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<9d6058d6-5ce1-0442-8fd9-5a6fe6a0bc6b@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: <9d6058d6-5ce1-0442-8fd9-5a6fe6a0bc6b@redhat.com> User-Agent: Mutt/1.9.5 (bf161cf53efb) (2018-04-13) X-Originating-IP: [172.20.145.6] X-ClientProxiedBy: HQMAIL105.nvidia.com (172.20.187.12) To HQMAIL107.nvidia.com (172.20.187.13) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1612249031; bh=QLhWKEGKgMKk+GS5l4zd0izvmgX0aProgpn8vewZ8JM=; h=Date:From:To:CC:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:Content-Transfer-Encoding: In-Reply-To:User-Agent:X-Originating-IP:X-ClientProxiedBy; b=fln5zs7B6b0/K0bvd4exy8x5us8EDErORDsV23diUpkamWLpzVbMM6z6P7j+lit1o kwxpkq3KKvRrd+zG/Y9m4pxxbz4IvnJTVA1Mj/s6mXE61wyF6iD7I9yi90nydP1R8R hM/AKs955cqnY9kWG+FYAGSjgfnyZNNQKK6rOYO+H5FiSwGr1lvtDcFXXQyaLzw2EL 5VGghtTKmrj1k7B2Ln+f4YV8qFFog5F+z1cjFMO+1NirJM4L3Ix2vwT4YeJlQJAP/D 419D9B+EGy/GnaPumI2yFfE9NKr1DNzBhdO85qaPBDnGzKtZ9DcbZVn7pWFZXtyr9Y p21/EidrmR8mQ== Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Feb 02, 2021 at 11:12:51AM +0800, Jason Wang wrote: >=20 > On 2021/2/2 =E4=B8=8A=E5=8D=883:17, Si-Wei Liu wrote: > > On Mon, Feb 1, 2021 at 10:51 AM Si-Wei Liu wr= ote: > > > On Thu, Jan 28, 2021 at 5:46 AM Eli Cohen wrote: > > > > suspend_vq should only suspend the VQ on not save the current avail= able > > > > index. This is done when a change of map occurs when the driver cal= ls > > > > save_channel_info(). > > > Hmmm, suspend_vq() is also called by teardown_vq(), the latter of > > > which doesn't save the available index as save_channel_info() doesn't > > > get called in that path at all. How does it handle the case that > > > aget_vq_state() is called from userspace (e.g. QEMU) while the > > > hardware VQ object was torn down, but userspace still wants to access > > > the queue index? > > >=20 > > > Refer to https://lore.kernel.org/netdev/1601583511-15138-1-git-send-e= mail-si-wei.liu@oracle.com/ > > >=20 > > > vhost VQ 0 ring restore failed: -1: Resource temporarily unavailable = (11) > > > vhost VQ 1 ring restore failed: -1: Resource temporarily unavailable = (11) > > >=20 > > > QEMU will complain with the above warning while VM is being rebooted > > > or shut down. > > >=20 > > > Looks to me either the kernel driver should cover this requirement, o= r > > > the userspace has to bear the burden in saving the index and not call > > > into kernel if VQ is destroyed. > > Actually, the userspace doesn't have the insights whether virt queue > > will be destroyed if just changing the device status via set_status(). > > Looking at other vdpa driver in tree i.e. ifcvf it doesn't behave like > > so. Hence this still looks to me to be Mellanox specifics and > > mlx5_vdpa implementation detail that shouldn't expose to userspace. >=20 >=20 > So I think we can simply drop this patch? >=20 Yes, I agree. Let's just avoid it. > Thanks >=20 >=20 > > > -Siwei > > >=20 > > >=20 > > > > Signed-off-by: Eli Cohen > > > > --- > > > > drivers/vdpa/mlx5/net/mlx5_vnet.c | 8 -------- > > > > 1 file changed, 8 deletions(-) > > > >=20 > > > > diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/= net/mlx5_vnet.c > > > > index 88dde3455bfd..549ded074ff3 100644 > > > > --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c > > > > +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c > > > > @@ -1148,8 +1148,6 @@ static int setup_vq(struct mlx5_vdpa_net *nde= v, struct mlx5_vdpa_virtqueue *mvq) > > > >=20 > > > > static void suspend_vq(struct mlx5_vdpa_net *ndev, struct mlx5_vd= pa_virtqueue *mvq) > > > > { > > > > - struct mlx5_virtq_attr attr; > > > > - > > > > if (!mvq->initialized) > > > > return; > > > >=20 > > > > @@ -1158,12 +1156,6 @@ static void suspend_vq(struct mlx5_vdpa_net = *ndev, struct mlx5_vdpa_virtqueue *m > > > >=20 > > > > if (modify_virtqueue(ndev, mvq, MLX5_VIRTIO_NET_Q_OBJECT_S= TATE_SUSPEND)) > > > > mlx5_vdpa_warn(&ndev->mvdev, "modify to suspend fa= iled\n"); > > > > - > > > > - if (query_virtqueue(ndev, mvq, &attr)) { > > > > - mlx5_vdpa_warn(&ndev->mvdev, "failed to query virtq= ueue\n"); > > > > - return; > > > > - } > > > > - mvq->avail_idx =3D attr.available_index; > > > > } > > > >=20 > > > > static void suspend_vqs(struct mlx5_vdpa_net *ndev) > > > > -- > > > > 2.29.2 > > > >=20 >=20