diff --git a/core/Makefile b/core/Makefile
index 37e6477..f7b55e6 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -906,11 +906,9 @@
 
 INTERNAL_INIT_BOOT_IMAGE_ARGS :=
 
-INTERNAL_BOOT_HAS_RAMDISK :=
 ifneq ($(BOARD_BUILD_SYSTEM_ROOT_IMAGE),true)
   ifneq ($(BUILDING_INIT_BOOT_IMAGE),true)
     INTERNAL_BOOTIMAGE_ARGS += --ramdisk $(INSTALLED_RAMDISK_TARGET)
-    INTERNAL_BOOT_HAS_RAMDISK := true
   else
     INTERNAL_INIT_BOOT_IMAGE_ARGS += --ramdisk $(INSTALLED_RAMDISK_TARGET)
   endif
@@ -973,7 +971,6 @@
 
 INTERNAL_GKI_CERTIFICATE_ARGS :=
 INTERNAL_GKI_CERTIFICATE_DEPS :=
-INTERNAL_GENERIC_RAMDISK_BOOT_SIGNATURE :=
 ifdef BOARD_GKI_SIGNING_KEY_PATH
   ifndef BOARD_GKI_SIGNING_ALGORITHM
     $(error BOARD_GKI_SIGNING_ALGORITHM should be defined with BOARD_GKI_SIGNING_KEY_PATH)
@@ -994,13 +991,6 @@
     $(BOARD_GKI_SIGNING_KEY_PATH) \
     $(AVBTOOL)
 
-  ifdef INSTALLED_RAMDISK_TARGET
-    INTERNAL_GENERIC_RAMDISK_BOOT_SIGNATURE := \
-      $(call intermediates-dir-for,PACKAGING,generic_ramdisk)/boot_signature
-
-    $(INTERNAL_GENERIC_RAMDISK_BOOT_SIGNATURE): $(INSTALLED_RAMDISK_TARGET) $(INTERNAL_GKI_CERTIFICATE_DEPS)
-	$(call generate_generic_boot_image_certificate,$(INSTALLED_RAMDISK_TARGET),$@,generic_ramdisk,$(BOARD_AVB_INIT_BOOT_ADD_HASH_FOOTER_ARGS))
-  endif
 endif
 
 # Define these only if we are building boot
@@ -1018,14 +1008,16 @@
 # $1: boot image target
 define build_boot_board_avb_enabled
   $(eval kernel := $(call bootimage-to-kernel,$(1)))
+  $(MKBOOTIMG) --kernel $(kernel) $(INTERNAL_BOOTIMAGE_ARGS) $(INTERNAL_MKBOOTIMG_VERSION_ARGS) $(BOARD_MKBOOTIMG_ARGS) --output $(1)
   $(if $(BOARD_GKI_SIGNING_KEY_PATH), \
+    $(eval boot_signature := $(call intermediates-dir-for,PACKAGING,generic_boot)/$(notdir $(1)).boot_signature) \
     $(eval kernel_signature := $(call intermediates-dir-for,PACKAGING,generic_kernel)/$(notdir $(kernel)).boot_signature) \
+    $(call generate_generic_boot_image_certificate,$(1),$(boot_signature),boot,$(BOARD_AVB_BOOT_ADD_HASH_FOOTER_ARGS)) $(newline) \
     $(call generate_generic_boot_image_certificate,$(kernel),$(kernel_signature),generic_kernel,$(BOARD_AVB_BOOT_ADD_HASH_FOOTER_ARGS)) $(newline) \
-    $(if $(INTERNAL_BOOT_HAS_RAMDISK), \
-      cat $(INTERNAL_GENERIC_RAMDISK_BOOT_SIGNATURE) >> $(kernel_signature) $(newline)))
-  $(MKBOOTIMG) --kernel $(kernel) $(INTERNAL_BOOTIMAGE_ARGS) \
-    $(if $(BOARD_GKI_SIGNING_KEY_PATH),--boot_signature "$(kernel_signature)",$(INTERNAL_MKBOOTIMG_VERSION_ARGS)) \
-    $(BOARD_MKBOOTIMG_ARGS) --output $(1)
+    cat $(kernel_signature) >> $(boot_signature) $(newline) \
+    $(call assert-max-image-size,$(boot_signature),16 << 10) $(newline) \
+    truncate -s $$(( 16 << 10 )) $(boot_signature) $(newline) \
+    cat "$(boot_signature)" >> $(1))
   $(call assert-max-image-size,$(1),$(call get-hash-image-max-size,$(call get-bootimage-partition-size,$(1),boot)))
   $(AVBTOOL) add_hash_footer \
           --image $(1) \
@@ -1034,9 +1026,6 @@
           $(BOARD_AVB_BOOT_ADD_HASH_FOOTER_ARGS)
 endef
 
