diff --git a/core/base_rules.mk b/core/base_rules.mk
index d5055d481..94aa1e4a9 100644
--- a/core/base_rules.mk
+++ b/core/base_rules.mk
@@ -760,6 +760,18 @@ endif  # LOCAL_PRESUBMIT_DISABLED
 ## Register with ALL_MODULES
 ###########################################################
 
+ifeq ($(filter $(my_register_name),$(ALL_MODULES)),)
+    # These keys are no longer used, they've been replaced by keys that specify
+    # target/host/host_cross (REQUIRED_FROM_TARGET / REQUIRED_FROM_HOST) and similar.
+    #
+    # Marking them obsolete to ensure that anyone using these internal variables looks for
+    # alternates.
+    $(KATI_obsolete_var ALL_MODULES.$(my_register_name).REQUIRED)
+    $(KATI_obsolete_var ALL_MODULES.$(my_register_name).EXPLICITLY_REQUIRED)
+    $(KATI_obsolete_var ALL_MODULES.$(my_register_name).HOST_REQUIRED)
+    $(KATI_obsolete_var ALL_MODULES.$(my_register_name).TARGET_REQUIRED)
+endif
+
 ALL_MODULES += $(my_register_name)
 
 # Don't use += on subvars, or else they'll end up being
@@ -820,17 +832,42 @@ ifneq ($(LOCAL_USE_VNDK),)
   endif
 endif
 
-ALL_MODULES.$(my_register_name).REQUIRED := \
-    $(strip $(ALL_MODULES.$(my_register_name).REQUIRED) $(my_required_modules))
-ALL_MODULES.$(my_register_name).EXPLICITLY_REQUIRED := \
-    $(strip $(ALL_MODULES.$(my_register_name).EXPLICITLY_REQUIRED)\
-        $(my_required_modules))
-ALL_MODULES.$(my_register_name).TARGET_REQUIRED := \
-    $(strip $(ALL_MODULES.$(my_register_name).TARGET_REQUIRED)\
-        $(LOCAL_TARGET_REQUIRED_MODULES))
-ALL_MODULES.$(my_register_name).HOST_REQUIRED := \
-    $(strip $(ALL_MODULES.$(my_register_name).HOST_REQUIRED)\
-        $(LOCAL_HOST_REQUIRED_MODULES))
+ifdef LOCAL_IS_HOST_MODULE
+    ifneq ($(my_host_cross),true)
+        ALL_MODULES.$(my_register_name).REQUIRED_FROM_HOST := \
+            $(strip $(ALL_MODULES.$(my_register_name).REQUIRED_FROM_HOST) $(my_required_modules))
+        ALL_MODULES.$(my_register_name).EXPLICITLY_REQUIRED_FROM_HOST := \
+            $(strip $(ALL_MODULES.$(my_register_name).EXPLICITLY_REQUIRED_FROM_HOST)\
+                $(my_required_modules))
+        ALL_MODULES.$(my_register_name).TARGET_REQUIRED_FROM_HOST := \
+            $(strip $(ALL_MODULES.$(my_register_name).TARGET_REQUIRED_FROM_HOST)\
+                $(LOCAL_TARGET_REQUIRED_MODULES))
+    else
+        ALL_MODULES.$(my_register_name).REQUIRED_FROM_HOST_CROSS := \
+            $(strip $(ALL_MODULES.$(my_register_name).REQUIRED_FROM_HOST_CROSS) $(my_required_modules))
+        ALL_MODULES.$(my_register_name).EXPLICITLY_REQUIRED_FROM_HOST_CROSS := \
+            $(strip $(ALL_MODULES.$(my_register_name).EXPLICITLY_REQUIRED_FROM_HOST_CROSS)\
+                $(my_required_modules))
+        ifdef LOCAL_TARGET_REQUIRED_MODULES
+            $(call pretty-error,LOCAL_TARGET_REQUIRED_MODULES may not be used from host_cross modules)
+        endif
+    endif
+    ifdef LOCAL_HOST_REQUIRED_MODULES
+        $(call pretty-error,LOCAL_HOST_REQUIRED_MODULES may not be used from host modules. Use LOCAL_REQUIRED_MODULES instead)
+    endif
+else
+    ALL_MODULES.$(my_register_name).REQUIRED_FROM_TARGET := \
+        $(strip $(ALL_MODULES.$(my_register_name).REQUIRED_FROM_TARGET) $(my_required_modules))
+    ALL_MODULES.$(my_register_name).EXPLICITLY_REQUIRED_FROM_TARGET := \
+        $(strip $(ALL_MODULES.$(my_register_name).EXPLICITLY_REQUIRED_FROM_TARGET)\
+            $(my_required_modules))
+    ALL_MODULES.$(my_register_name).HOST_REQUIRED_FROM_TARGET := \
+        $(strip $(ALL_MODULES.$(my_register_name).HOST_REQUIRED_FROM_TARGET)\
+            $(LOCAL_HOST_REQUIRED_MODULES))
+    ifdef LOCAL_TARGET_REQUIRED_MODULES
+        $(call pretty-error,LOCAL_TARGET_REQUIRED_MODULES may not be used from target modules. Use LOCAL_REQUIRED_MODULES instead)
+    endif
+endif
 ALL_MODULES.$(my_register_name).EVENT_LOG_TAGS := \
     $(ALL_MODULES.$(my_register_name).EVENT_LOG_TAGS) $(event_log_tags)
 ALL_MODULES.$(my_register_name).MAKEFILE := \
diff --git a/core/definitions.mk b/core/definitions.mk
index 205a05591..59aeb1663 100644
--- a/core/definitions.mk
+++ b/core/definitions.mk
@@ -3334,7 +3334,7 @@ $(foreach source,$(ENFORCE_RRO_SOURCES), \
   $(eval enforce_rro_source_overlays := $(subst :, ,$(word 5,$(_o)))) \
   $(eval enforce_rro_partition := $(word 6,$(_o))) \
   $(eval include $(BUILD_SYSTEM)/generate_enforce_rro.mk) \
-  $(eval ALL_MODULES.$$(enforce_rro_source_module).REQUIRED += $$(LOCAL_PACKAGE_NAME)) \
+  $(eval ALL_MODULES.$$(enforce_rro_source_module).REQUIRED_FROM_TARGET += $$(LOCAL_PACKAGE_NAME)) \
 )
 endef
 
