diff --git a/.gitlab-ci/b2c/generate_b2c.py b/.gitlab-ci/b2c/generate_b2c.py
index 66dcebd7f1c..cbffca5e20b 100755
--- a/.gitlab-ci/b2c/generate_b2c.py
+++ b/.gitlab-ci/b2c/generate_b2c.py
@@ -42,7 +42,7 @@ values['job_volume_exclusions'] = [excl for excl in values['job_volume_exclusion
 values['working_dir'] = environ['CI_PROJECT_DIR']
 
 values['image_under_test'] = environ['IMAGE_UNDER_TEST']
-values['machine_registration_image'] = environ.get('MACHINE_REGISTRATION_IMAGE', "registry.freedesktop.org/gfx-ci/ci-tron/machine-registration:latest")
+values['machine_registration_image'] = environ['B2C_MACHINE_REGISTRATION_IMAGE']
 values['telegraf_image'] = environ.get('TELEGRAF_IMAGE', "registry.freedesktop.org/gfx-ci/ci-tron/telegraf:latest")
 
 # Pull all our images through our proxy registry
diff --git a/.gitlab-ci/test/gitlab-ci.yml b/.gitlab-ci/test/gitlab-ci.yml
index 291a9ed568e..ac42062b090 100644
--- a/.gitlab-ci/test/gitlab-ci.yml
+++ b/.gitlab-ci/test/gitlab-ci.yml
@@ -359,6 +359,7 @@ yaml-toml-shell-py-test:
     B2C_TIMEOUT_OVERALL_MINUTES: 90
     B2C_TIMEOUT_CONSOLE_ACTIVITY_RETRIES: 0
     B2C_JOB_VOLUME_EXCLUSIONS: "*.shader_cache,install/*,*/install/*,*/vkd3d-proton.cache*,vkd3d-proton.cache*,*.qpa"
+    B2C_MACHINE_REGISTRATION_IMAGE: "registry.freedesktop.org/gfx-ci/ci-tron/machine-registration:latest"
 
     # As noted in the top description, we make a distinction between the
     # container used by gitlab-runner to queue the work, and the container