pull virtio/vhost fixes from Michael Tsirkin:
"This fixes a couple of bugs triggered by hot-unplug of virtio devices,
as well as a regression in vhost-net"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
vhost/net: length miscalculation
virtio_pci: document why we defer kfree
virtio_pci: defer kfree until release callback
virtio_pci: device-specific release callback
virtio: make del_vqs idempotent