diff --git a/compiler/rustc_interface/src/passes.rs b/compiler/rustc_interface/src/passes.rs
index ce99b01637b04..41a4896d89e52 100644
--- a/compiler/rustc_interface/src/passes.rs
+++ b/compiler/rustc_interface/src/passes.rs
@@ -805,8 +805,8 @@ fn resolver_for_lowering_raw<'tcx>(
     );
     let krate = configure_and_expand(krate, &pre_configured_attrs, &mut resolver);
 
-    // Make sure we don't mutate the cstore from here on.
-    tcx.untracked().cstore.freeze();
+    // Don't mutate the cstore or stable crate id map from here on.
+    tcx.untracked().freeze_cstore();
 
     let ResolverOutputs {
         global_ctxt: untracked_resolutions,
diff --git a/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs b/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs
index cbd6afd68473a..be856f01a9429 100644
--- a/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs
+++ b/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs
@@ -555,15 +555,15 @@ pub(in crate::rmeta) fn provide(providers: &mut Providers) {
             )
         },
         crates: |tcx, ()| {
-            // The list of loaded crates is now frozen in query cache,
-            // so make sure cstore is not mutably accessed from here on.
-            tcx.untracked().cstore.freeze();
+            // The loaded-crate list is now frozen in the query cache; stop
+            // mutating the cstore and stable crate id map from here on.
+            tcx.untracked().freeze_cstore();
             tcx.arena.alloc_from_iter(CStore::from_tcx(tcx).iter_crate_data().map(|(cnum, _)| cnum))
         },
         used_crates: |tcx, ()| {
-            // The list of loaded crates is now frozen in query cache,
-            // so make sure cstore is not mutably accessed from here on.
-            tcx.untracked().cstore.freeze();
+            // The loaded-crate list is now frozen in the query cache; stop
+            // mutating the cstore and stable crate id map from here on.
+            tcx.untracked().freeze_cstore();
             tcx.arena.alloc_from_iter(
                 CStore::from_tcx(tcx)
                     .iter_crate_data()
diff --git a/compiler/rustc_resolve/src/lib.rs b/compiler/rustc_resolve/src/lib.rs
index 061471ccc97e0..fd60094e21558 100644
--- a/compiler/rustc_resolve/src/lib.rs
+++ b/compiler/rustc_resolve/src/lib.rs
@@ -2091,8 +2091,8 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
                 .time("resolve_postprocess", || self.cstore_mut().postprocess(self.tcx, krate));
         });
 
-        // Make sure we don't mutate the cstore from here on.
-        self.tcx.untracked().cstore.freeze();
+        // Don't mutate the cstore or stable crate id map from here on.
+        self.tcx.untracked().freeze_cstore();
     }
 
     fn traits_in_scope(
diff --git a/compiler/rustc_session/src/cstore.rs b/compiler/rustc_session/src/cstore.rs
index 39fe9c80923ec..94237132bd393 100644
--- a/compiler/rustc_session/src/cstore.rs
+++ b/compiler/rustc_session/src/cstore.rs
@@ -224,3 +224,13 @@ pub struct Untracked {
     /// The interned [StableCrateId]s.
     pub stable_crate_ids: FreezeLock<StableCrateIdMap>,
 }
+
+impl Untracked {
+    /// Freezes the cstore and, with it, the `StableCrateId` map, making reads of
+    /// both lock-free. The cstore is frozen first so any in-flight crate loading
+    /// (which writes the map) finishes before the map is frozen.
+    pub fn freeze_cstore(&self) {
+        self.cstore.freeze();
+        self.stable_crate_ids.freeze();
+    }
+}