x86/intel_rdt: Enable CMT and MBM on new Skylake stepping

BugLink: http://bugs.launchpad.net/bugs/1800537
commit 1d9f3e20a56d33e55748552aeec597f58542f92d upstream.

New stepping of Skylake has fixes for cache occupancy and memory
bandwidth monitoring.

Update the code to enable these by default on newer steppings.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: stable@vger.kernel.org # v4.14
Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Link: https://lkml.kernel.org/r/20180608160732.9842-1-tony.luck@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/arch/x86/kernel/cpu/intel_rdt.c b/arch/x86/kernel/cpu/intel_rdt.c
index af5fdcea67f63c1de3564015d0c43302e3ee122a..c979b2a1b3f69fe1538a48fd17363918acd13a43 100644 (file)
--- a/arch/x86/kernel/cpu/intel_rdt.c
+++ b/arch/x86/kernel/cpu/intel_rdt.c
@@ -775,6 +775,8 @@ static __init void rdt_quirks(void)
        case INTEL_FAM6_SKYLAKE_X:
                if (boot_cpu_data.x86_stepping <= 4)
                        set_rdt_options("!cmt,!mbmtotal,!mbmlocal,!l3cat");
+               else
+                       set_rdt_options("!l3cat");
        }
 }