Re: [PATCH v3 0/8] vhost: Reset batched descriptors on SET_VRING_BASE call

Christian Borntraeger
2020-04-01T07:19:20Z

On 31.03.20 21:27, Eugenio Pérez wrote:
> 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.

>
> v3:
> * Rename accesors functions.
> * Make scsi and test use the accesors too.
>
> v2:
> * Squashed commits.
> * Create vq private_data accesors (mst).
>
> This is meant to be applied on top of
> c4f1c41a6094582903c75c0dcfacb453c959d457 in
> git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git.

A quick test on s390 looks good.