On Mon 01 Jun 10:51 PDT 2020, Mathieu Poirier wrote:
> When function rproc_free_vring() clears the virtio device section
> it does so on the cached resource table rather than the one
> installed in the remote processor memory. When a remote processor
> has been booted by another entity there is no need to use a cached
> table and as such, no need to clear the virtio device section in
> it.
>
> Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Regards,
Bjorn
> ---
> drivers/remoteproc/remoteproc_core.c | 20 ++++++++++++++++----
> 1 file changed, 16 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
> index d32ac8f0c872..0e23284fbd25 100644
> --- a/drivers/remoteproc/remoteproc_core.c
> +++ b/drivers/remoteproc/remoteproc_core.c
> @@ -411,10 +411,22 @@ void rproc_free_vring(struct rproc_vring *rvring)
>
> idr_remove(&rproc->notifyids, rvring->notifyid);
>
> - /* reset resource entry info */
> - rsc = (void *)rproc->table_ptr + rvring->rvdev->rsc_offset;
> - rsc->vring[idx].da = 0;
> - rsc->vring[idx].notifyid = -1;
> + /*
> + * At this point rproc_stop() has been called and the installed resource
> + * table in the remote processor memory may no longer be accessible. As
> + * such and as per rproc_stop(), rproc->table_ptr points to the cached
> + * resource table (rproc->cached_table). The cached resource table is
> + * only available when a remote processor has been booted by the
> + * remoteproc core, otherwise it is NULL.
> + *
> + * Based on the above, reset the virtio device section in the cached
> + * resource table only if there is one to work with.
> + */
> + if (rproc->table_ptr) {
> + rsc = (void *)rproc->table_ptr + rvring->rvdev->rsc_offset;
> + rsc->vring[idx].da = 0;
> + rsc->vring[idx].notifyid = -1;
> + }
> }
>
> static int rproc_vdev_do_start(struct rproc_subdev *subdev)
> --
> 2.20.1
>
