--- zzzz-none-000/linux-3.10.107/arch/x86/oprofile/nmi_int.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/x86/oprofile/nmi_int.c	2021-02-04 17:41:59.000000000 +0000
@@ -64,11 +64,11 @@
 static int profile_exceptions_notify(unsigned int val, struct pt_regs *regs)
 {
 	if (ctr_running)
-		model->check_ctrs(regs, &__get_cpu_var(cpu_msrs));
+		model->check_ctrs(regs, this_cpu_ptr(&cpu_msrs));
 	else if (!nmi_enabled)
 		return NMI_DONE;
 	else
-		model->stop(&__get_cpu_var(cpu_msrs));
+		model->stop(this_cpu_ptr(&cpu_msrs));
 	return NMI_HANDLED;
 }
 
@@ -91,7 +91,7 @@
 
 static void nmi_cpu_start(void *dummy)
 {
-	struct op_msrs const *msrs = &__get_cpu_var(cpu_msrs);
+	struct op_msrs const *msrs = this_cpu_ptr(&cpu_msrs);
 	if (!msrs->controls)
 		WARN_ON_ONCE(1);
 	else
@@ -111,7 +111,7 @@
 
 static void nmi_cpu_stop(void *dummy)
 {
-	struct op_msrs const *msrs = &__get_cpu_var(cpu_msrs);
+	struct op_msrs const *msrs = this_cpu_ptr(&cpu_msrs);
 	if (!msrs->controls)
 		WARN_ON_ONCE(1);
 	else
@@ -403,7 +403,7 @@
 		nmi_cpu_shutdown(dummy);
 }
 
-static int nmi_create_files(struct super_block *sb, struct dentry *root)
+static int nmi_create_files(struct dentry *root)
 {
 	unsigned int i;
 
@@ -420,14 +420,14 @@
 			continue;
 
 		snprintf(buf,  sizeof(buf), "%d", i);
-		dir = oprofilefs_mkdir(sb, root, buf);
-		oprofilefs_create_ulong(sb, dir, "enabled", &counter_config[i].enabled);
-		oprofilefs_create_ulong(sb, dir, "event", &counter_config[i].event);
-		oprofilefs_create_ulong(sb, dir, "count", &counter_config[i].count);
-		oprofilefs_create_ulong(sb, dir, "unit_mask", &counter_config[i].unit_mask);
-		oprofilefs_create_ulong(sb, dir, "kernel", &counter_config[i].kernel);
-		oprofilefs_create_ulong(sb, dir, "user", &counter_config[i].user);
-		oprofilefs_create_ulong(sb, dir, "extra", &counter_config[i].extra);
+		dir = oprofilefs_mkdir(root, buf);
+		oprofilefs_create_ulong(dir, "enabled", &counter_config[i].enabled);
+		oprofilefs_create_ulong(dir, "event", &counter_config[i].event);
+		oprofilefs_create_ulong(dir, "count", &counter_config[i].count);
+		oprofilefs_create_ulong(dir, "unit_mask", &counter_config[i].unit_mask);
+		oprofilefs_create_ulong(dir, "kernel", &counter_config[i].kernel);
+		oprofilefs_create_ulong(dir, "user", &counter_config[i].user);
+		oprofilefs_create_ulong(dir, "extra", &counter_config[i].extra);
 	}
 
 	return 0;
@@ -494,14 +494,19 @@
 	if (err)
 		goto fail;
 
+	cpu_notifier_register_begin();
+
+	/* Use get/put_online_cpus() to protect 'nmi_enabled' */
 	get_online_cpus();
-	register_cpu_notifier(&oprofile_cpu_nb);
 	nmi_enabled = 1;
 	/* make nmi_enabled visible to the nmi handler: */
 	smp_mb();
 	on_each_cpu(nmi_cpu_setup, NULL, 1);
+	__register_cpu_notifier(&oprofile_cpu_nb);
 	put_online_cpus();
 
+	cpu_notifier_register_done();
+
 	return 0;
 fail:
 	free_msrs();
@@ -512,12 +517,18 @@
 {
 	struct op_msrs *msrs;
 
+	cpu_notifier_register_begin();
+
+	/* Use get/put_online_cpus() to protect 'nmi_enabled' & 'ctr_running' */
 	get_online_cpus();
-	unregister_cpu_notifier(&oprofile_cpu_nb);
 	on_each_cpu(nmi_cpu_shutdown, NULL, 1);
 	nmi_enabled = 0;
 	ctr_running = 0;
+	__unregister_cpu_notifier(&oprofile_cpu_nb);
 	put_online_cpus();
+
+	cpu_notifier_register_done();
+
 	/* make variables visible to the nmi handler: */
 	smp_mb();
 	unregister_nmi_handler(NMI_LOCAL, "oprofile");