RE: [PATCH net-next 08/19] vfio/mdev: Make mdev alias unique among all mdevs

Parav Pandit
2019-11-08T15:13:27Z

> -----Original Message-----
> From: Jiri Pirko <jiri@resnulli.us>
> Sent: Friday, November 8, 2019 4:50 AM
> To: Parav Pandit <parav@mellanox.com>
> Cc: alex.williamson@redhat.com; davem@davemloft.net;
> kvm@vger.kernel.org; netdev@vger.kernel.org; Saeed Mahameed
> <saeedm@mellanox.com>; kwankhede@nvidia.com; leon@kernel.org;
> cohuck@redhat.com; Jiri Pirko <jiri@mellanox.com>; linux-
> rdma@vger.kernel.org
> Subject: Re: [PATCH net-next 08/19] vfio/mdev: Make mdev alias unique
> among all mdevs
>
> Thu, Nov 07, 2019 at 05:08:23PM CET, parav@mellanox.com wrote:
> >Mdev alias should be unique among all the mdevs, so that when such
> >alias is used by the mdev users to derive other objects, there is no
> >collision in a given system.
> >
> >Reviewed-by: Saeed Mahameed <saeedm@mellanox.com>
> >Signed-off-by: Parav Pandit <parav@mellanox.com>
> >---
> > drivers/vfio/mdev/mdev_core.c | 7 +++++++
> > 1 file changed, 7 insertions(+)
> >
> >diff --git a/drivers/vfio/mdev/mdev_core.c
> >b/drivers/vfio/mdev/mdev_core.c index 3bdff0469607..c8cd40366783
> 100644
> >--- a/drivers/vfio/mdev/mdev_core.c
> >+++ b/drivers/vfio/mdev/mdev_core.c
> >@@ -388,6 +388,13 @@ int mdev_device_create(struct kobject *kobj, struct
> device *dev,
> > ret = -EEXIST;
> > goto mdev_fail;
> > }
> >+ if (alias && tmp->alias && !strcmp(alias, tmp->alias)) {
> >+ mutex_unlock(&mdev_list_lock);
> >+ ret = -EEXIST;
> >+ dev_dbg_ratelimited(dev, "Hash collision in alias
> creation for UUID %pUl\n",
> >+ uuid);
> >+ goto mdev_fail;
> >+ }
>
> I don't understand why this needs to be a separate patch. This check seems
> to be an inseparable part of mdev alias feature.
> Please squash to the previous patch.
>
Ok. Cornelia had the same comment too.
The previous patch had relatively more delta, and since this patch can be split functionally,
I kept it as separate one.
Either way works.

>
> > }
> >
> > mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
> >--
> >2.19.2
> >