739
Processor
May
Read
Branch
Status
Register
With
Inconsistent
Parity
Bit
Description
Under
a
highly
specific
and
detailed
set
of
internal
timing
conditions
,
the
processor
may
read
an
internal
branch
status
register
(
BSR
)
while
the
register
is
being
updated
and
may
observe
a
partially
written
entry
with
an
inconsistent
parity
bit
.
When
the
conditions
for
this
erratum
occur
,
the
processor
does
not
actually
use
the
contents
of
this
branch
status
register
,
however
it
may
report
a
parity
error
machine
check
exception
(#
MC
).
Potential
Effect
on
System
The
processor
reports
an
uncorrectable
machine
check
exception
for
a
branch
status
register
parity
error
.
MC
1_
STATUS
[
ErrorCodeExt
] (
MSR
0000_0405[20:16]) = 00110
b
identifies
a
branch
status
register
parity
error
.
Suggested
Workaround
BIOS
should
set
MSRC
001_0045[15] = 1
b
(
MC
1_
CTL
_
MASK
[
BSRP
]).
Fix
Planned
No
fix
planned
48063
Rev
. 3.18
October
2012
Revision
Guide
for
AMD
Family
15
h
Models
00
h-
0
Fh
Processors
Product
Errata
85