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From:   Jason Wang <jasowang@redhat.com>
Date:   Tue, 11 Apr 2023 11:09:46 +0800
Message-ID: <CACGkMEvTdgvqacFmMJZD4u++YJwESgSmLF6CMdAJBBqkxpZKgg@mail.gmail.com>
Subject: Re: [PATCH] vhost_vdpa: fix unmap process in no-batch mode
To:     Cindy Lu <lulu@redhat.com>
Cc:     mst@redhat.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
        virtualization@lists.linux-foundation.org, netdev@vger.kernel.org
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On Mon, Apr 10, 2023 at 11:01=E2=80=AFPM Cindy Lu <lulu@redhat.com> wrote:
>
> While using the no-batch mode, the process will not begin with
> VHOST_IOTLB_BATCH_BEGIN, so we need to add the
> VHOST_IOTLB_INVALIDATE to get vhost_vdpa_as, the process is the
> same as VHOST_IOTLB_UPDATE
>
> Signed-off-by: Cindy Lu <lulu@redhat.com>
> ---
>  drivers/vhost/vdpa.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
> index 7be9d9d8f01c..32636a02a0ab 100644
> --- a/drivers/vhost/vdpa.c
> +++ b/drivers/vhost/vdpa.c
> @@ -1074,6 +1074,7 @@ static int vhost_vdpa_process_iotlb_msg(struct vhos=
t_dev *dev, u32 asid,
>                 goto unlock;
>
>         if (msg->type =3D=3D VHOST_IOTLB_UPDATE ||
> +           msg->type =3D=3D VHOST_IOTLB_INVALIDATE ||

I'm not sure I get here, invalidation doesn't need to create a new AS.

Or maybe you can post the userspace code that can trigger this issue?

Thanks

>             msg->type =3D=3D VHOST_IOTLB_BATCH_BEGIN) {
>                 as =3D vhost_vdpa_find_alloc_as(v, asid);
>                 if (!as) {
> --
> 2.34.3
>