-ifdef INTERNAL_BOOT_HAS_RAMDISK
-$(INSTALLED_BOOTIMAGE_TARGET): $(INTERNAL_GENERIC_RAMDISK_BOOT_SIGNATURE)
-endif
 $(INSTALLED_BOOTIMAGE_TARGET): $(MKBOOTIMG) $(AVBTOOL) $(INTERNAL_BOOTIMAGE_FILES) $(BOARD_AVB_BOOT_KEY_PATH) $(INTERNAL_GKI_CERTIFICATE_DEPS)
 	$(call pretty,"Target boot image: $@")
 	$(call build_boot_board_avb_enabled,$@)
@@ -1141,12 +1130,9 @@
 endif
 
 ifeq ($(BOARD_AVB_ENABLE),true)
-$(INSTALLED_INIT_BOOT_IMAGE_TARGET): $(INTERNAL_GENERIC_RAMDISK_BOOT_SIGNATURE)
 $(INSTALLED_INIT_BOOT_IMAGE_TARGET): $(AVBTOOL) $(BOARD_AVB_INIT_BOOT_KEY_PATH)
 	$(call pretty,"Target init_boot image: $@")
-	$(MKBOOTIMG) $(INTERNAL_INIT_BOOT_IMAGE_ARGS) \
-	  $(if $(BOARD_GKI_SIGNING_KEY_PATH),--boot_signature "$(INTERNAL_GENERIC_RAMDISK_BOOT_SIGNATURE)",$(INTERNAL_MKBOOTIMG_VERSION_ARGS)) \
-	  $(BOARD_MKBOOTIMG_INIT_ARGS) --output "$@"
+	$(MKBOOTIMG) $(INTERNAL_INIT_BOOT_IMAGE_ARGS) $(INTERNAL_MKBOOTIMG_VERSION_ARGS) $(BOARD_MKBOOTIMG_INIT_ARGS) --output "$@"
 	$(call assert-max-image-size,$@,$(BOARD_INIT_BOOT_IMAGE_PARTITION_SIZE))
 	$(AVBTOOL) add_hash_footer \
            --image $@ \
@@ -3930,13 +3916,6 @@
     --prop com.android.build.pvmfw.security_patch:$(PVMFW_SECURITY_PATCH)
 endif
 
-# For upgrading devices without a init_boot partition, the init_boot footer args
-# should fallback to boot partition footer.
-ifndef INSTALLED_INIT_BOOT_IMAGE_TARGET
-BOARD_AVB_BOOT_ADD_HASH_FOOTER_ARGS += \
-    $(BOARD_AVB_INIT_BOOT_ADD_HASH_FOOTER_ARGS)
-endif
-
 BOOT_FOOTER_ARGS := BOARD_AVB_BOOT_ADD_HASH_FOOTER_ARGS
 INIT_BOOT_FOOTER_ARGS := BOARD_AVB_INIT_BOOT_ADD_HASH_FOOTER_ARGS
 VENDOR_BOOT_FOOTER_ARGS := BOARD_AVB_VENDOR_BOOT_ADD_HASH_FOOTER_ARGS
diff --git a/tools/releasetools/common.py b/tools/releasetools/common.py
index 107fad1..9feb8af 100644
--- a/tools/releasetools/common.py
+++ b/tools/releasetools/common.py
@@ -1405,7 +1405,7 @@
           "gki_signing_algorithm" in OPTIONS.info_dict)
 
 
-def _GenerateGkiCertificate(image, image_name, partition_name):
+def _GenerateGkiCertificate(image, image_name):
   key_path = OPTIONS.info_dict.get("gki_signing_key_path")
   algorithm = OPTIONS.info_dict.get("gki_signing_algorithm")
 
@@ -1434,8 +1434,7 @@
   if signature_args:
     cmd.extend(["--additional_avb_args", signature_args])
 
