[tip:x86/urgent] x86/intel_rdt: Enable CMT and MBM on new Skylake stepping

[tip-bot for Tony Luck <tipbot@zytor.com>]

Commit-ID:  1d9f3e20a56d33e55748552aeec597f58542f92d
Gitweb:     https://git.kernel.org/tip/1d9f3e20a56d33e55748552aeec597f58542f92d
Author:     Tony Luck <tony.luck@intel.com>
AuthorDate: Fri, 8 Jun 2018 09:07:32 -0700
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Sat, 9 Jun 2018 16:04:34 +0200

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

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

---
 arch/x86/kernel/cpu/intel_rdt.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/x86/kernel/cpu/intel_rdt.c b/arch/x86/kernel/cpu/intel_rdt.c
index 589b948e6e01..316a8875bd90 100644
--- a/arch/x86/kernel/cpu/intel_rdt.c
+++ b/arch/x86/kernel/cpu/intel_rdt.c
@@ -821,6 +821,8 @@ 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");
 	}
 }