[XEN PATCH v9 05/30] build: prepare to always invoke $(MAKE) from xen/, use $(obj)

[Anthony PERARD <anthony.perard@xxxxxxxxxx>]

In a future patch, when building a subdirectory, we will set
"obj=$subdir" rather than change directory.

Before that, we add "$(obj)" and "$(src)" in as many places as
possible where we will need to know which subdirectory is been built.
"$(obj)" is for files been generated during the build, and "$(src)" is
for files present in the source tree.

For now, we set both to "." in Rules.mk and Makefile.clean.

A few places don't tolerate the addition of "./", this is because make
remove the leading "./" in targets and dependencies in rules, so these
will be change later.

Signed-off-by: Anthony PERARD <anthony.perard@xxxxxxxxxx>
Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
Acked-by: Julien Grall <jgrall@xxxxxxxxxx>
---

Notes:
    v8:
    - acked
    - rebased

 xen/Rules.mk                            |  5 ++-
 xen/arch/arm/Makefile                   | 14 ++++----
 xen/arch/x86/Makefile                   | 48 ++++++++++++-------------
 xen/arch/x86/boot/Makefile              | 14 ++++----
 xen/arch/x86/efi/Makefile               |  6 ++--
 xen/common/Makefile                     |  8 ++---
 xen/common/libelf/Makefile              |  4 +--
 xen/common/libfdt/Makefile              |  6 ++--
 xen/include/Makefile                    | 44 +++++++++++------------
 xen/scripts/Makefile.clean              |  5 ++-
 xen/xsm/flask/Makefile                  | 36 +++++++++----------
 xen/xsm/flask/policy/mkaccess_vector.sh |  7 ++--
 12 files changed, 103 insertions(+), 94 deletions(-)

diff --git a/xen/Rules.mk b/xen/Rules.mk
index 77d359bedaf8..60d1d6c4f583 100644
--- a/xen/Rules.mk
+++ b/xen/Rules.mk
@@ -3,6 +3,9 @@
 # Makefile and are consumed by Rules.mk
 #
 
+obj := .
+src := $(obj)
+
 -include $(BASEDIR)/include/config/auto.conf
 
 include $(XEN_ROOT)/Config.mk
@@ -21,7 +24,7 @@ SPECIAL_DATA_SECTIONS := rodata $(foreach a,1 2 4 8 16, \
                          $(foreach r,rel rel.ro,data.$(r).local)
 
 # The filename build.mk has precedence over Makefile
-include $(firstword $(wildcard build.mk) Makefile)
+include $(firstword $(wildcard $(src)/build.mk) $(src)/Makefile)
 
 # Linking
 # ---------------------------------------------------------------------------
diff --git a/xen/arch/arm/Makefile b/xen/arch/arm/Makefile
index 14952275772b..c993ce72a341 100644
--- a/xen/arch/arm/Makefile
+++ b/xen/arch/arm/Makefile
@@ -90,18 +90,18 @@ ifeq ($(CONFIG_ARM_64),y)
        ln -sf $(@F) $@.efi
 endif
 
-$(TARGET)-syms: $(BASEDIR)/prelink.o xen.lds
-       $(LD) $(XEN_LDFLAGS) -T xen.lds -N $< \
+$(TARGET)-syms: $(BASEDIR)/prelink.o $(obj)/xen.lds
+       $(LD) $(XEN_LDFLAGS) -T $(obj)/xen.lds -N $< \
            $(BASEDIR)/common/symbols-dummy.o -o $(@D)/.$(@F).0
        $(NM) -pa --format=sysv $(@D)/.$(@F).0 \
                | $(BASEDIR)/tools/symbols $(all_symbols) --sysv --sort 
>$(@D)/.$(@F).0.S
        $(MAKE) -f $(BASEDIR)/Rules.mk $(@D)/.$(@F).0.o
-       $(LD) $(XEN_LDFLAGS) -T xen.lds -N $< \
+       $(LD) $(XEN_LDFLAGS) -T $(obj)/xen.lds -N $< \
            $(@D)/.$(@F).0.o -o $(@D)/.$(@F).1
        $(NM) -pa --format=sysv $(@D)/.$(@F).1 \
                | $(BASEDIR)/tools/symbols $(all_symbols) --sysv --sort 
>$(@D)/.$(@F).1.S
        $(MAKE) -f $(BASEDIR)/Rules.mk $(@D)/.$(@F).1.o
-       $(LD) $(XEN_LDFLAGS) -T xen.lds -N $< $(build_id_linker) \
+       $(LD) $(XEN_LDFLAGS) -T $(obj)/xen.lds -N $< $(build_id_linker) \
            $(@D)/.$(@F).1.o -o $@
        $(NM) -pa --format=sysv $(@D)/$(@F) \
                | $(BASEDIR)/tools/symbols --all-symbols --xensyms --sysv 
--sort \
@@ -111,13 +111,13 @@ $(TARGET)-syms: $(BASEDIR)/prelink.o xen.lds
 .PHONY: include
 include:
 
