diff --git a/src/intel/compiler/brw_fs.cpp b/src/intel/compiler/brw_fs.cpp
index 359262ca489..46e346ec984 100644
--- a/src/intel/compiler/brw_fs.cpp
+++ b/src/intel/compiler/brw_fs.cpp
@@ -9452,6 +9452,9 @@ brw_compute_flat_inputs(struct brw_wm_prog_data *prog_data,
    prog_data->flat_inputs = 0;
 
    nir_foreach_shader_in_variable(var, shader) {
+      if (var->data.per_primitive)
+         continue;
+
       unsigned slots = glsl_count_attribute_slots(var->type, false);
       for (unsigned s = 0; s < slots; s++) {
          int input_index = prog_data->urb_setup[var->data.location + s];