KVM: x86: missing locking in PIT/IRQCHIP/SET_BSP_CPU ioctl paths

Correct missing locking in a few places in x86's vm_ioctl handling path.

Signed-off-by: Marcelo Tosatti <[email protected]>
Signed-off-by: Avi Kivity <[email protected]>

Author: matosatti

arch/x86/kvm/i8254.c

@@ -345,9 +345,7 @@ static void pit_load_count(struct kvm *kvm, int channel, u32 val)
 
 void kvm_pit_load_count(struct kvm *kvm, int channel, u32 val)
 {
-	mutex_lock(&kvm->arch.vpit->pit_state.lock);
 	pit_load_count(kvm, channel, val);
-	mutex_unlock(&kvm->arch.vpit->pit_state.lock);
 }
 
 static inline struct kvm_pit *dev_to_pit(struct kvm_io_device *dev)

arch/x86/kvm/x86.c

@@ -1987,19 +1987,25 @@ static int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
 	r = 0;
 	switch (chip->chip_id) {
 	case KVM_IRQCHIP_PIC_MASTER:
+		spin_lock(&pic_irqchip(kvm)->lock);
 		memcpy(&pic_irqchip(kvm)->pics[0],
 			&chip->chip.pic,
 			sizeof(struct kvm_pic_state));
+		spin_unlock(&pic_irqchip(kvm)->lock);
 		break;
 	case KVM_IRQCHIP_PIC_SLAVE:
+		spin_lock(&pic_irqchip(kvm)->lock);
 		memcpy(&pic_irqchip(kvm)->pics[1],
 			&chip->chip.pic,
 			sizeof(struct kvm_pic_state));
+		spin_unlock(&pic_irqchip(kvm)->lock);
 		break;
 	case KVM_IRQCHIP_IOAPIC:
+		mutex_lock(&kvm->irq_lock);
 		memcpy(ioapic_irqchip(kvm),
 			&chip->chip.ioapic,
 			sizeof(struct kvm_ioapic_state));
+		mutex_unlock(&kvm->irq_lock);
 		break;
 	default:
 		r = -EINVAL;
@@ -2013,16 +2019,20 @@ static int kvm_vm_ioctl_get_pit(struct kvm *kvm, struct kvm_pit_state *ps)
 {
 	int r = 0;
 
+	mutex_lock(&kvm->arch.vpit->pit_state.lock);
 	memcpy(ps, &kvm->arch.vpit->pit_state, sizeof(struct kvm_pit_state));
+	mutex_unlock(&kvm->arch.vpit->pit_state.lock);
 	return r;
 }
 
 static int kvm_vm_ioctl_set_pit(struct kvm *kvm, struct kvm_pit_state *ps)
 {
 	int r = 0;
 
+	mutex_lock(&kvm->arch.vpit->pit_state.lock);
 	memcpy(&kvm->arch.vpit->pit_state, ps, sizeof(struct kvm_pit_state));
 	kvm_pit_load_count(kvm, 0, ps->channels[0].count);
+	mutex_unlock(&kvm->arch.vpit->pit_state.lock);
 	return r;
 }
 
@@ -2031,7 +2041,9 @@ static int kvm_vm_ioctl_reinject(struct kvm *kvm,
 {
 	if (!kvm->arch.vpit)
 		return -ENXIO;
+	mutex_lock(&kvm->arch.vpit->pit_state.lock);
 	kvm->arch.vpit->pit_state.pit_timer.reinject = control->pit_reinject;
+	mutex_unlock(&kvm->arch.vpit->pit_state.lock);
 	return 0;
 }
 

virt/kvm/kvm_main.c

@@ -2274,10 +2274,12 @@ static long kvm_vm_ioctl(struct file *filp,
 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
 	case KVM_SET_BOOT_CPU_ID:
 		r = 0;
+		mutex_lock(&kvm->lock);
 		if (atomic_read(&kvm->online_vcpus) != 0)
 			r = -EBUSY;
 		else
 			kvm->bsp_vcpu_id = arg;
+		mutex_unlock(&kvm->lock);
 		break;
 #endif
 	default: