diff --git a/xen/Kconfig b/xen/Kconfig
index bcbd2758e5d3..ac9a638d372e 100644
--- a/xen/Kconfig
+++ b/xen/Kconfig
@@ -14,14 +14,14 @@ config CC_IS_GCC
 
 config GCC_VERSION
 	int
-	default $(shell,$(BASEDIR)/scripts/gcc-version.sh $(CC))
+	default $(shell,$(srctree)/scripts/gcc-version.sh $(CC))
 
 config CC_IS_CLANG
 	def_bool $(success,$(CC) --version | head -n 1 | grep -q clang)
 
 config CLANG_VERSION
 	int
-	default $(shell,$(BASEDIR)/scripts/clang-version.sh $(CC))
+	default $(shell,$(srctree)/scripts/clang-version.sh $(CC))
 
 # -fvisibility=hidden reduces -fpic cost, if it's available
 config CC_HAS_VISIBILITY_ATTRIBUTE
diff --git a/xen/Makefile b/xen/Makefile
index 443784dfce80..c39c1699966f 100644
--- a/xen/Makefile
+++ b/xen/Makefile
@@ -19,8 +19,7 @@ export PYTHON		?= $(PYTHON_INTERPRETER)
 
 export CHECKPOLICY	?= checkpolicy
 
-export BASEDIR := $(CURDIR)
-export XEN_ROOT := $(BASEDIR)/..
+export XEN_ROOT := $(CURDIR)/..
 
 abs_objtree := $(CURDIR)
 abs_srctree := $(CURDIR)
@@ -189,7 +188,7 @@ ifeq ($(TARGET_ARCH),x86)
 t1 = $(call as-insn,$(CC),".L0: .L1: .skip (.L1 - .L0)",,-no-integrated-as)
 
 # Check whether clang asm()-s support .include.
-t2 = $(call as-insn,$(CC) -I$(BASEDIR)/arch/x86/include,".include \"asm/asm-defns.h\"",,-no-integrated-as)
+t2 = $(call as-insn,$(CC) -I$(srctree)/arch/x86/include,".include \"asm/asm-defns.h\"",,-no-integrated-as)
 
 # Check whether clang keeps .macro-s between asm()-s:
 # https://bugs.llvm.org/show_bug.cgi?id=36110
@@ -329,7 +328,7 @@ ALL_OBJS-$(CONFIG_CRYPTO) += crypto/built_in.o
 
 ALL_LIBS-y                := lib/lib.a
 
-include $(BASEDIR)/arch/$(TARGET_ARCH)/arch.mk
+include $(srctree)/arch/$(TARGET_ARCH)/arch.mk
 
 # define new variables to avoid the ones defined in Config.mk
 export XEN_CFLAGS := $(CFLAGS)
diff --git a/xen/Rules.mk b/xen/Rules.mk
index 7712bfa063e0..57a029455586 100644
--- a/xen/Rules.mk
+++ b/xen/Rules.mk
@@ -9,13 +9,16 @@ endif
 
 src := $(obj)
 
+# shortcuts
+srcdir := $(srctree)/$(src)
+
 PHONY := __build
 __build:
 
 -include $(objtree)/include/config/auto.conf
 
 include $(XEN_ROOT)/Config.mk
-include $(BASEDIR)/scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
 
 # Initialise some variables
 obj-y :=
@@ -58,7 +61,7 @@ cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $< $@
 # binfile
 # use e.g. $(call if_changed,binfile,binary-file varname)
 quiet_cmd_binfile = BINFILE $@
-cmd_binfile = $(SHELL) $(BASEDIR)/tools/binfile $(BINFILE_FLAGS) $@ $(2)
+cmd_binfile = $(SHELL) $(srctree)/tools/binfile $(BINFILE_FLAGS) $@ $(2)
 