-xen.lds: xen.lds.S FORCE
+$(obj)/xen.lds: $(src)/xen.lds.S FORCE
        $(call if_changed,cpp_lds_S)
 
-dtb.o: $(patsubst "%",%,$(CONFIG_DTB_FILE))
+$(obj)/dtb.o: $(patsubst "%",%,$(CONFIG_DTB_FILE))
 
 .PHONY: clean
 clean::
-       rm -f xen.lds
+       rm -f $(obj)/xen.lds
        rm -f $(BASEDIR)/.xen-syms.[0-9]*
        rm -f $(TARGET).efi
diff --git a/xen/arch/x86/Makefile b/xen/arch/x86/Makefile
index a830b5791e8b..db97ae8c07f0 100644
--- a/xen/arch/x86/Makefile
+++ b/xen/arch/x86/Makefile
@@ -81,7 +81,7 @@ extra-y += asm-macros.i
 extra-y += xen.lds
 
 ifneq ($(CONFIG_HVM),y)
-x86_emulate.o: CFLAGS-y += -Wno-unused-label
+$(obj)/x86_emulate.o: CFLAGS-y += -Wno-unused-label
 endif
 
 efi-y := $(shell if [ ! -r $(BASEDIR)/include/xen/compile.h -o \
@@ -112,8 +112,8 @@ syms-warn-dup-$(CONFIG_SUPPRESS_DUPLICATE_SYMBOL_WARNINGS) 
:=
 syms-warn-dup-$(CONFIG_ENFORCE_UNIQUE_SYMBOLS) := --error-dup
 
 $(TARGET): TMP = $(@D)/.$(@F).elf32
-$(TARGET): $(TARGET)-syms $(efi-y) boot/mkelf32
-       ./boot/mkelf32 $(notes_phdrs) $(TARGET)-syms $(TMP) $(XEN_IMG_OFFSET) \
+$(TARGET): $(TARGET)-syms $(efi-y) $(obj)/boot/mkelf32
+       $(obj)/boot/mkelf32 $(notes_phdrs) $(TARGET)-syms $(TMP) 
$(XEN_IMG_OFFSET) \
                       `$(NM) $(TARGET)-syms | sed -ne 's/^\([^ ]*\) . 
__2M_rwdata_end$$/0x\1/p'`
        od -t x4 -N 8192 $(TMP)  | grep 1badb002 > /dev/null || \
                { echo "No Multiboot1 header found" >&2; false; }
@@ -123,27 +123,27 @@ $(TARGET): $(TARGET)-syms $(efi-y) boot/mkelf32
 
