diff --git a/core/Makefile b/core/Makefile
index 2595101..0503c35 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -508,6 +508,15 @@
 endef
 
 # $(1): kernel module directory name (top is an out of band value for no directory)
+define build-vendor-kernel-ramdisk-recovery-load
+$(if $(filter top,$(1)),\
+  $(eval _kver :=)$(eval _sep :=),\
+  $(eval _kver := $(1))$(eval _sep :=_))\
+  $(if $(BOARD_VENDOR_KERNEL_RAMDISK_RECOVERY_KERNEL_MODULES_LOAD$(_sep)$(_kver)),\
+    $(call copy-many-files,$(call module-load-list-copy-paths,$(call intermediates-dir-for,PACKAGING,vendor_kernel_ramdisk_recovery_module_list$(_sep)$(_kver)),$(BOARD_VENDOR_KERNEL_RAMDISK_KERNEL_MODULES$(_sep)$(_kver)),$(BOARD_VENDOR_KERNEL_RAMDISK_RECOVERY_KERNEL_MODULES_LOAD$(_sep)$(_kver)),modules.load.recovery,$(TARGET_VENDOR_KERNEL_RAMDISK_OUT))))
+endef
+
+# $(1): kernel module directory name (top is an out of band value for no directory)
 define build-vendor-charger-load
 $(if $(filter top,$(1)),\
   $(eval _kver :=)$(eval _sep :=),\
@@ -578,6 +587,7 @@
   $(eval $(result_var) += $(call build-image-kernel-modules-dir,VENDOR_RAMDISK,$(output_dir),,modules.load,$(VENDOR_RAMDISK_STRIPPED_MODULE_STAGING_DIR),$(kmd))) \
   $(eval ALL_DEFAULT_INSTALLED_MODULES += $(call build-image-kernel-modules-dir,VENDOR_KERNEL_RAMDISK,$(TARGET_VENDOR_KERNEL_RAMDISK_OUT),,modules.load,$(VENDOR_KERNEL_RAMDISK_STRIPPED_MODULE_STAGING_DIR),$(kmd))) \
   $(eval ALL_DEFAULT_INSTALLED_MODULES += $(call build-vendor-ramdisk-recovery-load,$(kmd))) \
+  $(eval ALL_DEFAULT_INSTALLED_MODULES += $(call build-vendor-kernel-ramdisk-recovery-load,$(kmd))) \
   $(eval ALL_DEFAULT_INSTALLED_MODULES += $(call build-image-kernel-modules-dir,VENDOR,$(if $(filter true,$(BOARD_USES_VENDOR_DLKMIMAGE)),$(TARGET_OUT_VENDOR_DLKM),$(TARGET_OUT_VENDOR)),vendor,modules.load,$(VENDOR_STRIPPED_MODULE_STAGING_DIR),$(kmd),$(BOARD_SYSTEM_KERNEL_MODULES),system)) \
   $(eval ALL_DEFAULT_INSTALLED_MODULES += $(call build-vendor-charger-load,$(kmd))) \
   $(eval ALL_DEFAULT_INSTALLED_MODULES += $(call build-image-kernel-modules-dir,ODM,$(if $(filter true,$(BOARD_USES_ODM_DLKMIMAGE)),$(TARGET_OUT_ODM_DLKM),$(TARGET_OUT_ODM)),odm,modules.load,,$(kmd))) \
@@ -918,16 +928,19 @@
 RAMDISK_EXT := .gz
 endif
 
+# This file contains /dev nodes description added to the generic ramdisk
+RAMDISK_NODE_LIST := $(PRODUCT_OUT)/ramdisk_node_list
+
 # We just build this directly to the install location.
 INSTALLED_RAMDISK_TARGET := $(BUILT_RAMDISK_TARGET)
 $(INSTALLED_RAMDISK_TARGET): PRIVATE_DIRS := debug_ramdisk dev metadata mnt proc second_stage_resources sys
-$(INSTALLED_RAMDISK_TARGET): $(MKBOOTFS) $(INTERNAL_RAMDISK_FILES) $(INSTALLED_FILES_FILE_RAMDISK) | $(COMPRESSION_COMMAND_DEPS)
+$(INSTALLED_RAMDISK_TARGET): $(MKBOOTFS) $(RAMDISK_NODE_LIST) $(INTERNAL_RAMDISK_FILES) $(INSTALLED_FILES_FILE_RAMDISK) | $(COMPRESSION_COMMAND_DEPS)
 	$(call pretty,"Target ramdisk: $@")
 	$(hide) mkdir -p $(addprefix $(TARGET_RAMDISK_OUT)/,$(PRIVATE_DIRS))
 ifeq (true,$(BOARD_USES_GENERIC_KERNEL_IMAGE))
 	$(hide) mkdir -p $(addprefix $(TARGET_RAMDISK_OUT)/first_stage_ramdisk/,$(PRIVATE_DIRS))
 endif
-	$(hide) $(MKBOOTFS) -d $(TARGET_OUT) $(TARGET_RAMDISK_OUT) | $(COMPRESSION_COMMAND) > $@
+	$(hide) $(MKBOOTFS) -n $(RAMDISK_NODE_LIST) -d $(TARGET_OUT) $(TARGET_RAMDISK_OUT) | $(COMPRESSION_COMMAND) > $@
 
