diff --git a/cumulus/pallets/parachain-system/src/lib.rs b/cumulus/pallets/parachain-system/src/lib.rs
index bac1ee28a7ca..5afab5d49493 100644
--- a/cumulus/pallets/parachain-system/src/lib.rs
+++ b/cumulus/pallets/parachain-system/src/lib.rs
@@ -526,8 +526,11 @@ pub mod pallet {
 		/// As a side effect, this function upgrades the current validation function
 		/// if the appropriate time has come.
 		#[pallet::call_index(0)]
-		#[pallet::weight((0, DispatchClass::Mandatory))]
-		// TODO: This weight should be corrected.
+		#[pallet::weight((<T as frame_system::Config>::BlockWeights::get().max_block, DispatchClass::Mandatory))]
+		// It makes no sense to have a weight hint for mandatory inherents, because like hooks they must be
+		// executed regardless of the weight they consume. We just need to be sure that:
+		// - The returned `actual_weight` field is always Some.
+		// - The weight hint is always greather than the returned `actual_weight`.
 		pub fn set_validation_data(
 			origin: OriginFor<T>,
 			data: ParachainInherentData,