diff --git a/src/backends/native/meta-kms-device-private.h b/src/backends/native/meta-kms-device-private.h
index 1660b9707..f40e9e979 100644
--- a/src/backends/native/meta-kms-device-private.h
+++ b/src/backends/native/meta-kms-device-private.h
@@ -23,6 +23,7 @@
 #include "backends/native/meta-kms-types.h"
 #include "backends/native/meta-kms-update-private.h"
 
+META_EXPORT_TEST
 MetaKmsImplDevice * meta_kms_device_get_impl_device (MetaKmsDevice *device);
 
 MetaKmsResourceChanges meta_kms_device_update_states_in_impl (MetaKmsDevice *device,
diff --git a/src/backends/native/meta-kms-device.c b/src/backends/native/meta-kms-device.c
index 9948dd160..afc264dfe 100644
--- a/src/backends/native/meta-kms-device.c
+++ b/src/backends/native/meta-kms-device.c
@@ -371,17 +371,51 @@ meta_create_kms_impl_device (MetaKmsDevice      *device,
 {
   meta_assert_in_kms_impl (meta_kms_impl_get_kms (impl));
 
-  if (flags & META_KMS_DEVICE_FLAG_NO_MODE_SETTING)
+  const char *env_kms_mode;
+  enum {
+    KMS_MODE_AUTO,
+    KMS_MODE_ATOMIC,
+    KMS_MODE_SIMPLE,
+    KMS_MODE_HEADLESS,
+  } kms_mode;
+
+  meta_assert_in_kms_impl (meta_kms_impl_get_kms (impl));
+
+  env_kms_mode = g_getenv ("MUTTER_DEBUG_FORCE_KMS_MODE");
+  if (env_kms_mode)
     {
-      return g_initable_new (META_TYPE_KMS_IMPL_DEVICE_DUMMY,
-                             NULL, error,
-                             "device", device,
-                             "impl", impl,
-                             "path", path,
-                             "flags", flags,
-                             NULL);
+      if (g_strcmp0 (env_kms_mode, "auto") == 0)
+        {
+          kms_mode = KMS_MODE_AUTO;
+        }
+      else if (g_strcmp0 (env_kms_mode, "atomic") == 0)
+        {
+          kms_mode = KMS_MODE_ATOMIC;
+        }
+      else if (g_strcmp0 (env_kms_mode, "simple") == 0)
+        {
+          kms_mode = KMS_MODE_SIMPLE;
+        }
+      else if (g_strcmp0 (env_kms_mode, "headless") == 0)
+        {
+          kms_mode = KMS_MODE_HEADLESS;
+        }
+      else
+        {
+          g_warning ("Attempted to force invalid mode setting mode '%s",
+                     env_kms_mode);
+          kms_mode = KMS_MODE_AUTO;
+        }
     }
   else
+    {
+      if (flags & META_KMS_DEVICE_FLAG_NO_MODE_SETTING)
+        kms_mode = KMS_MODE_HEADLESS;
+      else
+        kms_mode = KMS_MODE_AUTO;
+    }
+
+  if (kms_mode == KMS_MODE_AUTO)
     {
       GType impl_device_types[] = {
         META_TYPE_KMS_IMPL_DEVICE_ATOMIC,
@@ -417,6 +451,32 @@ meta_create_kms_impl_device (MetaKmsDevice      *device,
 
       return NULL;
     }
+  else
+    {
+      GType type;
+
+      switch (kms_mode)
+        {
+        case KMS_MODE_ATOMIC:
+          type = META_TYPE_KMS_IMPL_DEVICE_ATOMIC;
+          break;
+        case KMS_MODE_SIMPLE:
+          type = META_TYPE_KMS_IMPL_DEVICE_SIMPLE;
+          break;
+        case KMS_MODE_HEADLESS:
+          type = META_TYPE_KMS_IMPL_DEVICE_DUMMY;
+          break;
+        default:
+          g_assert_not_reached ();
+        };
+
+      return g_initable_new (type, NULL, error,
+                             "device", device,
+                             "impl", impl,
+                             "path", path,
+                             "flags", flags,
+                             NULL);
+    }
 }
 