 $(call declare-1p-container,$(INSTALLED_RAMDISK_TARGET),)
 $(call declare-container-license-deps,$(INSTALLED_RAMDISK_TARGET),$(INTERNAL_RAMDISK_FILE),$(PRODUCT_OUT)/:/)
@@ -5060,6 +5073,7 @@
   img2simg \
   img_from_target_files \
   imgdiff \
+  initrd_bootconfig \
   libconscrypt_openjdk_jni \
   lpmake \
   lpunpack \
diff --git a/core/binary.mk b/core/binary.mk
index 6320726..6f1d814 100644
--- a/core/binary.mk
+++ b/core/binary.mk
@@ -58,6 +58,9 @@
 my_cppflags := $(LOCAL_CPPFLAGS)
 my_cflags_no_override := $(GLOBAL_CLANG_CFLAGS_NO_OVERRIDE)
 my_cppflags_no_override := $(GLOBAL_CLANG_CPPFLAGS_NO_OVERRIDE)
+ifeq ($(my_32_64_bit_suffix), 64)
+  my_cflags_no_override += $(GLOBAL_CLANG_CFLAGS_64_NO_OVERRIDE)
+endif
 ifdef is_third_party
     my_cflags_no_override += $(GLOBAL_CLANG_EXTERNAL_CFLAGS_NO_OVERRIDE)
     my_cppflags_no_override += $(GLOBAL_CLANG_EXTERNAL_CFLAGS_NO_OVERRIDE)
diff --git a/core/config.mk b/core/config.mk
index f5bb7ef..025a3a1 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -431,6 +431,9 @@
 $(hide) $(HOST_NM) -gP $(1) | cut -f1-2 -d" " | (grep -v U$$ >> $(2) || true)
 endef
 
+# Pick a Java compiler.
+include $(BUILD_SYSTEM)/combo/javac.mk
+
 ifeq ($(CALLED_FROM_SETUP),true)
 include $(BUILD_SYSTEM)/ccache.mk
 include $(BUILD_SYSTEM)/goma.mk
@@ -453,9 +456,6 @@
   WITH_TIDY_ONLY :=
 endif
 
-# Pick a Java compiler.
-include $(BUILD_SYSTEM)/combo/javac.mk
-
 # ---------------------------------------------------------------
 # Check that the configuration is current.  We check that
 # BUILD_ENV_SEQUENCE_NUMBER is current against this value.
diff --git a/core/proguard_basic_keeps.flags b/core/proguard_basic_keeps.flags
index 7e7b270..ea200c1 100644
--- a/core/proguard_basic_keeps.flags
+++ b/core/proguard_basic_keeps.flags
@@ -83,13 +83,14 @@
 # 1) runtime-visible annotations will still be kept, and 2) compile-time
 # annotations are stripped by R8 anyway.
 # Note: The ** prefix is used to accommodate jarjar repackaging.
-# TODO(b/242088131): Remove these exemptions after resolving transitive libs
-# dependencies that are provided to R8.
+# TODO(b/266561579): Remove this exemptions after resolving jarjar-ed transitive libs
 -dontwarn **android**.annotation*.**
--dontwarn **com.google.errorprone.annotations.**
--dontwarn javax.annotation.**
--dontwarn org.checkerframework.**
--dontwarn org.jetbrains.annotations.**
+
+# These classes generate warnings of the kind `Library class extends program class`
+# because some apps have deps that statically include the same libraries as the app,
+# and r8 complains that a library is implementing a class provided by the app (the "program").
+-dontwarn com.google.protobuf.**
+-dontwarn kotlin.reflect.jvm.internal.ReflectionFactoryImpl
 
