| Message ID | 20190827191654.41161-3-parav@mellanox.com |
|---|---|
| State | Not Applicable |
| Delegated to: | David Miller |
| Headers | show |
| Series | Introduce variable length mdev alias | expand |
On Tue, 27 Aug 2019 14:16:51 -0500 Parav Pandit <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. > > Signed-off-by: Parav Pandit <parav@mellanox.com> > > --- > Changelog: > v0->v1: > - Fixed inclusiong of alias for NULL check > - Added ratelimited debug print for sha1 hash collision error > --- > 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 62d29f57fe0c..4b9899e40665 100644 > --- a/drivers/vfio/mdev/mdev_core.c > +++ b/drivers/vfio/mdev/mdev_core.c > @@ -375,6 +375,13 @@ int mdev_device_create(struct kobject *kobj, struct device *dev, > ret = -EEXIST; > goto mdev_fail; > } > + if (tmp->alias && alias && strcmp(tmp->alias, alias) == 0) { Nit, test if the device we adding has an alias before the device we're testing against. The compiler can better optimize keeping alias hot. Thanks, Alex > + mutex_unlock(&mdev_list_lock); > + ret = -EEXIST; > + dev_dbg_ratelimited(dev, "Hash collision in alias creation for UUID %pUl\n", > + uuid); > + goto mdev_fail; > + } > } > > mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
> -----Original Message----- > From: Alex Williamson <alex.williamson@redhat.com> > Sent: Thursday, August 29, 2019 3:07 AM > To: Parav Pandit <parav@mellanox.com> > Cc: Jiri Pirko <jiri@mellanox.com>; kwankhede@nvidia.com; > cohuck@redhat.com; davem@davemloft.net; kvm@vger.kernel.org; linux- > kernel@vger.kernel.org; netdev@vger.kernel.org > Subject: Re: [PATCH v1 2/5] mdev: Make mdev alias unique among all mdevs > > On Tue, 27 Aug 2019 14:16:51 -0500 > Parav Pandit <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. > > > > Signed-off-by: Parav Pandit <parav@mellanox.com> > > > > --- > > Changelog: > > v0->v1: > > - Fixed inclusiong of alias for NULL check > > - Added ratelimited debug print for sha1 hash collision error > > --- > > 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 62d29f57fe0c..4b9899e40665 > > 100644 > > --- a/drivers/vfio/mdev/mdev_core.c > > +++ b/drivers/vfio/mdev/mdev_core.c > > @@ -375,6 +375,13 @@ int mdev_device_create(struct kobject *kobj, struct > device *dev, > > ret = -EEXIST; > > goto mdev_fail; > > } > > + if (tmp->alias && alias && strcmp(tmp->alias, alias) == 0) { > > Nit, test if the device we adding has an alias before the device we're testing > against. The compiler can better optimize keeping alias hot. > Thanks, > Ok. will do. > Alex
diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c index 62d29f57fe0c..4b9899e40665 100644 --- a/drivers/vfio/mdev/mdev_core.c +++ b/drivers/vfio/mdev/mdev_core.c @@ -375,6 +375,13 @@ int mdev_device_create(struct kobject *kobj, struct device *dev, ret = -EEXIST; goto mdev_fail; } + if (tmp->alias && alias && strcmp(tmp->alias, alias) == 0) { + mutex_unlock(&mdev_list_lock); + ret = -EEXIST; + dev_dbg_ratelimited(dev, "Hash collision in alias creation for UUID %pUl\n", + uuid); + goto mdev_fail; + } } mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
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. Signed-off-by: Parav Pandit <parav@mellanox.com> --- Changelog: v0->v1: - Fixed inclusiong of alias for NULL check - Added ratelimited debug print for sha1 hash collision error --- drivers/vfio/mdev/mdev_core.c | 7 +++++++ 1 file changed, 7 insertions(+)