From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jason Wang <jasowang@redhat.com>
Subject: Re: [PATCH 1/2] virito: introduce methods of fixing device features
Date: Thu, 13 Nov 2014 17:49:42 +0800
Message-ID: <54647EB6.5030507@redhat.com>
References: <1415857974-23326-1-git-send-email-jasowang@redhat.com>	<20141113094604.1f248c3d.cornelia.huck@de.ibm.com>	<546475C2.50606@redhat.com>
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To: Cornelia Huck <cornelia.huck@de.ibm.com>
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On 11/13/2014 05:14 PM, Cornelia Huck wrote:
> On Thu, 13 Nov 2014 17:11:30 +0800
> Jason Wang <jasowang@redhat.com> wrote:
>
>> On 11/13/2014 04:46 PM, Cornelia Huck wrote:
>>> On Thu, 13 Nov 2014 13:52:53 +0800
>>> Jason Wang <jasowang@redhat.com> wrote:
>>>> +static inline void virtio_disable_feature(struct virtio_device *vdev,
>>>> +                                          unsigned int fbit)
>>>> +{
>>>> +	BUG_ON(fbit >= VIRTIO_TRANSPORT_F_START);
>>>> +	BUG_ON(vdev->config->get_status(vdev) &
>>>> +	       ~(VIRTIO_CONFIG_S_ACKNOWLEDGE | VIRTIO_CONFIG_S_DRIVER));
>>> When we add virtio-1 support, we can add a check for FEATURES_OK here,
>>> so we're really on the safe side.
>>>
>> If I read the spec correctly, FEATURES_OK was set only after writing the
>> features bits to device. But we want to sanitize the them before.
> I meant doing a BUG when FEATURES_OK is set - sorry for not being clear.
>

I get it, thanks for the clarification.