Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Mon, 1 Mar 2021 10:33:14 -0500
From:   "Michael S. Tsirkin" <mst@redhat.com>
To:     Jason Wang <jasowang@redhat.com>
Cc:     Eli Cohen <elic@nvidia.com>, linux-kernel@vger.kernel.org,
        virtualization@lists.linux-foundation.org, netdev@vger.kernel.org
Subject: Re: [PATCH] vdpa/mlx5: Fix wrong use of bit numbers
Message-ID: <20210301103214-mutt-send-email-mst@kernel.org>
References: <20210301062817.39331-1-elic@nvidia.com>
 <959916f2-5fc9-bdb4-31ca-632fe0d98979@redhat.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <959916f2-5fc9-bdb4-31ca-632fe0d98979@redhat.com>
Precedence: bulk

On Mon, Mar 01, 2021 at 03:52:45PM +0800, Jason Wang wrote:
> 
> On 2021/3/1 2:28 下午, Eli Cohen wrote:
> > VIRTIO_F_VERSION_1 is a bit number. Use BIT_ULL() with mask
> > conditionals.
> > 
> > Also, in mlx5_vdpa_is_little_endian() use BIT_ULL for consistency with
> > the rest of the code.
> > 
> > Fixes: 1a86b377aa21 ("vdpa/mlx5: Add VDPA driver for supported mlx5 devices")
> > Signed-off-by: Eli Cohen <elic@nvidia.com>
> 
> 
> Acked-by: Jason Wang <jasowang@redhat.com>

And CC stable I guess?

> 
> > ---
> >   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 dc7031132fff..7d21b857a94a 100644
> > --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
> > +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> > @@ -821,7 +821,7 @@ static int create_virtqueue(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtque
> >   	MLX5_SET(virtio_q, vq_ctx, event_qpn_or_msix, mvq->fwqp.mqp.qpn);
> >   	MLX5_SET(virtio_q, vq_ctx, queue_size, mvq->num_ent);
> >   	MLX5_SET(virtio_q, vq_ctx, virtio_version_1_0,
> > -		 !!(ndev->mvdev.actual_features & VIRTIO_F_VERSION_1));
> > +		 !!(ndev->mvdev.actual_features & BIT_ULL(VIRTIO_F_VERSION_1)));
> >   	MLX5_SET64(virtio_q, vq_ctx, desc_addr, mvq->desc_addr);
> >   	MLX5_SET64(virtio_q, vq_ctx, used_addr, mvq->device_addr);
> >   	MLX5_SET64(virtio_q, vq_ctx, available_addr, mvq->driver_addr);
> > @@ -1578,7 +1578,7 @@ static void teardown_virtqueues(struct mlx5_vdpa_net *ndev)
> >   static inline bool mlx5_vdpa_is_little_endian(struct mlx5_vdpa_dev *mvdev)
> >   {
> >   	return virtio_legacy_is_little_endian() ||
> > -		(mvdev->actual_features & (1ULL << VIRTIO_F_VERSION_1));
> > +		(mvdev->actual_features & BIT_ULL(VIRTIO_F_VERSION_1));
> >   }
> >   static __virtio16 cpu_to_mlx5vdpa16(struct mlx5_vdpa_dev *mvdev, u16 val)