 # Less spammy.
 -dontnote
diff --git a/core/rbe.mk b/core/rbe.mk
index 65abde5..6754b0a 100644
--- a/core/rbe.mk
+++ b/core/rbe.mk
@@ -81,11 +81,11 @@
   endif
 
   ifdef RBE_R8
-    R8_WRAPPER := $(strip $(RBE_WRAPPER) --labels=type=compile,compiler=r8 --exec_strategy=$(r8_exec_strategy) --platform=$(java_r8_d8_platform) --inputs=$(OUT_DIR)/soong/host/linux-x86/framework/r8-compat-proguard.jar,build/make/core/proguard_basic_keeps.flags --toolchain_inputs=$(JAVA))
+    R8_WRAPPER := $(strip $(RBE_WRAPPER) --labels=type=compile,compiler=r8 --exec_strategy=$(r8_exec_strategy) --platform=$(java_r8_d8_platform) --inputs=$(OUT_DIR)/host/linux-x86/framework/r8.jar,build/make/core/proguard_basic_keeps.flags --toolchain_inputs=$(firstword $(JAVA)))
   endif
 
   ifdef RBE_D8
-    D8_WRAPPER := $(strip $(RBE_WRAPPER) --labels=type=compile,compiler=d8 --exec_strategy=$(d8_exec_strategy) --platform=$(java_r8_d8_platform) --inputs=$(OUT_DIR)/soong/host/linux-x86/framework/d8.jar --toolchain_inputs=$(JAVA))
+    D8_WRAPPER := $(strip $(RBE_WRAPPER) --labels=type=compile,compiler=d8 --exec_strategy=$(d8_exec_strategy) --platform=$(java_r8_d8_platform) --inputs=$(OUT_DIR)/host/linux-x86/framework/d8.jar --toolchain_inputs=$(firstword $(JAVA)))
   endif
 
   rbe_dir :=
diff --git a/core/soong_config.mk b/core/soong_config.mk
index e6c4d64..091fa34 100644
--- a/core/soong_config.mk
+++ b/core/soong_config.mk
@@ -266,6 +266,10 @@
 
 $(call add_json_bool, CompressedApex, $(filter true,$(PRODUCT_COMPRESSED_APEX)))
 
+ifndef APEX_BUILD_FOR_PRE_S_DEVICES
+$(call add_json_bool, TrimmedApex, $(filter true,$(PRODUCT_TRIMMED_APEX)))
+endif
+
 $(call add_json_bool, BoardUsesRecoveryAsBoot, $(filter true,$(BOARD_USES_RECOVERY_AS_BOOT)))
 
 $(call add_json_list, BoardKernelBinaries, $(BOARD_KERNEL_BINARIES))
diff --git a/envsetup.sh b/envsetup.sh
index ab86d5f..32e1a32 100644
--- a/envsetup.sh
+++ b/envsetup.sh
@@ -297,7 +297,22 @@
     if [ -n $ANDROID_PYTHONPATH ]; then
         export PYTHONPATH=${PYTHONPATH//$ANDROID_PYTHONPATH/}
     fi
-    export ANDROID_PYTHONPATH=$T/development/python-packages:
+    # //development/python-packages contains both a pseudo-PYTHONPATH which
+    # mimics an already assembled venv, but also contains real Python packages
+    # that are not in that layout until they are installed. We can fake it for
+    # the latter type by adding the package source directories to the PYTHONPATH
+    # directly. For the former group, we only need to add the python-packages
+    # directory itself.
+    #
+    # This could be cleaned up by converting the remaining packages that are in
+    # the first category into a typical python source layout (that is, another
+    # layer of directory nesting) and automatically adding all subdirectories of
+    # python-packages to the PYTHONPATH instead of manually curating this. We
+    # can't convert the packages like adb to the other style because doing so
+    # would prevent exporting type info from those packages.
+    #
+    # http://b/266688086
+    export ANDROID_PYTHONPATH=$T/development/python-packages/adb:$T/development/python-packages:
     if [ -n $VENDOR_PYTHONPATH ]; then
         ANDROID_PYTHONPATH=$ANDROID_PYTHONPATH$VENDOR_PYTHONPATH
     fi
diff --git a/finalize-locally-mainline-sdk.sh b/finalize-locally-mainline-sdk.sh
index 5285a05..c72ef8c 100755
--- a/finalize-locally-mainline-sdk.sh
+++ b/finalize-locally-mainline-sdk.sh
@@ -17,7 +17,7 @@
     TARGET_BUILD_VARIANT=userdebug UNBUNDLED_BUILD_SDKS_FROM_SOURCE=true "$top/vendor/google/build/mainline_modules_sdks.sh"
 
