From 0e566c8f0f2e8325e35f6f97e13cde5356b41814 Mon Sep 17 00:00:00 2001 From: Parav Pandit Date: Wed, 21 Jul 2021 17:26:47 +0300 Subject: 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: e2dcdfe95c0b ("virtio: virtio_break_device() to mark all virtqueues broken.") Signed-off-by: Parav Pandit Link: https://lore.kernel.org/r/20210721142648.1525924-4-parav@nvidia.com Signed-off-by: Michael S. Tsirkin --- drivers/virtio/virtio.c | 1 + drivers/virtio/virtio_ring.c | 8 ++++++++ 2 files changed, 9 insertions(+) (limited to 'drivers/virtio') diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c index 4b15c00c0a0a..49984d2cba24 100644 --- a/drivers/virtio/virtio.c +++ b/drivers/virtio/virtio.c @@ -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 diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index d5934c2e5a89..c2aaa0eff6df 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -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); -- cgit