Re: [PATCH v3 07/16] libqos: enforce Device Initialization order

[Thomas Huth]

On 19/10/2019 08.38, Stefan Hajnoczi wrote:
> According to VIRTIO 1.1 "3.1.1 Driver Requirements: Device
> Initialization", configuration space and virtqueues cannot be accessed
> before features have been negotiated.  Enforce this requirement.
> 
> Signed-off-by: Stefan Hajnoczi <address@hidden>
> ---
>  tests/libqos/virtio.c | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/tests/libqos/virtio.c b/tests/libqos/virtio.c
> index 4f7e6bb8a1..2593996c98 100644
> --- a/tests/libqos/virtio.c
> +++ b/tests/libqos/virtio.c
> @@ -13,23 +13,33 @@
>  #include "standard-headers/linux/virtio_config.h"
>  #include "standard-headers/linux/virtio_ring.h"
>  
> +/* Features must be negotiated before config space or virtqueue access */
> +static void check_features_negotiated(QVirtioDevice *d)
> +{
> +    g_assert_cmphex(d->features, !=, 0);
> +}

Isn't it "legal" to negotiate 0 feature bits, too (for legacy devices)?

 Thomas