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From: Jason Wang <jasowang@redhat.com>
Date: Wed, 20 Dec 2023 12:05:50 +0800
Message-ID: <CACGkMEsaaDGi63__YrvsTC1HqgTaEWHvGokK1bJS5+m1XYM-6w@mail.gmail.com>
Subject: Re: [PATCH vhost v4 02/15] vdpa: Add VHOST_BACKEND_F_CHANGEABLE_VQ_ADDR_IN_SUSPEND
 flag
To: Dragos Tatulea <dtatulea@nvidia.com>
Cc: "Michael S . Tsirkin" <mst@redhat.com>, Eugenio Perez Martin <eperezma@redhat.com>, 
	Si-Wei Liu <si-wei.liu@oracle.com>, Saeed Mahameed <saeedm@nvidia.com>, 
	Leon Romanovsky <leon@kernel.org>, virtualization@lists.linux-foundation.org, 
	Gal Pressman <gal@nvidia.com>, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, 
	Parav Pandit <parav@nvidia.com>, Xuan Zhuo <xuanzhuo@linux.alibaba.com>
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On Wed, Dec 20, 2023 at 11:46=E2=80=AFAM Jason Wang <jasowang@redhat.com> w=
rote:
>
> On Wed, Dec 20, 2023 at 2:09=E2=80=AFAM Dragos Tatulea <dtatulea@nvidia.c=
om> wrote:
> >
> > The virtio spec doesn't allow changing virtqueue addresses after
> > DRIVER_OK. Some devices do support this operation when the device is
> > suspended. The VHOST_BACKEND_F_CHANGEABLE_VQ_ADDR_IN_SUSPEND flag
> > advertises this support as a backend features.
>
> There's an ongoing effort in virtio spec to introduce the suspend state.
>
> So I wonder if it's better to just allow such behaviour?

Actually I mean, allow drivers to modify the parameters during suspend
without a new feature.

Thanks

>
> Thanks
>
>