 CFLAGS-$(XEN_BUILD_EFI) += -DXEN_BUILD_EFI
 
-$(TARGET)-syms: $(BASEDIR)/prelink.o xen.lds
-       $(LD) $(XEN_LDFLAGS) -T xen.lds -N $< $(build_id_linker) \
+$(TARGET)-syms: $(BASEDIR)/prelink.o $(obj)/xen.lds
+       $(LD) $(XEN_LDFLAGS) -T $(obj)/xen.lds -N $< $(build_id_linker) \
            $(BASEDIR)/common/symbols-dummy.o -o $(@D)/.$(@F).0
        $(NM) -pa --format=sysv $(@D)/.$(@F).0 \
                | $(BASEDIR)/tools/symbols $(all_symbols) --sysv --sort \
                >$(@D)/.$(@F).0.S
        $(MAKE) -f $(BASEDIR)/Rules.mk $(@D)/.$(@F).0.o
-       $(LD) $(XEN_LDFLAGS) -T xen.lds -N $< $(build_id_linker) \
+       $(LD) $(XEN_LDFLAGS) -T $(obj)/xen.lds -N $< $(build_id_linker) \
            $(@D)/.$(@F).0.o -o $(@D)/.$(@F).1
        $(NM) -pa --format=sysv $(@D)/.$(@F).1 \
                | $(BASEDIR)/tools/symbols $(all_symbols) --sysv --sort 
$(syms-warn-dup-y) \
                >$(@D)/.$(@F).1.S
        $(MAKE) -f $(BASEDIR)/Rules.mk $(@D)/.$(@F).1.o
-       $(LD) $(XEN_LDFLAGS) -T xen.lds -N $< $(build_id_linker) \
+       $(LD) $(XEN_LDFLAGS) -T $(obj)/xen.lds -N $< $(build_id_linker) \
            $(@D)/.$(@F).1.o -o $@
        $(NM) -pa --format=sysv $(@D)/$(@F) \
                | $(BASEDIR)/tools/symbols --all-symbols --xensyms --sysv 
--sort \
                >$(@D)/$(@F).map
        rm -f $(@D)/.$(@F).[0-9]* $(@D)/..$(@F).[0-9]*
 
-note.o: $(TARGET)-syms
+$(obj)/note.o: $(TARGET)-syms
        $(OBJCOPY) -O binary --only-section=.note.gnu.build-id $< $@.bin
        $(OBJCOPY) -I binary -O elf64-x86-64 -B i386:x86-64 \
                --rename-section=.data=.note.gnu.build-id -S $@.bin $@
@@ -162,25 +162,25 @@ ifdef SOURCE_DATE_EPOCH
 EFI_LDFLAGS += --no-insert-timestamp
 endif
 
-$(TARGET).efi: VIRT_BASE = 0x$(shell $(NM) efi/relocs-dummy.o | sed -n 's, A 
VIRT_START$$,,p')
+$(TARGET).efi: VIRT_BASE = 0x$(shell $(NM) $(obj)/efi/relocs-dummy.o | sed -n 
's, A VIRT_START$$,,p')
 ifeq ($(MKRELOC),:)
 relocs-dummy :=
 $(TARGET).efi: ALT_BASE :=
 else
-relocs-dummy := efi/relocs-dummy.o
-$(TARGET).efi: ALT_BASE = 0x$(shell $(NM) efi/relocs-dummy.o | sed -n 's, A 
ALT_START$$,,p')
+relocs-dummy := $(obj)/efi/relocs-dummy.o
+$(TARGET).efi: ALT_BASE = 0x$(shell $(NM) $(obj)/efi/relocs-dummy.o | sed -n 
's, A ALT_START$$,,p')
 endif
 
 ifneq ($(build_id_linker),)
 ifeq ($(call ld-ver-build-id,$(LD) $(filter -m%,$(EFI_LDFLAGS))),y)
 CFLAGS-y += -DBUILD_ID_EFI
 EFI_LDFLAGS += $(build_id_linker)
-note_file := efi/buildid.o
+note_file := $(obj)/efi/buildid.o
 # NB: this must be the last input in the linker call, because inputs following
 # the -b option will all be treated as being in the specified format.
 note_file_option := -b pe-x86-64 $(note_file)
 else
-note_file := note.o
+note_file := $(obj)/note.o
 endif
 else
 note_file :=
@@ -189,25 +189,25 @@ note_file_option ?= $(note_file)
 
