> Hi Konstantin,
>
> On Wed, Apr 10, 2024 at 01:42:29AM -0700, Konstantin Taranov wrote:
> > From: Konstantin Taranov <kotaranov@xxxxxxxxxxxxx>
> >
> > Set netdev and RoCEv2 flag to enable GID population on port 1.
> > Use GIDs of the master netdev. As mc->ports[] stores slave devices,
> > use a helper to get the master netdev.
> >
> > Signed-off-by: Konstantin Taranov <kotaranov@xxxxxxxxxxxxx>
> > ---
> > drivers/infiniband/hw/mana/device.c | 15 +++++++++++++++
> > drivers/infiniband/hw/mana/main.c | 15 +++++++++++----
> > 2 files changed, 26 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/infiniband/hw/mana/device.c
> > b/drivers/infiniband/hw/mana/device.c
> > index 47547a962b19..e7981301d10b 100644
> > --- a/drivers/infiniband/hw/mana/device.c
> > +++ b/drivers/infiniband/hw/mana/device.c
> > @@ -53,6 +53,7 @@ static int mana_ib_probe(struct auxiliary_device
> > *adev, {
> > struct mana_adev *madev = container_of(adev, struct mana_adev,
> adev);
> > struct gdma_dev *mdev = madev->mdev;
> > + struct net_device *upper_ndev;
> > struct mana_context *mc;
> > struct mana_ib_dev *dev;
> > int ret;
> > @@ -79,6 +80,20 @@ static int mana_ib_probe(struct auxiliary_device
> *adev,
> > dev->ib_dev.num_comp_vectors = 1;
> > dev->ib_dev.dev.parent = mdev->gdma_context->dev;
> >
> > + rcu_read_lock(); /* required to get upper dev */
> > + upper_ndev = netdev_master_upper_dev_get_rcu(mc->ports[0]);
> > + if (!upper_ndev) {
> > + rcu_read_unlock();
> > + ibdev_err(&dev->ib_dev, "Failed to get master netdev");
> > + goto free_ib_device;
> > + }
>
> Clang now warns (or errors with CONFIG_WERROR):
>
> drivers/infiniband/hw/mana/device.c:88:6: error: variable 'ret' is used
> uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-
> uninitialized]
> 88 | if (!upper_ndev) {
> | ^~~~~~~~~~~
> drivers/infiniband/hw/mana/device.c:150:9: note: uninitialized use occurs
> here
> 150 | return ret;
> | ^~~
> drivers/infiniband/hw/mana/device.c:88:2: note: remove the 'if' if its
> condition is always false
> 88 | if (!upper_ndev) {
> | ^~~~~~~~~~~~~~~~~~
> 89 | rcu_read_unlock();
> | ~~~~~~~~~~~~~~~~~~
> 90 | ibdev_err(&dev->ib_dev, "Failed to get master netdev");
> |
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 91 | goto free_ib_device;
> | ~~~~~~~~~~~~~~~~~~~~
> 92 | }
> | ~
> drivers/infiniband/hw/mana/device.c:62:9: note: initialize the variable 'ret'
> to silence this warning
> 62 | int ret;
> | ^
> | = 0
> 1 error generated.
>
> I could not really find a consistent return code for when
> netdev_master_upper_dev_get_rcu() fails. -ENODEV?
Thanks for catching this! Yes, I think ret = -ENODEV; is appropriate fix.
Should I send a patch to rdma-next? Or what should I do now to fix this?
Konstantin
>
> Cheers,
> Nathan
>
