On Fri, Apr 23, 2010 at 8:37 PM, Alan Cox <alan@xxxxxxxxxxxxxxxxxxx> wrote: >> > 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. > > I don't think that works. drm_open_helper doesn't appear to be under the > BKL merely the struct mutex. It blocks the case you specified of two releases happening together. > >> > 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. > > But setmaster can sleep so the BKL is dropped on contention of the > struct_mutex, ditto dropmaster they should only sleep in the mutex lock nuless the driver callback is allocating memory. but yeah its a bit of a mess. Dave. _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
