> -----Original Message----- > From: Alex Williamson <[email protected]> > Sent: Tuesday, August 27, 2019 8:54 PM > To: Parav Pandit <[email protected]> > Cc: Mark Bloch <[email protected]>; Jiri Pirko <[email protected]>; > [email protected]; [email protected]; [email protected]; > [email protected]; [email protected]; [email protected] > Subject: Re: [PATCH 2/4] mdev: Make mdev alias unique among all mdevs > > On Tue, 27 Aug 2019 04:28:37 +0000 > Parav Pandit <[email protected]> wrote: > > > Hi Mark, > > > > > -----Original Message----- > > > From: Mark Bloch <[email protected]> > > > Sent: Tuesday, August 27, 2019 4:32 AM > > > To: Parav Pandit <[email protected]>; [email protected]; > > > Jiri Pirko <[email protected]>; [email protected]; > > > [email protected]; [email protected] > > > Cc: [email protected]; [email protected]; > > > [email protected] > > > Subject: Re: [PATCH 2/4] mdev: Make mdev alias unique among all > > > mdevs > > > > > > > > > > > > On 8/26/19 1:41 PM, Parav Pandit 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 <[email protected]> > > > > --- > > > > drivers/vfio/mdev/mdev_core.c | 5 +++++ > > > > 1 file changed, 5 insertions(+) > > > > > > > > diff --git a/drivers/vfio/mdev/mdev_core.c > > > > b/drivers/vfio/mdev/mdev_core.c index e825ff38b037..6eb37f0c6369 > > > > 100644 > > > > --- a/drivers/vfio/mdev/mdev_core.c > > > > +++ b/drivers/vfio/mdev/mdev_core.c > > > > @@ -375,6 +375,11 @@ int mdev_device_create(struct kobject *kobj, > > > struct device *dev, > > > > ret = -EEXIST; > > > > goto mdev_fail; > > > > } > > > > + if (tmp->alias && strcmp(tmp->alias, alias) == 0) { > > > > > > alias can be NULL here no? > > > > > If alias is NULL, tmp->alias would also be null because for given parent > > either > we have alias or we don’t. > > So its not possible to have tmp->alias as null and alias as non null. > > But it may be good/defensive to add check for both. > > mdev_list is a global list of all mdev devices, how can we make any > assumptions that an element has the same parent? Thanks, > Oh yes, right. If tmp->alias is not_null but alias can be NULL. I will fix the check.
> Alex > > > > > + mutex_unlock(&mdev_list_lock); > > > > + ret = -EEXIST; > > > > + goto mdev_fail; > > > > + } > > > > } > > > > > > > > mdev = kzalloc(sizeof(*mdev), GFP_KERNEL); > > > > > > > > > > Mark
