diff --git a/build_image b/build_image
index aa59531..fc46765 100755
--- a/build_image
+++ b/build_image
@@ -27,7 +27,7 @@
   "Directory in which to place image result directories (named by version)"
 DEFINE_string disk_layout "default" \
   "The disk layout type to use for this image."
-DEFINE_string enable_serial "" \
+DEFINE_string enable_serial "ttyMSM0" \
   "Enable serial port for printks. Example values: ttyS0"
 DEFINE_integer loglevel 7 \
   "The loglevel to add to the kernel command line."
@@ -133,18 +133,13 @@
   export USE="${USE} fbconsole vtconsole factory_shim_ramfs tpm i2cdev vfat"
 fi
 
-if should_build_image ${CHROMEOS_TEST_IMAGE_NAME}; then
+if should_build_image ${CHROMEOS_FACTORY_TEST_IMAGE_NAME} ||
+   should_build_image ${CHROMEOS_TEST_IMAGE_NAME}; then
   # Disable module restrictions on factory test image to allow for
   # external third party drivers in /usr/local.
   FLAGS_boot_args="${FLAGS_boot_args} lsm.module_locking=0"
 fi
 
-if should_build_image "${CHROMEOS_FACTORY_SHIM_NAME}" ||
-   should_build_image "${CHROMEOS_TEST_IMAGE_NAME}"; then
-  # Enable serial if not specified.
-  [ -n "${FLAGS_enable_serial}" ] || FLAGS_enable_serial="ttyMSM0"
-fi
-
 # TODO: </prebuild hook>
 
 # If we are creating a developer image, also create a pristine image with a
diff --git a/security_test_image b/security_test_image
index e2b1ca5..adcec11 100755
--- a/security_test_image
+++ b/security_test_image
@@ -112,7 +112,6 @@
 sec_checks=(
   no_nonrelease_files
   sane_lsb-release
-  secure_kernelparams
 )
 for check in "${sec_checks[@]}"; do
   run_check "${check}" "${check}"