Re: [PATCH v2] content: enhance device requirements for feature bits

[Cornelia Huck <cohuck@redhat.com>]

On Fri,  8 Jun 2018 16:12:36 +0800
Tiwei Bie <tiwei.bie@intel.com> wrote:

> Suggested-by: Michael S. Tsirkin <mst@redhat.com>
> Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
> Fixes: https://github.com/oasis-tcs/virtio-spec/issues/14
> ---
> v2:
> - Refine the wording (Cornelia);
> 
>  content.tex | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/content.tex b/content.tex
> index f996fad..41cba41 100644
> --- a/content.tex
> +++ b/content.tex
> @@ -125,6 +125,13 @@ which was not offered.  The device SHOULD accept any valid subset
>  of features the driver accepts, otherwise it MUST fail to set the
>  FEATURES_OK \field{device status} bit when the driver writes it.
>  
> +If a device has successfully negotiated a set of features
> +at least once (by succeeding to set the FEATURES_OK
> +\field{device status} bit when the driver writes it), then
> +it SHOULD NOT fail re-negotiation of the same set of features
> +after a device or system reset.  Failure to do so would
> +interfere with resuming from suspend and error recovery.
> +
>  \subsection{Legacy Interface: A Note on Feature
>  Bits}\label{sec:Basic Facilities of a Virtio Device / Feature
>  Bits / Legacy Interface: A Note on Feature Bits}

Reviewed-by: Cornelia Huck <cohuck@redhat.com>