diff --git a/core/main.mk b/core/main.mk
index 25dd24bcd..3ff2fcdfc 100644
--- a/core/main.mk
+++ b/core/main.mk
@@ -595,12 +595,10 @@ endef
 # Otherwise if the module is an executable or shared library,
 #   the required modules must be 64-bit;
 #   otherwise we require both 64-bit and 32-bit variant, if one exists.
-define select-bitness-of-required-modules
+define target-select-bitness-of-required-modules
 $(foreach m,$(ALL_MODULES),\
-  $(eval r := $(ALL_MODULES.$(m).REQUIRED))\
+  $(eval r := $(ALL_MODULES.$(m).REQUIRED_FROM_TARGET))\
   $(if $(r),\
-    $(if $(ALL_MODULES.$(m).FOR_HOST_CROSS),\
-      $(eval r := $(addprefix host_cross_,$(r))))\
     $(if $(ALL_MODULES.$(m).FOR_2ND_ARCH),\
       $(eval r_r := $(call get-32-bit-modules-if-we-can,$(r))),\
       $(if $(filter EXECUTABLES SHARED_LIBRARIES NATIVE_TESTS,$(ALL_MODULES.$(m).CLASS)),\
@@ -608,11 +606,47 @@ $(foreach m,$(ALL_MODULES),\
         $(eval r_r := $(r) $(call get-32-bit-modules,$(r)))\
        )\
      )\
-     $(eval ALL_MODULES.$(m).REQUIRED := $(strip $(r_r)))\
+     $(eval ALL_MODULES.$(m).REQUIRED_FROM_TARGET := $(strip $(r_r)))\
   )\
 )
 endef
-$(call select-bitness-of-required-modules)
+$(call target-select-bitness-of-required-modules)
+
+define host-select-bitness-of-required-modules
+$(foreach m,$(ALL_MODULES),\
+  $(eval r := $(ALL_MODULES.$(m).REQUIRED_FROM_HOST))\
+  $(if $(r),\
+    $(if $(ALL_MODULES.$(m).FOR_2ND_ARCH),\
+      $(eval r_r := $(call get-host-32-bit-modules-if-we-can,$(r))),\
+      $(if $(filter EXECUTABLES SHARED_LIBRARIES NATIVE_TESTS,$(ALL_MODULES.$(m).CLASS)),\
+        $(eval r_r := $(r)),\
+        $(eval r_r := $(r) $(call get-host-32-bit-modules,$(r)))\
+       )\
+     )\
+     $(eval ALL_MODULES.$(m).REQUIRED_FROM_HOST := $(strip $(r_r)))\
+  )\
+)
+endef
+$(call host-select-bitness-of-required-modules)
+
+define host-cross-select-bitness-of-required-modules
+$(foreach m,$(ALL_MODULES),\
+  $(eval r := $(ALL_MODULES.$(m).REQUIRED_FROM_HOST_CROSS))\
+  $(if $(r),\
+    $(if $(ALL_MODULES.$(m).FOR_HOST_CROSS),,$(error Only expected REQUIRED_FROM_HOST_CROSS on FOR_HOST_CROSS modules - $(m)))\
+    $(eval r := $(addprefix host_cross_,$(r)))\
+    $(if $(ALL_MODULES.$(m).FOR_2ND_ARCH),\
+      $(eval r_r := $(call get-host-32-bit-modules-if-we-can,$(r))),\
+      $(if $(filter EXECUTABLES SHARED_LIBRARIES NATIVE_TESTS,$(ALL_MODULES.$(m).CLASS)),\
+        $(eval r_r := $(r)),\
+        $(eval r_r := $(r) $(call get-host-32-bit-modules,$(r)))\
+       )\
+     )\
+     $(eval ALL_MODULES.$(m).REQUIRED_FROM_HOST_CROSS := $(strip $(r_r)))\
+  )\
+)
+endef
+$(call host-cross-select-bitness-of-required-modules)
 r_r :=
 
