Hello Thomas,
On 5/11/22 13:47, Thomas Zimmermann wrote:
Hi Javier
Am 11.05.22 um 13:30 schrieb Javier Martinez Canillas:
Drivers that want to remove registered conflicting framebuffers prior to register their own framebuffer, calls remove_conflicting_framebuffers().
This function takes the registration_lock mutex, to prevent a races when drivers register framebuffer devices. But if a conflicting framebuffer device is found, the underlaying platform device is unregistered and this will lead to the platform driver .remove callback to be called, which in turn will call to the unregister_framebuffer() that takes the same lock.
To prevent this, a struct fb_info.forced_out field was used as indication to unregister_framebuffer() whether the mutex has to be grabbed or not.
A cleaner solution is to drop the lock before platform_device_unregister() so unregister_framebuffer() can take it when called from the fbdev driver, and just grab the lock again after the device has been registered and do a removal loop restart.
Since the framebuffer devices will already be removed, the loop would just finish when no more conflicting framebuffers are found.
Suggested-by: Daniel Vetter daniel.vetter@ffwll.ch Signed-off-by: Javier Martinez Canillas javierm@redhat.com Reviewed-by: Daniel Vetter daniel.vetter@ffwll.ch
I'd like to shrink this patchset. This looks like it can be merged
Same. At least this version dropped a few patches that we had in v4 (related to DRM_FIRMWARE capability flag).
immediately?
Yes, this one is independent of the others and could be merged already.
Best regards Thomas