Revert "x86, amd: Disable way access filter on Piledriver CPUs" it is duplicated

Revert 5e3fe67e02c53e5a5fcf0e2b0d91dd93f757d50b which is
commit 2bbf0a1427c377350f001fbc6260995334739ad7 upstream.

Willy pointed out that I messed up and applied this one twice to the
3.0-stable tree, so revert the second instance of it.

Reported by: Willy Tarreau <w@1wt.eu>
Cc: Andre Przywara <osp@andrep.de>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: CAI Qian <caiqian@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
reverted:

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index a93741d8de78ba00660c52019a38c7d464bf9d36..3f4b6dacf1c2633e7b0c18486f7a68b8e8bef25f 100644 (file)
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -568,20 +568,6 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
                }
        }
 
-       /*
-        * The way access filter has a performance penalty on some workloads.
-        * Disable it on the affected CPUs.
-        */
-       if ((c->x86 == 0x15) &&
-           (c->x86_model >= 0x02) && (c->x86_model < 0x20)) {
-               u64 val;
-
-               if (!rdmsrl_safe(0xc0011021, &val) && !(val & 0x1E)) {
-                       val |= 0x1E;
-                       checking_wrmsrl(0xc0011021, val);
-               }
-       }
-
        cpu_detect_cache_sizes(c);
 
        /* Multi core CPU? */