drm/i915: Avoid NULL dereference with component_only tv_modes
commit
d271817baecbccb47da0d9f28c285a0dae8a06b7 upstream.
In commit
d2d9f2324, the guard for a valid video mode was removed. This
caused the regression:
kernel crash during kms graphic boot on Intel GM4500 platform
https://bugzilla.redhat.com/show_bug.cgi?id=540218
This patches changes the logic slightly not to rely on a coupled
variable, but to just check whether the video_modes is valid before
dereferencing.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Zhenyu Wang <zhenyu.z.wang@intel.com>
[ickle: Actually reference the correct bug report]
Acked-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>