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Re: [PATCH] ACPI / video: driver must be registered before checking for keypresses

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all,

On Mon, Jan 04, 2016 at 11:22:28PM +0100, Adrien Schildknecht wrote:
> acpi_video_handles_brightness_key_presses() may use an uninitialized mutex.
> The error has been reported by lockdep: DEBUG_LOCKS_WARN_ON(l->magic != l).
> The function assumes that the video driver has been registered before being
> called. As explained in the comment of acpi_video_init(), the registration
> of the video class may be defered and thus may not take place in the init
> function of the module.
> 
> Use completion mechanisms to make sure that
> acpi_video_handles_brightness_key_presses() wait for the completion of
> acpi_video_register() before using the mutex.
> Also get rid of register_count since task completion can replace it.
> 
> Signed-off-by: Adrien Schildknecht <adrien+dev@schischi.me>
> ---
>  drivers/acpi/acpi_video.c | 27 ++++++++++++++-------------
>  1 file changed, 14 insertions(+), 13 deletions(-)
> 
[...]

This patch does fix the problem I was having [1].  Thanks for the fix.

  [1]: https://lkml.org/lkml/2016/1/4/791

Tested-by: Jeremiah Mahler <jmmahler@gmail.com>

-- 
- Jeremiah Mahler
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[PATCH] ACPI / video: driver must be registered before checking for keypresses Adrien Schildknecht <adrien+dev@schischi.me> - 2016-01-04 23:30 +0100
  Re: [PATCH] ACPI / video: driver must be registered before checking  for keypresses Hans de Goede <hdegoede@redhat.com> - 2016-01-05 12:50 +0100
    Re: [PATCH] ACPI / video: driver must be registered before checking for keypresses "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2016-01-05 13:30 +0100
    Re: [PATCH] ACPI / video: driver must be registered before checking  for keypresses Hans de Goede <hdegoede@redhat.com> - 2016-01-14 09:10 +0100
  Re: [PATCH] ACPI / video: driver must be registered before checking  for keypresses Jeremiah Mahler <jmmahler@gmail.com> - 2016-01-06 18:40 +0100

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