Re: [PATCH] vdpa/mlx5: Extract correct pointer from driver data

From: Leon Romanovsky
Date: Tue Feb 16 2021 - 08:19:03 EST


On Tue, Feb 16, 2021 at 02:45:40PM +0200, Eli Cohen wrote:
> On Tue, Feb 16, 2021 at 09:37:34AM +0200, Leon Romanovsky wrote:
> > On Tue, Feb 16, 2021 at 08:42:26AM +0200, Eli Cohen wrote:
> > > On Tue, Feb 16, 2021 at 08:35:51AM +0200, Leon Romanovsky wrote:
> > > > On Tue, Feb 16, 2021 at 07:50:22AM +0200, Eli Cohen wrote:
> > > > > struct mlx5_vdpa_net pointer was stored in drvdata. Extract it as well
> > > > > in mlx5v_remove().
> > > > >
> > > > > Fixes: 74c9729dd892 ("vdpa/mlx5: Connect mlx5_vdpa to auxiliary bus")
> > > > > Signed-off-by: Eli Cohen <elic@xxxxxxxxxx>
> > > > > ---
> > > > > drivers/vdpa/mlx5/net/mlx5_vnet.c | 4 ++--
> > > > > 1 file changed, 2 insertions(+), 2 deletions(-)
> > > > >
> > > > > diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> > > > > index 6b0a42183622..4103d3b64a2a 100644
> > > > > --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
> > > > > +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> > > > > @@ -2036,9 +2036,9 @@ static int mlx5v_probe(struct auxiliary_device *adev,
> > > > >
> > > > > static void mlx5v_remove(struct auxiliary_device *adev)
> > > > > {
> > > > > - struct mlx5_vdpa_dev *mvdev = dev_get_drvdata(&adev->dev);
> > > > > + struct mlx5_vdpa_net *ndev = dev_get_drvdata(&adev->dev);
> > > > >
> > > > > - vdpa_unregister_device(&mvdev->vdev);
> > > > > + vdpa_unregister_device(&ndev->mvdev.vdev);
> > > > > }
> > > >
> > > > IMHO, The more correct solution is to fix dev_set_drvdata() call,
> > > > because we are regustering/unregistering/allocating "struct mlx5_vdpa_dev".
> > > >
> > >
> > > We're allocating "struct mlx5_vdpa_net". "struct mlx5_vdpa_dev" is just
> > > a member field of "struct mlx5_vdpa_net".
> >
> > I referred to these lines in the mlx5v_probe():
> > 1986 err = mlx5_vdpa_alloc_resources(&ndev->mvdev);
> > 1987 if (err)
> > 1988 goto err_mtu;
> > 1989
> > 1990 err = alloc_resources(ndev);
> > 1991 if (err)
> > 1992 goto err_res;
> > 1993
> > 1994 err = vdpa_register_device(&mvdev->vdev);
> >
> > So mlx5v_remove() is better to be symmetrical.
> >
>
> It's "struct mlx5_vdpa_net" that is being allocated here so it makes
> sense to set this pointer as the the driver data.

Anyway, it doesn't important.

Thanks, for the original patch.
Reviewed-by: Leon Romanovsky <leonro@xxxxxxxxxx>