diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index fce7978c4..59128a4fb 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -44,15 +44,10 @@ repos:
     hooks:
     -   id: rst-backticks
 -   repo: https://github.com/pre-commit/mirrors-mypy
-    rev: v0.711
+    rev: v0.720
     hooks:
     -   id: mypy
-        name: mypy (src)
-        files: ^src/
-        args: []
-    -   id: mypy
-        name: mypy (testing)
-        files: ^testing/
+        files: ^(src/|testing/)
         args: []
 -   repo: local
     hooks:
diff --git a/changelog/5615.removal.rst b/changelog/5615.removal.rst
new file mode 100644
index 000000000..6dd9aec1d
--- /dev/null
+++ b/changelog/5615.removal.rst
@@ -0,0 +1,7 @@
+``pytest.fail``, ``pytest.xfail`` and ``pytest.skip`` no longer support bytes for the message argument.
+
+This was supported for Python 2 where it was tempting to use ``"message"``
+instead of ``u"message"``.
+
+Python 3 code is unlikely to pass ``bytes`` to these functions. If you do,
+please decode it to an ``str`` beforehand.
diff --git a/src/_pytest/_code/code.py b/src/_pytest/_code/code.py
index 30ab01235..7d72234e7 100644
--- a/src/_pytest/_code/code.py
+++ b/src/_pytest/_code/code.py
@@ -520,7 +520,9 @@ class ExceptionInfo(Generic[_E]):
                 text = text[len(self._striptext) :]
         return text
 
-    def errisinstance(self, exc: "Type[BaseException]") -> bool:
+    def errisinstance(
+        self, exc: Union["Type[BaseException]", Tuple["Type[BaseException]", ...]]
+    ) -> bool:
         """ return True if the exception is an instance of exc """
         return isinstance(self.value, exc)
 
diff --git a/src/_pytest/outcomes.py b/src/_pytest/outcomes.py
index aaf0b35fb..a5a4e655b 100644
--- a/src/_pytest/outcomes.py
+++ b/src/_pytest/outcomes.py
@@ -24,10 +24,7 @@ class OutcomeException(BaseException):
 
     def __repr__(self) -> str:
         if self.msg:
-            val = self.msg
-            if isinstance(val, bytes):
-                val = val.decode("UTF-8", errors="replace")
-            return val
+            return self.msg
         return "<{} instance>".format(self.__class__.__name__)
 
     __str__ = __repr__
diff --git a/src/_pytest/python.py b/src/_pytest/python.py
index 8e5a02292..82ed8b9cf 100644
--- a/src/_pytest/python.py
+++ b/src/_pytest/python.py
@@ -1164,7 +1164,7 @@ def _idval(val, argname, idx, idfn, item, config):
         return str(val)
     elif isinstance(val, REGEX_TYPE):
         return ascii_escaped(val.pattern)
-    elif enum is not None and isinstance(val, enum.Enum):
+    elif isinstance(val, enum.Enum):
         return str(val)
     elif (inspect.isclass(val) or inspect.isfunction(val)) and hasattr(val, "__name__"):
         return val.__name__
diff --git a/src/_pytest/runner.py b/src/_pytest/runner.py
index edaee9725..8aae163c3 100644
--- a/src/_pytest/runner.py
+++ b/src/_pytest/runner.py
@@ -278,10 +278,7 @@ class SetupState:
         self._finalizers = {}
 
     def addfinalizer(self, finalizer, colitem):
-        """ attach a finalizer to the given colitem.
-        if colitem is None, this will add a finalizer that
-        is called at the end of teardown_all().
-        """
+        """ attach a finalizer to the given colitem. """
         assert colitem and not isinstance(colitem, tuple)
         assert callable(finalizer)
         # assert colitem in self.stack  # some unit tests don't setup stack :/
@@ -309,12 +306,9 @@ class SetupState:
 
     def _teardown_with_finalization(self, colitem):
         self._callfinalizers(colitem)
-        if hasattr(colitem, "teardown"):
-            colitem.teardown()
+        colitem.teardown()
         for colitem in self._finalizers:
-            assert (
-                colitem is None or colitem in self.stack or isinstance(colitem, tuple)
-            )
+            assert colitem in self.stack
 
     def teardown_all(self):
         while self.stack: