+# ---------------------------------------------------------------------------
+# Install
+
+# Many distributions have the custom install script, /sbin/installkernel.
+# If DKMS is installed, 'make install' will eventually recuses back
+# to the this Makefile to build and install external modules.
+# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
+
+install: sub_make_done :=
+
+# ---------------------------------------------------------------------------
+# Tools
+
+ifdef CONFIG_STACK_VALIDATION
+prepare: tools/objtool
+endif
+
+ifdef CONFIG_BPF
+ifdef CONFIG_DEBUG_INFO_BTF
+prepare: tools/bpf/resolve_btfids
+endif
+endif
+
+PHONY += resolve_btfids_clean
+
+resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
+
+# tools/bpf/resolve_btfids directory might not exist
+# in output directory, skip its clean in that case
+resolve_btfids_clean:
+ifneq ($(wildcard $(resolve_btfids_O)),)
+ $(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
+endif
+
+# Clear a bunch of variables before executing the submake
+ifeq ($(quiet),silent_)
+tools_silent=s
+endif
+
+tools/: FORCE
+ $(Q)mkdir -p $(objtree)/tools
+ $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
+
+tools/%: FORCE
+ $(Q)mkdir -p $(objtree)/tools
+ $(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
+