On Mon, Sep 07, 2020 at 07:34:00AM -0400, Michael S. Tsirkin wrote:
> On Mon, Sep 07, 2020 at 10:51:36AM +0300, Eli Cohen wrote:
> > If the memory map changes before the driver status is
> > VIRTIO_CONFIG_S_DRIVER_OK, don't attempt to create resources because it
> > may fail. For example, if the VQ is not ready there is no point in
> > creating resources.
> >
> > Fixes: 1a86b377aa21 ("vdpa/mlx5: Add VDPA driver for supported mlx5
> > devices")
> > Signed-off-by: Eli Cohen <e...@nvidia.com>
>
>
> Could you add a bit more data about the problem to the log?
> To be more exact, what exactly happens right now?
>
Sure I can.
set_map() is used by mlx5 vdpa to create a memory region based on the
address map passed by the iotlb argument. If I get successive calls, I
will destroy the current memory region and build another one based on
the new address mapping. I also need to setup the hardware resources
since they depend on the memory region.
If these calls happen before DRIVER_OK, It means it that driver VQs may
also not been setup and I may not create them yet. In this case I want
to avoid setting up the other resources and defer this till I get DRIVER
OK.
Let me know if that answers your question so I can post another patch.
> > ---
> > drivers/vdpa/mlx5/net/mlx5_vnet.c | 3 +++
> > 1 file changed, 3 insertions(+)
> >
> > diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c
> > b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> > index 9df69d5efe8c..c89cd48a0aab 100644
> > --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
> > +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> > @@ -1645,6 +1645,9 @@ static int mlx5_vdpa_change_map(struct mlx5_vdpa_net
> > *ndev, struct vhost_iotlb *
> > if (err)
> > goto err_mr;
> >
> > + if (!(ndev->mvdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
> > + return 0;
> > +
> > restore_channels_info(ndev);
> > err = setup_driver(ndev);
> > if (err)
> > --
> > 2.26.0
>
