Commit a40e718d authored by Jani Nikula's avatar Jani Nikula
Browse files

drm/i915/dp: Fix potential infinite loop in 128b/132b SST 



Passing 0 as the step only works when there are other reasons to break
out of the BPP loop in intel_dp_mtp_tu_compute_config(). Otherwise, an
infinite loop might occur. Fix it by explicitly checking for 0 step.

Fixes: ef0a0757 ("drm/i915/dp: compute config for 128b/132b SST w/o DSC")
Reported-by: default avatarImre Deak <imre.deak@intel.com>
Closes: https://lore.kernel.org/r/Z6I0knh2Kt5T0JrT@ideak-desk.fi.intel.com


Reviewed-by: default avatarImre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250204154925.3001781-1-jani.nikula@intel.com


Signed-off-by: default avatarJani Nikula <jani.nikula@intel.com>
parent b5ee4c28

drivers/gpu/drm/i915/display/intel_dp_mst.c

+4 −0
Original line number Diff line number Diff line
@@ -378,6 +378,10 @@ int intel_dp_mtp_tu_compute_config(struct intel_dp *intel_dp, 


			break;

		}



		/* Allow using zero step to indicate one try */

		if (!bpp_step_x16)

			break;

	}



	if (slots < 0) {