2.6.36 appears to respect the 0400 mode we assigned to the parameter
preventing it from being adjusted after loading. However, this is safe
to adjust at runtime.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=31311Reported-by: NFernando Lemos <fernandotcl@gmail.com>
Cc: stable@kernel.org
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>