[PATCH RFC] virtio_net: fix refill related races

Rusty Russell
Thu, 08 Dec 2011 04:37:29 -0000

On Wed, 7 Dec 2011 17:21:22 +0200, "Michael S. Tsirkin" <mst at
redhat.com> wrote:
> Fix theoretical races related to refill work:
> 1. After napi is disabled by ndo_stop, refill work
>    can run and re-enable it.
> 2. Refill can reschedule itself, if this happens
>    it can run after cancel_delayed_work_sync,
>    and will access device after it is destroyed.
>
> As a solution, add flags to track napi state and
> to disable refill, and toggle them on start, stop
> and remove; check these flags on refill.

Why isn't a "dont-readd" flag sufficient?

Cheers,
Rusty.