 define add-required-deps
@@ -628,30 +662,42 @@ $(1): $(2)
 endef
 
 # Sets up dependencies such that whenever a host module is installed,
-# any other host modules listed in $(ALL_MODULES.$(m).REQUIRED) will also be installed
+# any other host modules listed in $(ALL_MODULES.$(m).REQUIRED_FROM_HOST) will also be installed
 define add-all-host-to-host-required-modules-deps
 $(foreach m,$(ALL_MODULES), \
-  $(eval r := $(ALL_MODULES.$(m).REQUIRED)) \
+  $(eval r := $(ALL_MODULES.$(m).REQUIRED_FROM_HOST)) \
   $(if $(r), \
     $(eval r := $(call module-installed-files,$(r))) \
     $(eval h_m := $(filter $(HOST_OUT)/%, $(ALL_MODULES.$(m).INSTALLED))) \
-    $(eval hc_m := $(filter $(HOST_CROSS_OUT)/%, $(ALL_MODULES.$(m).INSTALLED))) \
     $(eval h_r := $(filter $(HOST_OUT)/%, $(r))) \
-    $(eval hc_r := $(filter $(HOST_CROSS_OUT)/%, $(r))) \
     $(eval h_m := $(filter-out $(h_r), $(h_m))) \
-    $(eval hc_m := $(filter-out $(hc_r), $(hc_m))) \
     $(if $(h_m), $(eval $(call add-required-deps, $(h_m),$(h_r)))) \
-    $(if $(hc_m), $(eval $(call add-required-deps, $(hc_m),$(hc_r)))) \
   ) \
 )
 endef
 $(call add-all-host-to-host-required-modules-deps)
 
+# Sets up dependencies such that whenever a host cross module is installed,
+# any other host cross modules listed in $(ALL_MODULES.$(m).REQUIRED_FROM_HOST_CROSS) will also be installed
+define add-all-host-cross-to-host-cross-required-modules-deps
+$(foreach m,$(ALL_MODULES), \
+  $(eval r := $(ALL_MODULES.$(m).REQUIRED_FROM_HOST_CROSS)) \
+  $(if $(r), \
+    $(eval r := $(call module-installed-files,$(r))) \
+    $(eval hc_m := $(filter $(HOST_CROSS_OUT)/%, $(ALL_MODULES.$(m).INSTALLED))) \
+    $(eval hc_r := $(filter $(HOST_CROSS_OUT)/%, $(r))) \
+    $(eval hc_m := $(filter-out $(hc_r), $(hc_m))) \
+    $(if $(hc_m), $(eval $(call add-required-deps, $(hc_m),$(hc_r)))) \
+  ) \
+)
+endef
+$(call add-all-host-cross-to-host-cross-required-modules-deps)
+
 # Sets up dependencies such that whenever a target module is installed,
-# any other target modules listed in $(ALL_MODULES.$(m).REQUIRED) will also be installed
+# any other target modules listed in $(ALL_MODULES.$(m).REQUIRED_FROM_TARGET) will also be installed
 define add-all-target-to-target-required-modules-deps
 $(foreach m,$(ALL_MODULES), \
-  $(eval r := $(ALL_MODULES.$(m).REQUIRED)) \
+  $(eval r := $(ALL_MODULES.$(m).REQUIRED_FROM_TARGET)) \
   $(if $(r), \
     $(eval r := $(call module-installed-files,$(r))) \
     $(eval t_m := $(filter $(TARGET_OUT_ROOT)/%, $(ALL_MODULES.$(m).INSTALLED))) \
@@ -664,10 +710,10 @@ endef
 $(call add-all-target-to-target-required-modules-deps)
 
