1 files changed, 18 insertions, 23 deletions

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index d1ed34856412..bcfc0bc15153 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -102,7 +102,7 @@ EXPORT_SYMBOL_GPL(halt_poll_ns_shrink);
 DEFINE_MUTEX(kvm_lock);
 LIST_HEAD(vm_list);
 
-static cpumask_var_t cpus_hardware_enabled;
+static DEFINE_PER_CPU(bool, hardware_enabled);
 static int kvm_usage_count;
 static atomic_t hardware_enable_failed;
 
@@ -5096,21 +5096,17 @@ static struct miscdevice kvm_dev = {
 
 static void hardware_enable_nolock(void *junk)
 {
-	int cpu = smp_processor_id();
-	int r;
-
-	if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
+	if (__this_cpu_read(hardware_enabled))
 		return;
 
-	cpumask_set_cpu(cpu, cpus_hardware_enabled);
-
-	r = kvm_arch_hardware_enable();
-
-	if (r) {
-		cpumask_clear_cpu(cpu, cpus_hardware_enabled);
+	if (kvm_arch_hardware_enable()) {
 		atomic_inc(&hardware_enable_failed);
-		pr_info("kvm: enabling virtualization on CPU%d failed\n", cpu);
+		pr_info("kvm: enabling virtualization on CPU%d failed\n",
+			raw_smp_processor_id());
+		return;
 	}
+
+	__this_cpu_write(hardware_enabled, true);
 }
 
 static int kvm_online_cpu(unsigned int cpu)
@@ -5139,12 +5135,16 @@ static int kvm_online_cpu(unsigned int cpu)
 
 static void hardware_disable_nolock(void *junk)
 {
-	int cpu = smp_processor_id();
-
-	if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
+	/*
+	 * Note, hardware_disable_all_nolock() tells all online CPUs to disable
+	 * hardware, not just CPUs that successfully enabled hardware!
+	 */
+	if (!__this_cpu_read(hardware_enabled))
 		return;
-	cpumask_clear_cpu(cpu, cpus_hardware_enabled);
+
 	kvm_arch_hardware_disable();
+
+	__this_cpu_write(hardware_enabled, false);
 }
 
 static int kvm_offline_cpu(unsigned int cpu)
@@ -5945,13 +5945,11 @@ int kvm_init(unsigned vcpu_size, unsigned vcpu_align, struct module *module)
 	int r;
 	int cpu;
 
-	if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL))
-		return -ENOMEM;
-
 	r = cpuhp_setup_state_nocalls(CPUHP_AP_KVM_ONLINE, "kvm/cpu:online",
 				      kvm_online_cpu, kvm_offline_cpu);
 	if (r)
-		goto out_free_2;
+		return r;
+
 	register_reboot_notifier(&kvm_reboot_notifier);
 
 	/* A kmem cache lets us meet the alignment requirements of fx_save. */
@@ -6024,8 +6022,6 @@ out_free_4:
 out_free_3:
 	unregister_reboot_notifier(&kvm_reboot_notifier);
 	cpuhp_remove_state_nocalls(CPUHP_AP_KVM_ONLINE);
-out_free_2:
-	free_cpumask_var(cpus_hardware_enabled);
 	return r;
 }
 EXPORT_SYMBOL_GPL(kvm_init);
@@ -6051,7 +6047,6 @@ void kvm_exit(void)
 	unregister_reboot_notifier(&kvm_reboot_notifier);
 	cpuhp_remove_state_nocalls(CPUHP_AP_KVM_ONLINE);
 	kvm_irqfd_exit();
-	free_cpumask_var(cpus_hardware_enabled);
 }
 EXPORT_SYMBOL_GPL(kvm_exit);