77ab9d4d44
acpi_video_set_dmi_backlight_type() is troublesome because it may end up getting called after other backlight drivers have already called acpi_video_get_backlight_type() resulting in the other drivers already being registered even though they should not. In case of the acpi_video backlight, acpi_video_set_dmi_backlight_type() actually calls acpi_video_unregister_backlight() since that is often probed earlier, leading to userspace seeing the acpi_video0 class device being briefly available, leading to races in userspace where udev probe-rules try to access the device and it is already gone. All callers have been fixed to no longer call it, so remove acpi_video_set_dmi_backlight_type() now. This means we now also no longer need acpi_video_unregister_backlight() for the remove acpi_video backlight after it was wrongly registered hack, so remove that too. Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.