drm/i915: Don't underflow bestppm
We do 'bestppm - 10' in vlv_find_best_dpll() but never check whether
that might underflow. Add such a check.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index dc50775..789e6ab 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -708,7 +708,7 @@
bestppm = 0;
flag = 1;
}
- if (ppm < bestppm - 10) {
+ if (bestppm >= 10 && ppm < bestppm - 10) {
bestppm = ppm;
flag = 1;
}