 ifeq ($(XEN_BUILD_PE),y)
 extra-y += efi.lds
-$(TARGET).efi: $(BASEDIR)/prelink.o $(note_file) efi.lds efi/relocs-dummy.o 
efi/mkreloc
+$(TARGET).efi: $(BASEDIR)/prelink.o $(note_file) $(obj)/efi.lds 
$(obj)/efi/relocs-dummy.o $(obj)/efi/mkreloc
 ifeq ($(CONFIG_DEBUG_INFO),y)
        $(if $(filter --strip-debug,$(EFI_LDFLAGS)),echo,:) "Will strip debug 
info from $(@F)"
 endif
        $(foreach base, $(VIRT_BASE) $(ALT_BASE), \
-                 $(LD) $(call EFI_LDFLAGS,$(base)) -T efi.lds -N $< 
$(relocs-dummy) \
+                 $(LD) $(call EFI_LDFLAGS,$(base)) -T $(obj)/efi.lds -N $< 
$(relocs-dummy) \
                        $(BASEDIR)/common/symbols-dummy.o $(note_file_option) 
-o $(@D)/.$(@F).$(base).0 &&) :
        $(MKRELOC) $(foreach base,$(VIRT_BASE) 
$(ALT_BASE),$(@D)/.$(@F).$(base).0) >$(@D)/.$(@F).0r.S
        $(NM) -pa --format=sysv $(@D)/.$(@F).$(VIRT_BASE).0 \
                | $(BASEDIR)/tools/symbols $(all_symbols) --sysv --sort 
>$(@D)/.$(@F).0s.S
        $(MAKE) -f $(BASEDIR)/Rules.mk $(@D)/.$(@F).0r.o $(@D)/.$(@F).0s.o
        $(foreach base, $(VIRT_BASE) $(ALT_BASE), \
-                 $(LD) $(call EFI_LDFLAGS,$(base)) -T efi.lds -N $< \
+                 $(LD) $(call EFI_LDFLAGS,$(base)) -T $(obj)/efi.lds -N $< \
                        $(@D)/.$(@F).0r.o $(@D)/.$(@F).0s.o $(note_file_option) 
-o $(@D)/.$(@F).$(base).1 &&) :
        $(MKRELOC) $(foreach base,$(VIRT_BASE) 
$(ALT_BASE),$(@D)/.$(@F).$(base).1) >$(@D)/.$(@F).1r.S
        $(NM) -pa --format=sysv $(@D)/.$(@F).$(VIRT_BASE).1 \
                | $(BASEDIR)/tools/symbols $(all_symbols) --sysv --sort 
>$(@D)/.$(@F).1s.S
        $(MAKE) -f $(BASEDIR)/Rules.mk $(@D)/.$(@F).1r.o $(@D)/.$(@F).1s.o
-       $(LD) $(call EFI_LDFLAGS,$(VIRT_BASE)) -T efi.lds -N $< \
+       $(LD) $(call EFI_LDFLAGS,$(VIRT_BASE)) -T $(obj)/efi.lds -N $< \
                        $(@D)/.$(@F).1r.o $(@D)/.$(@F).1s.o $(note_file_option) 
-o $@
        $(NM) -pa --format=sysv $(@D)/$(@F) \
                | $(BASEDIR)/tools/symbols --all-symbols --xensyms --sysv 
--sort >$(@D)/$(@F).map
@@ -219,14 +219,14 @@ $(TARGET).efi: FORCE
 endif
 
 # These should already have been rebuilt when building the prerequisite of 
"prelink.o"
-efi/buildid.o efi/relocs-dummy.o: ;
+$(obj)/efi/buildid.o $(obj)/efi/relocs-dummy.o: ;
 
 .PHONY: include
 include: $(BASEDIR)/arch/x86/include/asm/asm-macros.h
 
-asm-macros.i: CFLAGS-y += -D__ASSEMBLY__ -P
+$(obj)/asm-macros.i: CFLAGS-y += -D__ASSEMBLY__ -P
 