-  args = OPTIONS.info_dict.get(
-      "avb_" + partition_name + "_add_hash_footer_args", "")
+  args = OPTIONS.info_dict.get("avb_boot_add_hash_footer_args", "")
   args = args.strip()
   if args:
     cmd.extend(["--additional_avb_args", args])
@@ -1628,27 +1627,9 @@
   if args and args.strip():
     cmd.extend(shlex.split(args))
 
-  boot_signature = None
-  if _HasGkiCertificationArgs():
-    # Certify GKI images.
-    boot_signature_bytes = b''
-    if kernel_path is not None:
-      boot_signature_bytes += _GenerateGkiCertificate(
-          kernel_path, "generic_kernel", "boot")
-    if has_ramdisk:
-      boot_signature_bytes += _GenerateGkiCertificate(
-          ramdisk_img.name, "generic_ramdisk", "init_boot")
-
-    if len(boot_signature_bytes) > 0:
-      boot_signature = tempfile.NamedTemporaryFile()
-      boot_signature.write(boot_signature_bytes)
-      boot_signature.flush()
-      cmd.extend(["--boot_signature", boot_signature.name])
-  else:
-    # Certified GKI boot/init_boot image mustn't set 'mkbootimg_version_args'.
-    args = info_dict.get("mkbootimg_version_args")
-    if args and args.strip():
-      cmd.extend(shlex.split(args))
+  args = info_dict.get("mkbootimg_version_args")
+  if args and args.strip():
+    cmd.extend(shlex.split(args))
 
   if has_ramdisk:
     cmd.extend(["--ramdisk", ramdisk_img.name])
@@ -1670,6 +1651,29 @@
 
   RunAndCheckOutput(cmd)
 
+  if _HasGkiCertificationArgs():
+    if not os.path.exists(img.name):
+      raise ValueError("Cannot find GKI boot.img")
+    if kernel_path is None or not os.path.exists(kernel_path):
+      raise ValueError("Cannot find GKI kernel.img")
+
+    # Certify GKI images.
+    boot_signature_bytes = b''
+    boot_signature_bytes += _GenerateGkiCertificate(img.name, "boot")
+    boot_signature_bytes += _GenerateGkiCertificate(
+        kernel_path, "generic_kernel")
+
+    BOOT_SIGNATURE_SIZE = 16 * 1024
+    if len(boot_signature_bytes) > BOOT_SIGNATURE_SIZE:
+      raise ValueError(
+          f"GKI boot_signature size must be <= {BOOT_SIGNATURE_SIZE}")
+    boot_signature_bytes += (
+        b'\0' * (BOOT_SIGNATURE_SIZE - len(boot_signature_bytes)))
+    assert len(boot_signature_bytes) == BOOT_SIGNATURE_SIZE
+
+    with open(img.name, 'ab') as f:
+      f.write(boot_signature_bytes)
+
   if (info_dict.get("boot_signer") == "true" and
           info_dict.get("verity_key")):
     # Hard-code the path as "/boot" for two-step special recovery image (which
@@ -1730,9 +1734,6 @@
     ramdisk_img.close()
   img.close()
 
-  if boot_signature is not None:
-    boot_signature.close()
-
   return data
 
 
diff --git a/tools/releasetools/test_common.py b/tools/releasetools/test_common.py
index 7dd365f..f973263 100644
--- a/tools/releasetools/test_common.py
+++ b/tools/releasetools/test_common.py
@@ -1642,7 +1642,7 @@
     }
     test_file = tempfile.NamedTemporaryFile()
     self.assertRaises(common.ExternalError, common._GenerateGkiCertificate,
-                      test_file.name, 'generic_kernel', 'boot')
+                      test_file.name, 'generic_kernel')
 
   def test_GenerateGkiCertificate_SearchKeyPathNotFound(self):
     pubkey = 'no_testkey_gki.pem'
@@ -1662,7 +1662,7 @@
     }
     test_file = tempfile.NamedTemporaryFile()
     self.assertRaises(common.ExternalError, common._GenerateGkiCertificate,
-                      test_file.name, 'generic_kernel', 'boot')
+                      test_file.name, 'generic_kernel')
 
 class InstallRecoveryScriptFormatTest(test_utils.ReleaseToolsTestCase):
   """Checks the format of install-recovery.sh.