Revert "x86: Side-step lguest problem by only building cmpxchg8b_emu for pre-Pentium"

This reverts commit ae1b22f6e4.

As Linus said in 982d007a6e: "There was something really messy about
cmpxchg8b and clone CPU's, so if you enable it on other CPUs later, do it
carefully."

This breaks lguest for those configs, but we can fix that by emulating
if we have to.

Fixes: http://bugzilla.kernel.org/show_bug.cgi?id=14884
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
LKML-Reference: <201001051248.49700.rusty@rustcorp.com.au>
Cc: stable@kernel.org
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
This commit is contained in:
Rusty Russell 2010-01-05 12:48:49 +10:30 committed by H. Peter Anvin
parent a557aae29c
commit f4b825bde9

View file

@ -396,7 +396,7 @@ config X86_TSC
config X86_CMPXCHG64
def_bool y
depends on !M386 && !M486
depends on X86_PAE || X86_64 || MCORE2 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MATOM
# this should be set for all -march=.. options where the compiler
# generates cmov.