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

commit 1d9f3e2 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 <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: Fenghua Yu <[email protected]>
Cc: [email protected] # v4.14
Cc: Vikas Shivappa <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: aegl

arch/x86/kernel/cpu/intel_rdt.c

@@ -773,6 +773,8 @@ 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");
 	}
 }