Hi, I've been debugging omapdrm issues on top of the latest drm mainline changes. Sometimes a drm_framebuffer ref count drops to -1 when aborting a drm application, or unloading the modules.
The setup is very basic, just a single crtc with the crtc's primary plane. What seems to happen is: - App is started - fb is created, and taken into use by omapdrm. omapdrm takes a ref to the fb. - the app is starts to shut down - drm_framebuffer_remove is called - fb->refcount.refcount > 1, so it goes to disable stuff - drm_plane_force_disable is called for the primary plane - drm_plane_force_disable does plane->disable_plane, which on omapdrm puts stuff on a workqueue as plane cannot be disabled immediately - drm_plane_force_disable calls __drm_framebuffer_unreference() - at the end of drm_framebuffer_remove(), there's drm_framebuffer_unreference, which causes ref count to go to zero, and the fb to be destroyed - a bit later, the queued work is ran, which does drm_framebuffer_unreference(), and ref count goes to -1. Here omapdrm is removing the ref that had been taken in the beginning. So the explicit unref done by drm_plane_force_disable() seems a bit out of place. I can't figure out which drm_framebuffer_reference() would be the matching one for the unref done by drm_plane_force_disable(). Any ideas what ref is that? Or is the __drm_framebuffer_unreference() extra in drm_plane_force_disable()? Tomi -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 836 bytes Desc: OpenPGP digital signature URL: <http://lists.freedesktop.org/archives/dri-devel/attachments/20140410/dec5cde4/attachment.sig>