     # Update prebuilts.
-    "$top/packages/modules/common/tools/finalize_sdk.py" -l -b 0 -f ${MAINLINE_EXTENSION} -r '' 0
+    "$top/prebuilts/build-tools/path/linux-x86/python3" "$top/packages/modules/common/tools/finalize_sdk.py" -l -b 0 -f ${MAINLINE_EXTENSION} -r '' 0
 }
 
 finalize_locally_mainline_sdk
diff --git a/finalize-step-2-for-build-target.sh b/finalize-step-2-for-build-target.sh
index d932b14..b74fd03 100755
--- a/finalize-step-2-for-build-target.sh
+++ b/finalize-step-2-for-build-target.sh
@@ -8,8 +8,6 @@
     local top="$(dirname "$0")"/../..
     local m="$top/build/soong/soong_ui.bash --make-mode TARGET_PRODUCT=aosp_arm64 TARGET_BUILD_VARIANT=userdebug"
 
-    revert_to_unfinalized_state
-
     # vndk etc finalization
     source $top/build/make/finalize-aidl-vndk-sdk-resources.sh
 
diff --git a/tools/auto_gen_test_config.py b/tools/auto_gen_test_config.py
index 943f238..ce64160 100755
--- a/tools/auto_gen_test_config.py
+++ b/tools/auto_gen_test_config.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright (C) 2017 The Android Open Source Project
 #
@@ -69,7 +69,7 @@
   module = os.path.splitext(os.path.basename(target_config))[0]
   instrumentation = instrumentation_elements[0]
   manifest = manifest_elements[0]
-  if instrumentation.attributes.has_key(ATTRIBUTE_LABEL):
+  if ATTRIBUTE_LABEL in instrumentation.attributes:
     label = instrumentation.attributes[ATTRIBUTE_LABEL].value
   else:
     label = module
diff --git a/tools/releasetools/non_ab_ota.py b/tools/releasetools/non_ab_ota.py
index 44bac28..7078d67 100644
--- a/tools/releasetools/non_ab_ota.py
+++ b/tools/releasetools/non_ab_ota.py
@@ -48,17 +48,12 @@
     # if the filesystem is ext4.
     partition_source_info = source_info["fstab"]["/" + name]
     check_first_block = partition_source_info.fs_type == "ext4"
-    # Disable using imgdiff for squashfs. 'imgdiff -z' expects input files to be
-    # in zip formats. However with squashfs, a) all files are compressed in LZ4;
-    # b) the blocks listed in block map may not contain all the bytes for a
-    # given file (because they're rounded to be 4K-aligned).
-    partition_target_info = target_info["fstab"]["/" + name]
-    disable_imgdiff = (partition_source_info.fs_type == "squashfs" or
-                       partition_target_info.fs_type == "squashfs")
+    # Disable imgdiff because it relies on zlib to produce stable output
+    # across different versions, which is often not the case.
     return common.BlockDifference(name, partition_tgt, partition_src,
                                   check_first_block,
                                   version=blockimgdiff_version,
-                                  disable_imgdiff=disable_imgdiff)
+                                  disable_imgdiff=True)
 
   if source_zip:
     # See notes in common.GetUserImage()
@@ -409,7 +404,7 @@
   if updating_boot:
     boot_type, boot_device_expr = common.GetTypeAndDeviceExpr("/boot",
                                                               source_info)
-    d = common.Difference(target_boot, source_boot)
+    d = common.Difference(target_boot, source_boot, "bsdiff")
     _, _, d = d.ComputePatch()
     if d is None:
       include_full_boot = True
diff --git a/tools/releasetools/sign_target_files_apks.py b/tools/releasetools/sign_target_files_apks.py
index 0dd0790..4a12e74 100755
--- a/tools/releasetools/sign_target_files_apks.py
+++ b/tools/releasetools/sign_target_files_apks.py
@@ -532,11 +532,13 @@
       # as a symlink in the current code. So it's a no-op here. Keeping the
       # path here for clarity.
       # Some build props might be stored under path
-      # VENDOR_BOOT/RAMDISK_FRAGMENTS/recovery/RAMDISK/default.prop
-      # so overwrite all files that ends with build.prop or default.prop
+      # VENDOR_BOOT/RAMDISK_FRAGMENTS/recovery/RAMDISK/default.prop, and
+      # default.prop can be a symbolic link to prop.default, so overwrite all
+      # files that ends with build.prop, default.prop or prop.default
       "RECOVERY/RAMDISK/default.prop") or \
         filename.endswith("build.prop") or \
-        filename.endswith("/default.prop")
+        filename.endswith("/default.prop") or \
+        filename.endswith("/prop.default")
 
 
 def ProcessTargetFiles(input_tf_zip, output_tf_zip, misc_info,