 static gpointer
diff --git a/src/backends/native/meta-kms-impl-device-atomic.c b/src/backends/native/meta-kms-impl-device-atomic.c
index 36cf6c39d..b1925f984 100644
--- a/src/backends/native/meta-kms-impl-device-atomic.c
+++ b/src/backends/native/meta-kms-impl-device-atomic.c
@@ -1212,15 +1212,6 @@ meta_kms_impl_device_atomic_initable_init (GInitable     *initable,
                                            GError       **error)
 {
   MetaKmsImplDevice *impl_device = META_KMS_IMPL_DEVICE (initable);
-  const char *atomic_kms_enable_env;
-
-  atomic_kms_enable_env = getenv ("MUTTER_DEBUG_ENABLE_ATOMIC_KMS");
-  if (atomic_kms_enable_env && g_strcmp0 (atomic_kms_enable_env, "1") != 0)
-    {
-      g_set_error (error, META_KMS_ERROR, META_KMS_ERROR_USER_INHIBITED,
-                   "Atomic mode setting disable via env var");
-      return FALSE;
-    }
 
   if (!initable_parent_iface->init (initable, cancellable, error))
     return FALSE;
diff --git a/src/backends/native/meta-kms-impl-device-atomic.h b/src/backends/native/meta-kms-impl-device-atomic.h
index 74658797c..99aa066db 100644
--- a/src/backends/native/meta-kms-impl-device-atomic.h
+++ b/src/backends/native/meta-kms-impl-device-atomic.h
@@ -23,6 +23,7 @@
 #include "backends/native/meta-kms-impl-device.h"
 
 #define META_TYPE_KMS_IMPL_DEVICE_ATOMIC (meta_kms_impl_device_atomic_get_type ())
+META_EXPORT_TEST
 G_DECLARE_FINAL_TYPE (MetaKmsImplDeviceAtomic, meta_kms_impl_device_atomic,
                       META, KMS_IMPL_DEVICE_ATOMIC, MetaKmsImplDevice)
 
diff --git a/src/backends/native/meta-kms-impl-device-simple.h b/src/backends/native/meta-kms-impl-device-simple.h
index 7be5f0a83..aeea434fd 100644
--- a/src/backends/native/meta-kms-impl-device-simple.h
+++ b/src/backends/native/meta-kms-impl-device-simple.h
@@ -23,6 +23,7 @@
 #include "backends/native/meta-kms-impl-device.h"
 
 #define META_TYPE_KMS_IMPL_DEVICE_SIMPLE (meta_kms_impl_device_simple_get_type ())
+META_EXPORT_TEST
 G_DECLARE_FINAL_TYPE (MetaKmsImplDeviceSimple, meta_kms_impl_device_simple,
                       META, KMS_IMPL_DEVICE_SIMPLE, MetaKmsImplDevice)
 
diff --git a/src/tests/kvm/meson.build b/src/tests/kvm/meson.build
index bdd74ff54..17aaff1f5 100644
--- a/src/tests/kvm/meson.build
+++ b/src/tests/kvm/meson.build
@@ -27,20 +27,20 @@ endif
 
 virtme_run = find_program('virtme-run.sh')
 
-vm_env_entries = []
-foreach name, value: test_env_variables
-  vm_env_entries += ['@0@=@1@'.format(name, value)]
-endforeach
-vm_env = ' '.join(vm_env_entries)
-
 foreach test_case: privileged_tests
+  vm_env_entries = []
+  foreach name, value: test_case['variables']
+    vm_env_entries += ['@0@=@1@'.format(name, value)]
+  endforeach
+  vm_env = ' '.join(vm_env_entries)
+
   test('kvm-' + test_case['name'], virtme_run,
     suite: ['core', 'mutter/kvm', 'mutter/kvm/' + test_case['suite']],
     depends: [
       kernel_image_target,
     ],
     workdir: mutter_srcdir,
-    env: test_env,
+    env: test_case['env'],
     args: [
       kernel_image_path,
       meta_dbus_runner.full_path(),
diff --git a/src/tests/kvm/virtme-run.sh b/src/tests/kvm/virtme-run.sh
index 006209387..7d2929bb1 100755
--- a/src/tests/kvm/virtme-run.sh
+++ b/src/tests/kvm/virtme-run.sh
@@ -20,6 +20,10 @@ XDG_DATA_DIRS=$XDG_DATA_DIRS \
 $VM_ENV \
 "
 