-$(BASEDIR)/arch/x86/include/asm/asm-macros.h: asm-macros.i Makefile
+$(BASEDIR)/arch/x86/include/asm/asm-macros.h: $(obj)/asm-macros.i 
$(src)/Makefile
        echo '#if 0' >$@.new
        echo '.if 0' >>$@.new
        echo '#endif' >>$@.new
@@ -240,14 +240,14 @@ $(BASEDIR)/arch/x86/include/asm/asm-macros.h: 
asm-macros.i Makefile
        echo '#endif' >>$@.new
        $(call move-if-changed,$@.new,$@)
 
-efi.lds: AFLAGS-y += -DEFI
-xen.lds efi.lds: xen.lds.S FORCE
+$(obj)/efi.lds: AFLAGS-y += -DEFI
+$(obj)/xen.lds $(obj)/efi.lds: $(src)/xen.lds.S FORCE
        $(call if_changed,cpp_lds_S)
 
-boot/mkelf32: boot/mkelf32.c
+$(obj)/boot/mkelf32: $(src)/boot/mkelf32.c
        $(HOSTCC) $(HOSTCFLAGS) -o $@ $<
 
-efi/mkreloc: efi/mkreloc.c
+$(obj)/efi/mkreloc: $(src)/efi/mkreloc.c
        $(HOSTCC) $(HOSTCFLAGS) -g -o $@ $<
 
 .PHONY: clean
diff --git a/xen/arch/x86/boot/Makefile b/xen/arch/x86/boot/Makefile
index d2eb277d428f..0aec8a464364 100644
--- a/xen/arch/x86/boot/Makefile
+++ b/xen/arch/x86/boot/Makefile
@@ -1,8 +1,8 @@
 obj-bin-y += head.o
 
-DEFS_H_DEPS = defs.h $(BASEDIR)/include/xen/stdbool.h
+DEFS_H_DEPS = $(src)/defs.h $(BASEDIR)/include/xen/stdbool.h
 
-CMDLINE_DEPS = $(DEFS_H_DEPS) video.h \
+CMDLINE_DEPS = $(DEFS_H_DEPS) $(src)/video.h \
               $(BASEDIR)/include/xen/kconfig.h \
               $(BASEDIR)/include/generated/autoconf.h
 
@@ -14,10 +14,10 @@ RELOC_DEPS = $(DEFS_H_DEPS) \
             $(BASEDIR)/include/xen/const.h \
             $(BASEDIR)/include/public/arch-x86/hvm/start_info.h
 
-head.o: cmdline.S reloc.S
+$(obj)/head.o: $(obj)/cmdline.S $(obj)/reloc.S
 
-cmdline.S: cmdline.c $(CMDLINE_DEPS) build32.lds
-       $(MAKE) -f build32.mk $@ CMDLINE_DEPS="$(CMDLINE_DEPS)"
+$(obj)/cmdline.S: $(src)/cmdline.c $(CMDLINE_DEPS) $(src)/build32.lds
+       $(MAKE) -f build32.mk -C $(obj) $(@F) CMDLINE_DEPS="$(CMDLINE_DEPS)"
 
-reloc.S: reloc.c $(RELOC_DEPS) build32.lds
-       $(MAKE) -f build32.mk $@ RELOC_DEPS="$(RELOC_DEPS)"
+$(obj)/reloc.S: $(src)/reloc.c $(RELOC_DEPS) $(src)/build32.lds
+       $(MAKE) -f build32.mk -C $(obj) $(@F) RELOC_DEPS="$(RELOC_DEPS)"
diff --git a/xen/arch/x86/efi/Makefile b/xen/arch/x86/efi/Makefile
index abae493bf344..e08b4d8e4808 100644
--- a/xen/arch/x86/efi/Makefile
+++ b/xen/arch/x86/efi/Makefile
@@ -3,16 +3,16 @@ CFLAGS-y += -fshort-wchar
 quiet_cmd_objcopy_o_ihex = OBJCOPY $@
 cmd_objcopy_o_ihex = $(OBJCOPY) -I ihex -O binary $< $@
 
-%.o: %.ihex FORCE
+$(obj)/%.o: $(src)/%.ihex FORCE
        $(call if_changed,objcopy_o_ihex)
 
