virtio_random: defer first enqueue until after DRIVER_OKHEADmain

According to the virtio spec:

> The driver MUST NOT send any buffer available notifications to the
> device before setting DRIVER_OK.

DRIVER_OK isn't set until after attach completes, so defer the first
enqueue.  We haven't found any problems as a result of this to the best
of my knowledge: q35 and other devices that we *have* been used with
will apparently check when we go DRIVER_OK.

Tested with q35 virtio-random, which still works.

Reported by:	llm-postcr
Reviewed by:	kfv, markj
Fixes:	f1c5a2e3a62505 ("virtio_random: Pipeline fetching the data")
Sponsored by:	Stormshield
Sponsored by:	Klara, Inc.
Differential Revision:	https://reviews.freebsd.org/D61228

0 files changed, 0 insertions, 0 deletions