virtio: Protect vqs list access

VQs may be accessed to mark the device broken while they are
created/destroyed. Hence protect the access to the vqs list.

Fixes: e2dcdfe95c ("virtio: virtio_break_device() to mark all virtqueues broken.")
Signed-off-by: Parav Pandit <parav@nvidia.com>
Link: https://lore.kernel.org/r/20210721142648.1525924-4-parav@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Parav Pandit 2021-07-21 17:26:47 +03:00 committed by Michael S. Tsirkin
parent 249f255476
commit 0e566c8f0f
3 changed files with 10 additions and 0 deletions

View file

@ -355,6 +355,7 @@ int register_virtio_device(struct virtio_device *dev)
virtio_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
INIT_LIST_HEAD(&dev->vqs);
spin_lock_init(&dev->vqs_list_lock);
/*
* device_add() causes the bus infrastructure to look for a matching

View file

@ -1755,7 +1755,9 @@ static struct virtqueue *vring_create_virtqueue_packed(
cpu_to_le16(vq->packed.event_flags_shadow);
}
spin_lock(&vdev->vqs_list_lock);
list_add_tail(&vq->vq.list, &vdev->vqs);
spin_unlock(&vdev->vqs_list_lock);
return &vq->vq;
err_desc_extra:
@ -2229,7 +2231,9 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index,
memset(vq->split.desc_state, 0, vring.num *
sizeof(struct vring_desc_state_split));
spin_lock(&vdev->vqs_list_lock);
list_add_tail(&vq->vq.list, &vdev->vqs);
spin_unlock(&vdev->vqs_list_lock);
return &vq->vq;
err_extra:
@ -2291,7 +2295,9 @@ void vring_del_virtqueue(struct virtqueue *_vq)
{
struct vring_virtqueue *vq = to_vvq(_vq);
spin_lock(&vq->vq.vdev->vqs_list_lock);
list_del(&_vq->list);
spin_unlock(&vq->vq.vdev->vqs_list_lock);
if (vq->we_own_ring) {
if (vq->packed_ring) {
@ -2386,12 +2392,14 @@ void virtio_break_device(struct virtio_device *dev)
{
struct virtqueue *_vq;
spin_lock(&dev->vqs_list_lock);
list_for_each_entry(_vq, &dev->vqs, list) {
struct vring_virtqueue *vq = to_vvq(_vq);
/* Pairs with READ_ONCE() in virtqueue_is_broken(). */
WRITE_ONCE(vq->broken, true);
}
spin_unlock(&dev->vqs_list_lock);
}
EXPORT_SYMBOL_GPL(virtio_break_device);

View file

@ -110,6 +110,7 @@ struct virtio_device {
bool config_enabled;
bool config_change_pending;
spinlock_t config_lock;
spinlock_t vqs_list_lock; /* Protects VQs list access */
struct device dev;
struct virtio_device_id id;
const struct virtio_config_ops *config;