[v4,0/7] vhost: Reset batched descriptors on SET_VRING_BASE call

Message

Eugenio Perez Martin April 1, 2020, 6:31 p.m. UTC

Vhost did not reset properly the batched descriptors on SET_VRING_BASE
event. Because of that, is possible to return an invalid descriptor to
the guest.

This series ammend this, resetting them every time backend changes, and
creates a test to assert correct behavior. To do that, they need to
expose a new function in virtio_ring, virtqueue_reset_free_head, only
on test code.

Another useful thing would be to check if mutex is properly get in
vq private_data accessors. Not sure if mutex debug code allow that,
similar to C++ unique lock::owns_lock. Not acquiring in the function
because caller code holds the mutex in order to perform more actions.

v4:
* Rebase with vhost_iotlb changes.

v3:
* Rename accesors functions.
* Make scsi and test use the accesors too.

v2:
* Squashed commits.
* Create vq private_data accesors (mst).

This serie is meant to be applied on top of
38dd2ba72ece18ec8398c8ddd13cfb02870b0309 in
git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git.

Eugenio Pérez (4):
  tools/virtio: Add --batch option
  tools/virtio: Add --batch=random option
  tools/virtio: Add --reset=random
  tools/virtio: Make --reset reset ring idx

Michael S. Tsirkin (3):
  vhost: option to fetch descriptors through an independent struct
  vhost: use batched version by default
  vhost: batching fetches

 drivers/vhost/test.c         |  59 +++++++-
 drivers/vhost/test.h         |   1 +
 drivers/vhost/vhost.c        | 271 +++++++++++++++++++++++------------
 drivers/vhost/vhost.h        |  17 ++-
 drivers/virtio/virtio_ring.c |  29 ++++
 tools/virtio/linux/virtio.h  |   2 +
 tools/virtio/virtio_test.c   | 123 ++++++++++++++--
 7 files changed, 395 insertions(+), 107 deletions(-)