-boot.init.o: buildid.o
+$(obj)/boot.init.o: $(obj)/buildid.o
 
 EFIOBJ-y := boot.init.o pe.init.o ebmalloc.o runtime.o
 EFIOBJ-$(CONFIG_COMPAT) += compat.o
 
 $(call cc-option-add,cflags-stack-boundary,CC,-mpreferred-stack-boundary=4)
-$(EFIOBJ-y): CFLAGS_stack_boundary := $(cflags-stack-boundary)
+$(addprefix $(obj)/,$(EFIOBJ-y)): CFLAGS_stack_boundary := 
$(cflags-stack-boundary)
 
 obj-y := stub.o
 obj-$(XEN_BUILD_EFI) := $(filter-out %.init.o,$(EFIOBJ-y))
diff --git a/xen/common/Makefile b/xen/common/Makefile
index 141d7d40d3dc..ca839118e4d1 100644
--- a/xen/common/Makefile
+++ b/xen/common/Makefile
@@ -75,13 +75,13 @@ obj-$(CONFIG_NEEDS_LIBELF) += libelf/
 obj-$(CONFIG_HAS_DEVICE_TREE) += libfdt/
 
 CONF_FILE := $(if $(patsubst 
/%,,$(KCONFIG_CONFIG)),$(BASEDIR)/)$(KCONFIG_CONFIG)
-config.gz: $(CONF_FILE)
+$(obj)/config.gz: $(CONF_FILE)
        gzip -n -c $< >$@
 
-config_data.o: config.gz
+$(obj)/config_data.o: $(obj)/config.gz
 
-config_data.S: $(BASEDIR)/tools/binfile FORCE
-       $(call if_changed,binfile,config.gz xen_config_data)
+$(obj)/config_data.S: $(BASEDIR)/tools/binfile FORCE
+       $(call if_changed,binfile,$(obj)/config.gz xen_config_data)
 targets += config_data.S
 
 clean::
diff --git a/xen/common/libelf/Makefile b/xen/common/libelf/Makefile
index a92326c982e9..8a4522e4e141 100644
--- a/xen/common/libelf/Makefile
+++ b/xen/common/libelf/Makefile
@@ -7,10 +7,10 @@ OBJCOPYFLAGS := $(foreach s,$(SECTIONS),--rename-section 
.$(s)=.init.$(s))
 
 CFLAGS-y += -Wno-pointer-sign
 
-libelf.o: libelf-temp.o FORCE
+$(obj)/libelf.o: $(obj)/libelf-temp.o FORCE
        $(call if_changed,objcopy)
 
-libelf-temp.o: $(libelf-objs) FORCE
+$(obj)/libelf-temp.o: $(addprefix $(obj)/,$(libelf-objs)) FORCE
        $(call if_changed,ld)
 
 extra-y += libelf-temp.o $(libelf-objs)
diff --git a/xen/common/libfdt/Makefile b/xen/common/libfdt/Makefile
index 6bd207cf8ffa..6708af12e583 100644
--- a/xen/common/libfdt/Makefile
+++ b/xen/common/libfdt/Makefile
@@ -1,4 +1,4 @@
-include Makefile.libfdt
+include $(src)/Makefile.libfdt
 
 SECTIONS := text data $(SPECIAL_DATA_SECTIONS)
 OBJCOPYFLAGS := $(foreach s,$(SECTIONS),--rename-section .$(s)=.init.$(s))
@@ -8,10 +8,10 @@ nocov-y += libfdt.o
 
 CFLAGS-y += -I$(BASEDIR)/include/xen/libfdt/
 
-libfdt.o: libfdt-temp.o FORCE
+$(obj)/libfdt.o: $(obj)/libfdt-temp.o FORCE
        $(call if_changed,objcopy)
 
