavior
depends on the execution order of the instructions, the timing of a
speculative jump and the timing of an uncacheable memory store. All types
of REP store instructions are affected by this erratum.
Implication: When this erratum occurs, the processor may live lock and/or result in a
system hang.
Workaround: It is possible for BIOS to contain a workaround for this erratum.
For the steppings affected, see the Summary Tables of Changes.
Status:
AI80. Performance Monitoring Events for L1 and L2 Miss May Not be
Accurate
Performance monitoring events 0CBh with an event mask value of 02h or 08h
Problem:
(MEM_LOAD_RETIRED.L1_LINE_MISS or
MEM_LOAD_RETIRED.L2_LINE_MISS) may under count the cache miss
events.
Implication: Performance monitoring events 0CBh with an event mask value of 02h or 08h
may show a count which is lower than expected; the amount by which the
count is lower is dependent on other conditions occurring on the same load
that missed the cache.
Workaround: None Identified.
For the steppings affected, see the Summary Tables of Changes.
Status:
50 Intel
®
Intel Core™2 Duo Desktop Processor E6000 and E4000 Sequence
®
Core™2 Extreme Processor X6800 and
Specification Update
Errata