 # Figure out what we need to build from the various variables
 # ===========================================================================
@@ -177,7 +180,7 @@ cpp_flags = $(filter-out -Wa$(comma)% -flto,$(1))
 c_flags = -MMD -MP -MF $(depfile) $(XEN_CFLAGS)
 a_flags = -MMD -MP -MF $(depfile) $(XEN_AFLAGS)
 
-include $(BASEDIR)/arch/$(TARGET_ARCH)/Rules.mk
+include $(srctree)/arch/$(TARGET_ARCH)/Rules.mk
 
 c_flags += $(_c_flags)
 a_flags += $(_c_flags)
diff --git a/xen/arch/x86/arch.mk b/xen/arch/x86/arch.mk
index 8bc0e01ceb2b..2fcb6271faf7 100644
--- a/xen/arch/x86/arch.mk
+++ b/xen/arch/x86/arch.mk
@@ -63,7 +63,7 @@ ifneq ($(CONFIG_PV_SHIM_EXCLUSIVE),y)
 efi-check := arch/x86/efi/check
 
 # Check if the compiler supports the MS ABI.
-XEN_BUILD_EFI := $(call if-success,$(CC) $(CFLAGS) -c $(efi-check).c -o $(efi-check).o,y)
+XEN_BUILD_EFI := $(call if-success,$(CC) $(CFLAGS) -c $(srctree)/$(efi-check).c -o $(efi-check).o,y)
 
 # Check if the linker supports PE.
 EFI_LDFLAGS := $(patsubst -m%,-mi386pep,$(LDFLAGS)) --subsystem=10
diff --git a/xen/build.mk b/xen/build.mk
index e718743ef772..758590c68eab 100644
--- a/xen/build.mk
+++ b/xen/build.mk
@@ -27,9 +27,9 @@ define cmd_compile.h
 	    -e 's/@@version@@/$(XEN_VERSION)/g' \
 	    -e 's/@@subversion@@/$(XEN_SUBVERSION)/g' \
 	    -e 's/@@extraversion@@/$(XEN_EXTRAVERSION)/g' \
-	    -e 's!@@changeset@@!$(shell tools/scmversion $(XEN_ROOT) || echo "unavailable")!g' \
+	    -e 's!@@changeset@@!$(shell $(srctree)/tools/scmversion $(XEN_ROOT) || echo "unavailable")!g' \
 	    < $< > $(dot-target).tmp; \
-	sed -rf tools/process-banner.sed < .banner >> $(dot-target).tmp; \
+	sed -rf $(srctree)/tools/process-banner.sed < .banner >> $(dot-target).tmp; \
 	mv -f $(dot-target).tmp $@; \
     fi
 endef
diff --git a/xen/common/Makefile b/xen/common/Makefile
index 30641a737231..b1e076c30b81 100644
--- a/xen/common/Makefile
+++ b/xen/common/Makefile
@@ -80,7 +80,7 @@ $(obj)/config.gz: $(CONF_FILE)
 
 $(obj)/config_data.o: $(obj)/config.gz
 
-$(obj)/config_data.S: $(BASEDIR)/tools/binfile FORCE
+$(obj)/config_data.S: $(srctree)/tools/binfile FORCE
 	$(call if_changed,binfile,$(obj)/config.gz xen_config_data)
 targets += config_data.S
 
diff --git a/xen/common/libfdt/Makefile b/xen/common/libfdt/Makefile
index 6708af12e583..75aaefa2e37f 100644
--- a/xen/common/libfdt/Makefile
+++ b/xen/common/libfdt/Makefile
@@ -6,7 +6,7 @@ OBJCOPYFLAGS := $(foreach s,$(SECTIONS),--rename-section .$(s)=.init.$(s))
 obj-y += libfdt.o
 nocov-y += libfdt.o
 
-CFLAGS-y += -I$(BASEDIR)/include/xen/libfdt/
+CFLAGS-y += -I$(srctree)/include/xen/libfdt/
 