+if [ ! -v $MUTTER_DEBUG_FORCE_KMS_MODE ]; then
+  VIRTME_ENV="$VIRTME_ENV MUTTER_DEBUG_FORCE_KMS_MODE=$MUTTER_DEBUG_FORCE_KMS_MODE"
+fi
+
 if [[ "$(stat -c '%t:%T' -L /proc/$$/fd/0)" == "0:0" ]]; then
   mkfifo $XDG_RUNTIME_DIR/fake-stdin.$$
   exec 0<> $XDG_RUNTIME_DIR/fake-stdin.$$
diff --git a/src/tests/meson.build b/src/tests/meson.build
index 6d2105332..33f413dbb 100644
--- a/src/tests/meson.build
+++ b/src/tests/meson.build
@@ -263,8 +263,40 @@ if have_native_tests
     },
   ]
 
-  # Privileged tests
-  privileged_test_cases += [
+  # KMS tests
+  kms_test_variants = []
+  kms_atomic_variables = {'MUTTER_DEBUG_FORCE_KMS_MODE': 'atomic'}
+  kms_simple_variables = {'MUTTER_DEBUG_FORCE_KMS_MODE': 'simple'}
+  kms_variants = [
+    ['atomic', kms_atomic_variables],
+    ['simple', kms_simple_variables],
+  ]
+  foreach variant: kms_variants
+    name = variant[0]
+    variables = variant[1]
+    suffix = '-@0@'.format(name)
+
+    kms_test_env_variables = test_env_variables + variables
+    kms_test_variants += [[suffix, kms_test_env_variables]]
+  endforeach
+
+  kms_test_cases = [
+    {
+      'name': 'kms-force-atomic-sanity',
+      'suite': 'backends/native/kms',
+      'sources': [
+        'native-kms-force-atomic-sanity.c',
+      ],
+      'variants': [['', test_env_variables + kms_atomic_variables]],
+    },
+    {
+      'name': 'kms-force-simple-sanity',
+      'suite': 'backends/native/kms',
+      'sources': [
+        'native-kms-force-simple-sanity.c',
+      ],
+      'variants': [['', test_env_variables + kms_simple_variables]],
+    },
     {
       'name': 'kms-render',
       'suite': 'backends/native/kms',
@@ -272,6 +304,7 @@ if have_native_tests
         'native-kms-render.c',
         wayland_test_utils,
       ],
+      'variants': kms_test_variants,
     },
     {
       'name': 'kms-device',
@@ -281,6 +314,7 @@ if have_native_tests
         'meta-kms-test-utils.h',
         'native-kms-device.c',
       ],
+      'variants': kms_test_variants,
     },
     {
       'name': 'kms-update',
@@ -290,9 +324,12 @@ if have_native_tests
         'meta-kms-test-utils.h',
         'native-kms-updates.c',
       ],
+      'variants': kms_test_variants,
     },
   ]
 
+  privileged_test_cases += kms_test_cases
+
   # Wayland tests
   test_cases += [
     {
@@ -379,6 +416,12 @@ endforeach
 if have_kvm_tests or have_tty_tests
   privileged_tests = []
   foreach test_case: privileged_test_cases
+    if test_case.has_key('variants')
+      variants = test_case['variants']
+    else
+      variants = [['', test_env_variables, []]]
+    endif
+
     test_executable = executable('mutter-' + test_case['name'],
       sources: test_case['sources'],
       include_directories: tests_includes,
@@ -390,13 +433,22 @@ if have_kvm_tests or have_tty_tests
       install: have_installed_tests,
       install_dir: mutter_installed_tests_libexecdir,
     )
-    privileged_tests += [
-      {
-        'name': test_case['name'],
-        'suite': test_case['suite'],
-        'executable': test_executable,
-      },
-    ]
+
+    foreach variant: variants
+      variant_env = environment()
+      foreach name, value: variant[1]
+        variant_env.set(name, value)
+      endforeach
+      privileged_tests += [
+        {
+          'name': '@0@@1@'.format(test_case['name'], variant[0]),
+          'suite': test_case['suite'],
+          'executable': test_executable,
+          'variables': variant[1],
+          'env': variant_env,
+        },
+      ]
+    endforeach
   endforeach
 
