Quoting Daniel Vetter (2020-07-27 20:32:45) > On Thu, Jul 23, 2020 at 7:21 PM Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> wrote: > > > > An unfortunate sequence of events, but it turns out there is a valid > > usecase for being able to free/decouple the driver objects before they > > are freed by the DRM core. In particular, if we have a pointer into a > > drm core object from inside a driver object, that pointer needs to be > > nerfed *before* it is freed so that concurrent access (e.g. debugfs) > > does not following the dangling pointer. > > > > The legacy marker was adding in the code movement from drp_fops.c to > > drm_file.c > > I might fumble a lot, but not this one: > > commit 45c3d213a400c952ab7119f394c5293bb6877e6b > Author: Daniel Vetter <daniel.vetter@xxxxxxxx> > Date: Mon May 8 10:26:33 2017 +0200 > > drm: Nerf the preclose callback for modern drivers Gah, when I going through the history it looked like it appeared out of nowhere. > Also looking at the debugfs hook that has some rather adventurous > stuff going on I think, feels a bit like a kitchensink with batteries > included. If that's really all needed I'd say iterate the contexts by > first going over files, then the ctx (which arent shared anyway) and > the problem should also be gone. Or we could cut out the middlelayer and put the release under the driver control with a call to the drm_release() when the driver is ready. -Chris