 $(obj)/libfdt.o: $(obj)/libfdt-temp.o FORCE
 	$(call if_changed,objcopy)
diff --git a/xen/include/Makefile b/xen/include/Makefile
index a3c2511f5f60..5a2b4c9f65fa 100644
--- a/xen/include/Makefile
+++ b/xen/include/Makefile
@@ -45,22 +45,22 @@ public-$(CONFIG_ARM) := $(wildcard $(src)/public/arch-arm/*.h $(src)/public/arch
 .PHONY: all
 all: $(addprefix $(obj)/,$(headers-y))
 
-$(obj)/compat/%.h: $(obj)/compat/%.i $(src)/Makefile $(BASEDIR)/tools/compat-build-header.py
-	$(PYTHON) $(BASEDIR)/tools/compat-build-header.py <$< $(patsubst $(obj)/%,%,$@) >>$@.new; \
+$(obj)/compat/%.h: $(obj)/compat/%.i $(src)/Makefile $(srctree)/tools/compat-build-header.py
+	$(PYTHON) $(srctree)/tools/compat-build-header.py <$< $(patsubst $(obj)/%,%,$@) >>$@.new; \
 	mv -f $@.new $@
 
 $(obj)/compat/%.i: $(obj)/compat/%.c $(src)/Makefile
 	$(CPP) $(filter-out -Wa$(comma)% -include %/include/xen/config.h,$(XEN_CFLAGS)) $(cppflags-y) -o $@ $<
 
-$(obj)/compat/%.c: $(src)/public/%.h $(src)/xlat.lst $(src)/Makefile $(BASEDIR)/tools/compat-build-source.py
+$(obj)/compat/%.c: $(src)/public/%.h $(src)/xlat.lst $(src)/Makefile $(srctree)/tools/compat-build-source.py
 	mkdir -p $(@D)
-	$(PYTHON) $(BASEDIR)/tools/compat-build-source.py $(src)/xlat.lst <$< >$@.new
+	$(PYTHON) $(srctree)/tools/compat-build-source.py $(srcdir)/xlat.lst <$< >$@.new
 	mv -f $@.new $@
 
-$(obj)/compat/.xlat/%.h: $(obj)/compat/%.h $(obj)/compat/.xlat/%.lst $(BASEDIR)/tools/get-fields.sh $(src)/Makefile
+$(obj)/compat/.xlat/%.h: $(obj)/compat/%.h $(obj)/compat/.xlat/%.lst $(srctree)/tools/get-fields.sh $(src)/Makefile
 	export PYTHON=$(PYTHON); \
 	while read what name; do \
-		$(SHELL) $(BASEDIR)/tools/get-fields.sh "$$what" compat_$$name $< || exit $$?; \
+		$(SHELL) $(srctree)/tools/get-fields.sh "$$what" compat_$$name $< || exit $$?; \
 	done <$(patsubst $(obj)/compat/%,$(obj)/compat/.xlat/%,$(basename $<)).lst >$@.new
 	mv -f $@.new $@
 
@@ -70,7 +70,7 @@ $(obj)/compat/.xlat/%.lst: $(src)/xlat.lst $(src)/Makefile
 	grep -v '^[[:blank:]]*#' $< | sed -ne 's,@arch@,$(compat-arch-y),g' -re 's,[[:blank:]]+$*\.h[[:blank:]]*$$,,p' >$@.new
 	$(call move-if-changed,$@.new,$@)
 
-xlat-y := $(shell sed -ne 's,@arch@,$(compat-arch-y),g' -re 's,^[?!][[:blank:]]+[^[:blank:]]+[[:blank:]]+,,p' $(src)/xlat.lst | uniq)
+xlat-y := $(shell sed -ne 's,@arch@,$(compat-arch-y),g' -re 's,^[?!][[:blank:]]+[^[:blank:]]+[[:blank:]]+,,p' $(srcdir)/xlat.lst | uniq)
 xlat-y := $(filter $(patsubst compat/%,%,$(headers-y)),$(xlat-y))
 