   if have_kvm_tests
@@ -407,7 +459,7 @@ if have_kvm_tests or have_tty_tests
     foreach test_case: privileged_tests
       test('tty-' + test_case['name'], test_case['executable'],
         suite: ['core', 'mutter/tty', 'mutter/tty/' + test_case['suite']],
-        env: test_env,
+        env: test_case['env'],
         is_parallel: false,
         timeout: 60,
       )
diff --git a/src/tests/native-kms-force-atomic-sanity.c b/src/tests/native-kms-force-atomic-sanity.c
new file mode 100644
index 000000000..fe8d3dbfb
--- /dev/null
+++ b/src/tests/native-kms-force-atomic-sanity.c
@@ -0,0 +1,75 @@
+/*
+ * Copyright (C) 2022 Red Hat Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ *
+ */
+
+#include "config.h"
+
+#include "backends/native/meta-backend-native.h"
+#include "backends/native/meta-kms.h"
+#include "backends/native/meta-kms-device.h"
+#include "backends/native/meta-kms-device-private.h"
+#include "backends/native/meta-kms-impl-device-atomic.h"
+#include "meta-test/meta-context-test.h"
+
+static MetaContext *test_context;
+
+static void
+meta_test_kms_force_atomic_sanity (void)
+{
+  MetaBackend *backend = meta_context_get_backend (test_context);
+  MetaKms *kms = meta_backend_native_get_kms (META_BACKEND_NATIVE (backend));
+  GList *l;
+
+  g_assert_nonnull (meta_kms_get_devices (kms));
+
+  for (l = meta_kms_get_devices (kms); l; l = l->next)
+    {
+      MetaKmsDevice *device = META_KMS_DEVICE (l->data);
+      MetaKmsImplDevice *impl_device;
+
+      impl_device = meta_kms_device_get_impl_device (device);
+      g_assert_true (META_IS_KMS_IMPL_DEVICE_ATOMIC (impl_device));
+    }
+}
+
+static void
+init_tests (void)
+{
+  g_test_add_func ("/backends/native/kms/force-atomic-sanity",
+                   meta_test_kms_force_atomic_sanity);
+}
+
+int
+main (int    argc,
+      char **argv)
+{
+  g_autoptr (MetaContext) context = NULL;
+  g_autoptr (GError) error = NULL;
+
+  context = meta_create_test_context (META_CONTEXT_TEST_TYPE_VKMS,
+                                      META_CONTEXT_TEST_FLAG_NO_X11);
+  g_assert (meta_context_configure (context, &argc, &argv, NULL));
+
+  test_context = context;
+
+  init_tests ();
+
+  return meta_context_test_run_tests (META_CONTEXT_TEST (context),
+                                      META_TEST_RUN_FLAG_CAN_SKIP);
+}
diff --git a/src/tests/native-kms-force-simple-sanity.c b/src/tests/native-kms-force-simple-sanity.c
new file mode 100644
index 000000000..e1f6a69b0
--- /dev/null
+++ b/src/tests/native-kms-force-simple-sanity.c
@@ -0,0 +1,75 @@
+/*
+ * Copyright (C) 2022 Red Hat Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ *
+ */
+
+#include "config.h"
+
+#include "backends/native/meta-backend-native.h"
+#include "backends/native/meta-kms.h"
+#include "backends/native/meta-kms-device.h"
+#include "backends/native/meta-kms-device-private.h"
+#include "backends/native/meta-kms-impl-device-simple.h"
+#include "meta-test/meta-context-test.h"
+
+static MetaContext *test_context;
+
+static void
+meta_test_kms_force_simple_sanity (void)
+{
+  MetaBackend *backend = meta_context_get_backend (test_context);
+  MetaKms *kms = meta_backend_native_get_kms (META_BACKEND_NATIVE (backend));
+  GList *l;
+
+  g_assert_nonnull (meta_kms_get_devices (kms));
+
+  for (l = meta_kms_get_devices (kms); l; l = l->next)
+    {
+      MetaKmsDevice *device = META_KMS_DEVICE (l->data);
+      MetaKmsImplDevice *impl_device;
+
+      impl_device = meta_kms_device_get_impl_device (device);
+      g_assert_true (META_IS_KMS_IMPL_DEVICE_SIMPLE (impl_device));
+    }
+}
+
+static void
+init_tests (void)
+{
+  g_test_add_func ("/backends/native/kms/force-simple-sanity",
+                   meta_test_kms_force_simple_sanity);
+}
+
+int
+main (int    argc,
+      char **argv)
+{
+  g_autoptr (MetaContext) context = NULL;
+  g_autoptr (GError) error = NULL;
+
+  context = meta_create_test_context (META_CONTEXT_TEST_TYPE_VKMS,
+                                      META_CONTEXT_TEST_FLAG_NO_X11);
+  g_assert (meta_context_configure (context, &argc, &argv, NULL));
+
+  test_context = context;
+
+  init_tests ();
+
+  return meta_context_test_run_tests (META_CONTEXT_TEST (context),
+                                      META_TEST_RUN_FLAG_CAN_SKIP);
+}