Specification Update

Errata
48 Specification Update
W37. CPUID Leaf 0x80000006 May Provide the Incorrect Value
for an 8-Way Associative Cache
Problem: CPUID leaf 0x80000006 may return 0x8 in ECX [15:12] to indicate 8-
way associative cache, but the correct encoding for an 8-way
associative cache is 0x6.
Implication: Software that depends on the associativity of the cache may not
function correctly.
Workaround: It is possible for the BIOS to contain a workaround for this erratum.
Status: For the steppings affected, see the Summary Tables of Changes.
W38. Snoops during the Execution of a HLT (Halt) Instruction
May Lead to Unexpected System Behavior
Problem: If during the execution of a HLT instruction an external snoop causes
an eviction from the instruction fetch unit (IFU) instruction cache, the
processor may, on exit from the HLT state, erroneously read stale data
from the victim cache.
Implication: This erratum may lead to unexpected system behavior. Intel has only
observed this condition in non-mobile configurations.
Workaround: It is possible for the BIOS to contain a workaround for this erratum.
Status: For the steppings affected, see the Summary Tables of Changes.
W39. Invalid Entries in Page-Directory-Pointer-Table Register
(PDPTR) May Cause General Protection (#GP) Exception
If the Reserved Bits Are Set to One
Problem: Invalid entries in the Page-Directory-Pointer-Table Register (PDPTR)
that have the reserved bits set to one may cause a General Protection
(#GP) exception.
Implication: Intel has not observed this erratum with any commercially-available
software.
Workaround: Do not set the reserved bits to one when PDPTR entries are invalid.
Status: For the steppings affected, see the Summary Tables of Changes.