x86/intel_rdt: Do not allow pseudo-locking of MBA resource

rchatre · KAGA-KOKO · commit 32d736abed4f · 2018-09-18T23:38:06.000+02:00
A system supporting pseudo-locking may have MBA as well as CAT resources of which only the CAT resources could support cache pseudo-locking. When the schemata to be pseudo-locked is provided it should be checked that that schemata does not attempt to pseudo-lock a MBA resource. Fixes: e0bdfe8 ("x86/intel_rdt: Support creation/removal of pseudo-locked region") Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "H Peter Anvin" <hpa@zytor.com> Cc: "Tony Luck" <tony.luck@intel.com> Cc: "Xiaochen Shen" <xiaochen.shen@intel.com> Cc: "Chen Yu" <yu.c.chen@intel.com> Link: https://lkml.kernel.org/r/1537048707-76280-7-git-send-email-fenghua.yu@intel.com
diff --git a/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c b/arch/x86/kernel/cpu/intel_rdt_ctrlmondata.c
@@ -195,6 +195,12 @@ static int parse_line(char *line, struct rdt_resource *r,
 	struct rdt_domain *d;
 	unsigned long dom_id;
 
+	if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP &&
+	    r->rid == RDT_RESOURCE_MBA) {
+		rdt_last_cmd_puts("Cannot pseudo-lock MBA resource\n");
+		return -EINVAL;
+	}
+
 next:
 	if (!line || line[0] == '\0')
 		return 0;
