On Fri, Apr 23, 2010 at 8:22 PM, Alan Cox <alan@xxxxxxxxxxxxxxxxxxx> wrote: > > Various bits of the DRM deal with minor->master: > > In the case of the open helper its protected by the struct mutex. > > In the release path it's protected on some paths, but not this one ... > > /* if the master has gone away we can't do anything with the lock */ > if (file_priv->minor->master) > drm_master_release(dev, filp); > > and I can't see what makes this safe if the drm_release for the master > and a client occur at the same time ? lock_kernel in drm_release. We probably need to clean that up. > > The setmaster/dropmaster ioctl seems similar - the various conditional > checks are not protected from parallel changes occuring during their > execution. > > Is this a bug or is something clever afoot ? These ioctls are also under the BKL. So yes its nasty, and we should probably grow a minor lock to protect that. Dave. _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
