From 48515970a05a66990a896611f414d0fec62b72e0 Mon Sep 17 00:00:00 2001
From: Balazs Gerofi <bgerofi@riken.jp>
Date: Mon, 19 Feb 2018 11:10:34 +0900
Subject: [PATCH] ihk_mc_get_processor_id(): return -1 for non-McKernel CPUs

Cherry-pick of c45641e97add9fde467844d9272f2626cf4317de
---
 arch/x86_64/kernel/local.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/x86_64/kernel/local.c b/arch/x86_64/kernel/local.c
index 84262fc9..3ca416d9 100644
--- a/arch/x86_64/kernel/local.c
+++ b/arch/x86_64/kernel/local.c
@@ -107,9 +107,17 @@ void init_boot_processor_local(void)
   @ ensures \result == %gs;
   @ assigns \nothing;
   */
+extern int num_processors;
 int ihk_mc_get_processor_id(void)
 {
 	int id;
+	void *gs;
+
+	gs = (void *)rdmsr(MSR_GS_BASE);
+	if (gs < (void *)locals ||
+			gs > ((void *)locals + LOCALS_SPAN * num_processors)) {
+		return -1;
+	}
 
 	asm volatile("movl %%gs:0, %0" : "=r"(id));