LoongArch: KVM: Add missing slots_lock for device register/unregister

commit aeded60 upstream.

kvm_io_bus_register_dev() and kvm_io_bus_unregister_dev() should be
called under kvm->slots_lock. The unregister calls in ipi.c, eiointc.c
and pch_pic.c were also missing this protection. Add it to match the
register side.

Cc: stable@vger.kernel.org
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Zeng Chi <zengchi@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Zeng Chi

arch/loongarch/kvm/intc/eiointc.c

@@ -654,10 +654,14 @@ static int kvm_eiointc_create(struct kvm_device *dev, u32 type)
 
 	device = &s->device_vext;
 	kvm_iodevice_init(device, &kvm_eiointc_virt_ops);
+	mutex_lock(&kvm->slots_lock);
 	ret = kvm_io_bus_register_dev(kvm, KVM_IOCSR_BUS,
 			EIOINTC_VIRT_BASE, EIOINTC_VIRT_SIZE, device);
+	mutex_unlock(&kvm->slots_lock);
 	if (ret < 0) {
+		mutex_lock(&kvm->slots_lock);
 		kvm_io_bus_unregister_dev(kvm, KVM_IOCSR_BUS, &s->device);
+		mutex_unlock(&kvm->slots_lock);
 		kfree(s);
 		return ret;
 	}
@@ -676,8 +680,10 @@ static void kvm_eiointc_destroy(struct kvm_device *dev)
 
 	kvm = dev->kvm;
 	eiointc = kvm->arch.eiointc;
+	mutex_lock(&kvm->slots_lock);
 	kvm_io_bus_unregister_dev(kvm, KVM_IOCSR_BUS, &eiointc->device);
 	kvm_io_bus_unregister_dev(kvm, KVM_IOCSR_BUS, &eiointc->device_vext);
+	mutex_unlock(&kvm->slots_lock);
 	kfree(eiointc);
 	kfree(dev);
 }

arch/loongarch/kvm/intc/ipi.c

@@ -457,7 +457,9 @@ static void kvm_ipi_destroy(struct kvm_device *dev)
 
 	kvm = dev->kvm;
 	ipi = kvm->arch.ipi;
+	mutex_lock(&kvm->slots_lock);
 	kvm_io_bus_unregister_dev(kvm, KVM_IOCSR_BUS, &ipi->device);
+	mutex_unlock(&kvm->slots_lock);
 	kfree(ipi);
 	kfree(dev);
 }

arch/loongarch/kvm/intc/pch_pic.c

@@ -473,7 +473,9 @@ static void kvm_pch_pic_destroy(struct kvm_device *dev)
 	kvm = dev->kvm;
 	s = kvm->arch.pch_pic;
 	/* unregister pch pic device and free it's memory */
+	mutex_lock(&kvm->slots_lock);
 	kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS, &s->device);
+	mutex_unlock(&kvm->slots_lock);
 	kfree(s);
 	kfree(dev);
 }