| Message ID | 20180322080233.17266-1-daniel.vetter@ffwll.ch (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 03/22/2018 10:02 AM, Daniel Vetter wrote: > It published s/It/If > the gem object to userspace, by that point other threads > can guess the id and start using it. And gem IDs are _very_ easy to > guess (it's just an idr). > > Since gem objects is the only thing we allow drivers to create > themselves (all the kms/prime/syncobj stuff is handled by the core) no > other functions seem to be in need of this clarification. > > Motivated by reviewing the xen-front kms driver. > > Cc: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> > Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> > --- > drivers/gpu/drm/drm_gem.c | 9 ++++++--- > 1 file changed, 6 insertions(+), 3 deletions(-) > > diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c > index 4975ba9a7bc8..4a16d7b26c89 100644 > --- a/drivers/gpu/drm/drm_gem.c > +++ b/drivers/gpu/drm/drm_gem.c > @@ -436,9 +436,12 @@ drm_gem_handle_create_tail(struct drm_file *file_priv, > * @obj: object to register > * @handlep: pionter to return the created handle to the caller > * > - * Create a handle for this object. This adds a handle reference > - * to the object, which includes a regular reference count. Callers > - * will likely want to dereference the object afterwards. > + * Create a handle for this object. This adds a handle reference to the object, > + * which includes a regular reference count. Callers will likely want to > + * dereference the object afterwards. > + * > + * Since this publishes @obj to userspace it must be fully set up by this point, > + * drivers must call this last in their buffer object creation callbacks. > */ > int drm_gem_handle_create(struct drm_file *file_priv, > struct drm_gem_object *obj, Reviewed-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
On Thu, Mar 22, 2018 at 10:12:03AM +0200, Oleksandr Andrushchenko wrote: > On 03/22/2018 10:02 AM, Daniel Vetter wrote: > > It published > s/It/If Doesn't make much sense to me, It = drm_gem_handle_create. > > the gem object to userspace, by that point other threads > > can guess the id and start using it. And gem IDs are _very_ easy to > > guess (it's just an idr). > > > > Since gem objects is the only thing we allow drivers to create > > themselves (all the kms/prime/syncobj stuff is handled by the core) no > > other functions seem to be in need of this clarification. > > > > Motivated by reviewing the xen-front kms driver. > > > > Cc: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> > > Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> > > --- > > drivers/gpu/drm/drm_gem.c | 9 ++++++--- > > 1 file changed, 6 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c > > index 4975ba9a7bc8..4a16d7b26c89 100644 > > --- a/drivers/gpu/drm/drm_gem.c > > +++ b/drivers/gpu/drm/drm_gem.c > > @@ -436,9 +436,12 @@ drm_gem_handle_create_tail(struct drm_file *file_priv, > > * @obj: object to register > > * @handlep: pionter to return the created handle to the caller > > * > > - * Create a handle for this object. This adds a handle reference > > - * to the object, which includes a regular reference count. Callers > > - * will likely want to dereference the object afterwards. > > + * Create a handle for this object. This adds a handle reference to the object, > > + * which includes a regular reference count. Callers will likely want to > > + * dereference the object afterwards. > > + * > > + * Since this publishes @obj to userspace it must be fully set up by this point, > > + * drivers must call this last in their buffer object creation callbacks. > > */ > > int drm_gem_handle_create(struct drm_file *file_priv, > > struct drm_gem_object *obj, > > Reviewed-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> Applied, thx for review. -Daniel
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index 4975ba9a7bc8..4a16d7b26c89 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -436,9 +436,12 @@ drm_gem_handle_create_tail(struct drm_file *file_priv, * @obj: object to register * @handlep: pionter to return the created handle to the caller * - * Create a handle for this object. This adds a handle reference - * to the object, which includes a regular reference count. Callers - * will likely want to dereference the object afterwards. + * Create a handle for this object. This adds a handle reference to the object, + * which includes a regular reference count. Callers will likely want to + * dereference the object afterwards. + * + * Since this publishes @obj to userspace it must be fully set up by this point, + * drivers must call this last in their buffer object creation callbacks. */ int drm_gem_handle_create(struct drm_file *file_priv, struct drm_gem_object *obj,
It published the gem object to userspace, by that point other threads can guess the id and start using it. And gem IDs are _very_ easy to guess (it's just an idr). Since gem objects is the only thing we allow drivers to create themselves (all the kms/prime/syncobj stuff is handled by the core) no other functions seem to be in need of this clarification. Motivated by reviewing the xen-front kms driver. Cc: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> --- drivers/gpu/drm/drm_gem.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)