 # Sets up dependencies such that whenever a host module is installed,
-# any target modules listed in $(ALL_MODULES.$(m).TARGET_REQUIRED) will also be installed
+# any target modules listed in $(ALL_MODULES.$(m).TARGET_REQUIRED_FROM_HOST) will also be installed
 define add-all-host-to-target-required-modules-deps
 $(foreach m,$(ALL_MODULES), \
-  $(eval req_mods := $(ALL_MODULES.$(m).TARGET_REQUIRED))\
+  $(eval req_mods := $(ALL_MODULES.$(m).TARGET_REQUIRED_FROM_HOST))\
   $(if $(req_mods), \
     $(eval req_files := )\
     $(foreach req_mod,$(req_mods), \
@@ -690,10 +736,10 @@ endef
 $(call add-all-host-to-target-required-modules-deps)
 
 # Sets up dependencies such that whenever a target module is installed,
-# any host modules listed in $(ALL_MODULES.$(m).HOST_REQUIRED) will also be installed
+# any host modules listed in $(ALL_MODULES.$(m).HOST_REQUIRED_FROM_TARGET) will also be installed
 define add-all-target-to-host-required-modules-deps
 $(foreach m,$(ALL_MODULES), \
-  $(eval req_mods := $(ALL_MODULES.$(m).HOST_REQUIRED))\
+  $(eval req_mods := $(ALL_MODULES.$(m).HOST_REQUIRED_FROM_TARGET))\
   $(if $(req_mods), \
     $(eval req_files := )\
     $(foreach req_mod,$(req_mods), \
@@ -723,7 +769,7 @@ h_r :=
 hc_r :=
 
 # Establish the dependencies on the shared libraries.
-# It also adds the shared library module names to ALL_MODULES.$(m).REQUIRED,
+# It also adds the shared library module names to ALL_MODULES.$(m).REQUIRED_FROM_(TARGET|HOST|HOST_CROSS),
 # so they can be expanded to product_MODULES later.
 # $(1): TARGET_ or HOST_ or HOST_CROSS_.
 # $(2): non-empty for 2nd arch.
@@ -743,7 +789,7 @@ $(foreach m,$($(if $(2),$($(1)2ND_ARCH_VAR_PREFIX))$(1)DEPENDENCIES_ON_SHARED_LI
     $(eval ALL_MODULES.$(mod).HOST_SHARED_LIBRARIES := $$(ALL_MODULES.$(mod).HOST_SHARED_LIBRARIES) $(deps))\
     $(eval $(call add-required-host-so-deps,$(word 2,$(p)),$(r))),\
     $(eval $(call add-required-deps,$(word 2,$(p)),$(r))))\
-  $(eval ALL_MODULES.$(mod).REQUIRED += $(deps)))
+  $(eval ALL_MODULES.$(mod).REQUIRED_FROM_$(patsubst %_,%,$(1)) += $(deps)))
 endef
 
 # Recursively resolve host shared library dependency for a given module.
@@ -1025,7 +1071,7 @@ endef
 # $(3): The list of overridden modules.
 # Returns empty string (maybe with some whitespaces).
 define expand-required-modules
-$(eval _erm_req := $(foreach m,$(2),$(ALL_MODULES.$(m).REQUIRED))) \
+$(eval _erm_req := $(foreach m,$(2),$(ALL_MODULES.$(m).REQUIRED_FROM_TARGET))) \
 $(eval _erm_new_modules := $(sort $(filter-out $($(1)),$(_erm_req)))) \
 $(eval _erm_new_overrides := $(call module-overrides,$(_erm_new_modules))) \
 $(eval _erm_all_overrides := $(3) $(_erm_new_overrides)) \
@@ -1038,12 +1084,17 @@ endef
 