 $(obj)/compat/xlat.h: $(addprefix $(obj)/compat/.xlat/,$(xlat-y)) $(obj)/config/auto.conf $(src)/Makefile
diff --git a/xen/scripts/Kconfig.include b/xen/scripts/Kconfig.include
index e1f13e17207e..389a690a127a 100644
--- a/xen/scripts/Kconfig.include
+++ b/xen/scripts/Kconfig.include
@@ -40,4 +40,4 @@ $(error-if,$(failure,command -v $(CC)),compiler '$(CC)' not found)
 $(error-if,$(failure,command -v $(LD)),linker '$(LD)' not found)
 
 # gcc version including patch level
-gcc-version := $(shell,$(BASEDIR)/scripts/gcc-version.sh $(CC))
+gcc-version := $(shell,$(srctree)/scripts/gcc-version.sh $(CC))
diff --git a/xen/scripts/Makefile.clean b/xen/scripts/Makefile.clean
index 4eed31974509..f97ecd3b8eee 100644
--- a/xen/scripts/Makefile.clean
+++ b/xen/scripts/Makefile.clean
@@ -5,9 +5,12 @@
 
 src := $(obj)
 
+# shortcuts
+srcdir := $(srctree)/$(src)
+
 clean::
 
-include $(BASEDIR)/scripts/Kbuild.include
+include $(srctree)/scripts/Kbuild.include
 
 include $(src)/Makefile
 
diff --git a/xen/xsm/flask/Makefile b/xen/xsm/flask/Makefile
index 4ac6fb8778ae..a99038cb5722 100644
--- a/xen/xsm/flask/Makefile
+++ b/xen/xsm/flask/Makefile
@@ -8,8 +8,8 @@ CFLAGS-y += -I$(obj)/include
 
 AWK = awk
 
-FLASK_H_DEPEND := $(addprefix $(src)/policy/,security_classes initial_sids)
-AV_H_DEPEND = $(src)/policy/access_vectors
+FLASK_H_DEPEND := $(addprefix $(srcdir)/policy/,security_classes initial_sids)
+AV_H_DEPEND := $(srcdir)/policy/access_vectors
 
 FLASK_H_FILES := flask.h class_to_string.h initial_sid_to_string.h
 AV_H_FILES := av_perm_to_string.h av_permissions.h
@@ -18,14 +18,14 @@ ALL_H_FILES := $(addprefix include/,$(FLASK_H_FILES) $(AV_H_FILES))
 $(addprefix $(obj)/,$(obj-y)) $(obj)/ss/built_in.o: $(addprefix $(obj)/,$(ALL_H_FILES))
 extra-y += $(ALL_H_FILES)
 
-mkflask := $(src)/policy/mkflask.sh
+mkflask := $(srcdir)/policy/mkflask.sh
 quiet_cmd_mkflask = MKFLASK $@
 cmd_mkflask = $(SHELL) $(mkflask) $(AWK) $(obj)/include $(FLASK_H_DEPEND)
 
 $(addprefix $(obj)/%/,$(FLASK_H_FILES)): $(FLASK_H_DEPEND) $(mkflask) FORCE
 	$(call if_changed,mkflask)
 
-mkaccess := $(src)/policy/mkaccess_vector.sh
+mkaccess := $(srcdir)/policy/mkaccess_vector.sh
 quiet_cmd_mkaccess = MKACCESS VECTOR $@
 cmd_mkaccess = $(SHELL) $(mkaccess) $(AWK) $(obj)/include $(AV_H_DEPEND)
 
@@ -36,7 +36,7 @@ obj-bin-$(CONFIG_XSM_FLASK_POLICY) += flask-policy.o
 $(obj)/flask-policy.o: $(obj)/policy.bin
 
 $(obj)/flask-policy.S: BINFILE_FLAGS := -i
-$(obj)/flask-policy.S: $(BASEDIR)/tools/binfile FORCE
+$(obj)/flask-policy.S: $(srctree)/tools/binfile FORCE
 	$(call if_changed,binfile,$(obj)/policy.bin xsm_flask_init_policy)
 targets += flask-policy.S
 
