The display param duplication deviates from the original param duplication in that it converts NULL params to to allocated empty strings. This works for the vbt_firmware parameter, but not for dmc_firmware_path, the user of which interprets NULL and the empty string as distinct values. Specifically, the empty dmc_firmware_path leads to DMC and PM being disabled.
Just remove the NULL check and pass it to kstrdup(), which safely returns NULL for NULL input.
Fixes: 8015bee0bfec ("drm/i915/display: Add framework to add parameters specific to display") Fixes: 0d82a0d6f556 ("drm/i915/display: move dmc_firmware_path to display params") Cc: Jouni Högander jouni.hogander@intel.com Cc: Luca Coelho luciano.coelho@intel.com Cc: stable@vger.kernel.org # v6.8+ Signed-off-by: Jani Nikula jani.nikula@intel.com --- drivers/gpu/drm/i915/display/intel_display_params.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_display_params.c b/drivers/gpu/drm/i915/display/intel_display_params.c index c8e3d6892e23..49c6b42077dc 100644 --- a/drivers/gpu/drm/i915/display/intel_display_params.c +++ b/drivers/gpu/drm/i915/display/intel_display_params.c @@ -176,9 +176,9 @@ void intel_display_params_dump(struct drm_i915_private *i915, struct drm_printer #undef PRINT }
-__maybe_unused static void _param_dup_charp(char **valp) +static void _param_dup_charp(char **valp) { - *valp = kstrdup(*valp ? *valp : "", GFP_ATOMIC); + *valp = kstrdup(*valp, GFP_ATOMIC); }
__maybe_unused static void _param_nop(void *valp)