diff --git a/eden/scm/edenscmnative/bindings/modules/pyerror/src/lib.rs b/eden/scm/edenscmnative/bindings/modules/pyerror/src/lib.rs
index 50151ecbfe..16568f01ab 100644
--- a/eden/scm/edenscmnative/bindings/modules/pyerror/src/lib.rs
+++ b/eden/scm/edenscmnative/bindings/modules/pyerror/src/lib.rs
@@ -36,13 +36,25 @@ pub fn init_module(py: Python, package: &str) -> PyResult<PyModule> {
 fn register_error_handlers() {
     fn specific_error_handler(py: Python, e: &error::Error) -> Option<PyErr> {
         if let Some(e) = e.downcast_ref::<indexedlog::Error>() {
-            Some(PyErr::new::<IndexedLogError, _>(py, e.to_string()))
+            Some(PyErr::new::<IndexedLogError, _>(
+                py,
+                cpython_ext::Str::from(e.to_string()),
+            ))
         } else if let Some(e) = e.downcast_ref::<metalog::Error>() {
-            Some(PyErr::new::<MetaLogError, _>(py, e.to_string()))
+            Some(PyErr::new::<MetaLogError, _>(
+                py,
+                cpython_ext::Str::from(e.to_string()),
+            ))
         } else if let Some(e) = e.downcast_ref::<revisionstore::Error>() {
-            Some(PyErr::new::<RevisionstoreError, _>(py, e.to_string()))
+            Some(PyErr::new::<RevisionstoreError, _>(
+                py,
+                cpython_ext::Str::from(e.to_string()),
+            ))
         } else if let Some(e) = e.downcast_ref::<cpython_ext::Error>() {
-            Some(PyErr::new::<NonUTF8Path, _>(py, e.to_string()))
+            Some(PyErr::new::<NonUTF8Path, _>(
+                py,
+                cpython_ext::Str::from(e.to_string()),
+            ))
         } else {
             None
         }
diff --git a/eden/scm/tests/test-adding-invalid-utf8-t.py b/eden/scm/tests/test-adding-invalid-utf8-t.py
index 42dcc7539d..0ad3ea422d 100644
--- a/eden/scm/tests/test-adding-invalid-utf8-t.py
+++ b/eden/scm/tests/test-adding-invalid-utf8-t.py
@@ -1,3 +1,4 @@
+# coding=utf-8
 # Copyright (c) Facebook, Inc. and its affiliates.
 #
 # This software may be used and distributed according to the terms of the
@@ -16,10 +17,15 @@ feature.require(["no-windows", "no-osx"])
 # Test that trying to add invalid utf8 files to the repository will fail.
 
 sh % "hg init"
-open("invalid\x80utf8", "w").write("test")
+open("\x9d\xc8\xac\xde\xa1\xee", "w").write("test")
+
+sh % "hg status" == r"""
+    abort: "\x9DȬޡ\xEE" is not a valid UTF-8 path
+    [255]"""
+
 sh % "hg addremove" == r"""
-    abort: "invalid\x80utf8" is not a valid UTF-8 path
+    abort: "\x9DȬޡ\xEE" is not a valid UTF-8 path
     [255]"""
 sh % "hg commit -m 'adding a filename that is invalid utf8'" == r"""
-    abort: "invalid\x80utf8" is not a valid UTF-8 path
+    abort: "\x9DȬޡ\xEE" is not a valid UTF-8 path
     [255]"""