Messages in this thread | | | From | "Rafael J. Wysocki" <> | Subject | Re: [PATCH] ACPI / video: driver must be registered before checking for keypresses | Date | Tue, 05 Jan 2016 13:51:17 +0100 |
| |
On Tuesday, January 05, 2016 12:43:54 PM Hans de Goede wrote: > Hi, > > On 04-01-16 23:22, 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> > > Thanks for the fix, my first instinct was that there should be an easier > fix, but thinking more about it this and how this function is used > in thinkpad_acpi. this is indeed the correct way to fix this: > > Reviewed-by: Hans de Goede <hdegoede@redhat.com> > > Rafael, can you please add this fix to acpi-next ?
I will, thanks!
Rafael
| |