 # Same as expand-required-modules above, but does not handle module overrides, as
 # we don't intend to support them on the host.
+# $(1): The variable name that holds the initial module name list.
+#       the variable will be modified to hold the expanded results.
+# $(2): The initial module name list.
+# $(3): HOST or HOST_CROSS depending on whether we're expanding host or host cross modules
+# Returns empty string (maybe with some whitespaces).
 define expand-required-host-modules
-$(eval _erm_req := $(foreach m,$(2),$(ALL_MODULES.$(m).REQUIRED))) \
+$(eval _erm_req := $(foreach m,$(2),$(ALL_MODULES.$(m).REQUIRED_FROM_$(3)))) \
 $(eval _erm_new_modules := $(sort $(filter-out $($(1)),$(_erm_req)))) \
 $(eval $(1) += $(_erm_new_modules)) \
 $(if $(_erm_new_modules),\
-  $(call expand-required-host-modules,$(1),$(_erm_new_modules)))
+  $(call expand-required-host-modules,$(1),$(_erm_new_modules),$(3)))
 endef
 
 # Transforms paths relative to PRODUCT_OUT to absolute paths.
@@ -1124,8 +1175,13 @@ define host-installed-files
   $(eval ### For the rest we add both) \
   $(eval _hif_modules += $(call get-host-32-bit-modules, $(_hif_modules_rest))) \
   $(eval _hif_modules += $(_hif_modules_rest)) \
-  $(call expand-required-host-modules,_hif_modules,$(_hif_modules)) \
-  $(filter $(HOST_OUT_ROOT)/%,$(call module-installed-files, $(_hif_modules)))
+  $(eval ### Split host vs host cross modules) \
+  $(eval _hcif_modules := $(filter host_cross_%,$(_hif_modules))) \
+  $(eval _hif_modules := $(filter-out host_cross_%,$(_hif_modules))) \
+  $(call expand-required-host-modules,_hif_modules,$(_hif_modules),HOST) \
+  $(call expand-required-host-modules,_hcif_modules,$(_hcif_modules),HOST_CROSS) \
+  $(filter $(HOST_OUT)/%,$(call module-installed-files, $(_hif_modules))) \
+  $(filter $(HOST_CROSS_OUT)/%,$(call module-installed-files, $(_hcif_modules)))
 endef
 
 # Fails the build if the given list is non-empty, and prints it entries (stripping PRODUCT_OUT).
@@ -1164,7 +1220,7 @@ ifdef FULL_BUILD
     ifneq ($(HOST_OS),darwin)
       _modules := $(PRODUCT_HOST_PACKAGES)
       _nonexistant_modules := $(foreach m,$(_modules),\
-        $(if $(filter FAKE,$(ALL_MODULES.$(m).CLASS))$(filter $(HOST_OUT_ROOT)/%,$(ALL_MODULES.$(m).INSTALLED)),,$(m)))
+        $(if $(ALL_MODULES.$(m).REQUIRED_FROM_HOST)$(filter $(HOST_OUT_ROOT)/%,$(ALL_MODULES.$(m).INSTALLED)),,$(m)))
       $(call maybe-print-list-and-error,$(_nonexistant_modules),\
         $(INTERNAL_PRODUCT) includes non-existant modules in PRODUCT_HOST_PACKAGES)
     endif
diff --git a/core/tasks/tools/package-modules.mk b/core/tasks/tools/package-modules.mk
index 82b4c6a04..d7b3010be 100644
--- a/core/tasks/tools/package-modules.mk
+++ b/core/tasks/tools/package-modules.mk
@@ -21,8 +21,8 @@ my_pickup_files :=
 my_modules_and_deps := $(my_modules)
 $(foreach m,$(my_modules),\
   $(eval _explicitly_required := \
-    $(strip $(ALL_MODULES.$(m).EXPLICITLY_REQUIRED)\
-    $(ALL_MODULES.$(m)$(TARGET_2ND_ARCH_MODULE_SUFFIX).EXPLICITLY_REQUIRED)))\
+    $(strip $(ALL_MODULES.$(m).EXPLICITLY_REQUIRED_FROM_TARGET)\
+    $(ALL_MODULES.$(m)$(TARGET_2ND_ARCH_MODULE_SUFFIX).EXPLICITLY_REQUIRED_FROM_TARGET)))\
   $(eval my_modules_and_deps += $(_explicitly_required))\
 )