-libfdt-temp.o: $(LIBFDT_OBJS) FORCE
+$(obj)/libfdt-temp.o: $(addprefix $(obj)/,$(LIBFDT_OBJS)) FORCE
        $(call if_changed,ld)
 
 extra-y += libfdt-temp.o $(LIBFDT_OBJS)
diff --git a/xen/include/Makefile b/xen/include/Makefile
index 95daa8a28975..d2f5a956a11a 100644
--- a/xen/include/Makefile
+++ b/xen/include/Makefile
@@ -39,57 +39,57 @@ cppflags-$(CONFIG_X86)    += -m32
 
 endif
 
-public-$(CONFIG_X86) := $(wildcard public/arch-x86/*.h public/arch-x86/*/*.h)
-public-$(CONFIG_ARM) := $(wildcard public/arch-arm/*.h public/arch-arm/*/*.h)
+public-$(CONFIG_X86) := $(wildcard $(src)/public/arch-x86/*.h 
$(src)/public/arch-x86/*/*.h)
+public-$(CONFIG_ARM) := $(wildcard $(src)/public/arch-arm/*.h 
$(src)/public/arch-arm/*/*.h)
 
 .PHONY: all
-all: $(headers-y)
+all: $(addprefix $(obj)/,$(headers-y))
 
-compat/%.h: compat/%.i Makefile $(BASEDIR)/tools/compat-build-header.py
-       $(PYTHON) $(BASEDIR)/tools/compat-build-header.py <$< $@ >>$@.new; \
+$(obj)/compat/%.h: $(obj)/compat/%.i $(src)/Makefile 
$(BASEDIR)/tools/compat-build-header.py
+       $(PYTHON) $(BASEDIR)/tools/compat-build-header.py <$< $(patsubst 
$(obj)/%,%,$@) >>$@.new; \
        mv -f $@.new $@
 
-compat/%.i: compat/%.c Makefile
+$(obj)/compat/%.i: $(obj)/compat/%.c $(src)/Makefile
        $(CPP) $(filter-out -Wa$(comma)% -include 
%/include/xen/config.h,$(XEN_CFLAGS)) $(cppflags-y) -o $@ $<
 
-compat/%.c: public/%.h xlat.lst Makefile 
$(BASEDIR)/tools/compat-build-source.py
+$(obj)/compat/%.c: $(src)/public/%.h $(src)/xlat.lst $(src)/Makefile 
$(BASEDIR)/tools/compat-build-source.py
        mkdir -p $(@D)
-       $(PYTHON) $(BASEDIR)/tools/compat-build-source.py xlat.lst <$< >$@.new
+       $(PYTHON) $(BASEDIR)/tools/compat-build-source.py $(src)/xlat.lst <$< 
>$@.new
        mv -f $@.new $@
 
-compat/.xlat/%.h: compat/%.h compat/.xlat/%.lst $(BASEDIR)/tools/get-fields.sh 
Makefile
+$(obj)/compat/.xlat/%.h: $(obj)/compat/%.h $(obj)/compat/.xlat/%.lst 
$(BASEDIR)/tools/get-fields.sh $(src)/Makefile
        export PYTHON=$(PYTHON); \
        while read what name; do \
                $(SHELL) $(BASEDIR)/tools/get-fields.sh "$$what" compat_$$name 
$< || exit $$?; \
        done <$(patsubst compat/%,compat/.xlat/%,$(basename $<)).lst >$@.new
        mv -f $@.new $@
 
-.PRECIOUS: compat/.xlat/%.lst
-compat/.xlat/%.lst: xlat.lst Makefile
+.PRECIOUS: $(obj)/compat/.xlat/%.lst
+$(obj)/compat/.xlat/%.lst: $(src)/xlat.lst $(src)/Makefile
        mkdir -p $(@D)
        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' xlat.lst | uniq)
+xlat-y := $(shell sed -ne 's,@arch@,$(compat-arch-y),g' -re 
's,^[?!][[:blank:]]+[^[:blank:]]+[[:blank:]]+,,p' $(src)/xlat.lst | uniq)
 xlat-y := $(filter $(patsubst compat/%,%,$(headers-y)),$(xlat-y))
 
-compat/xlat.h: $(addprefix compat/.xlat/,$(xlat-y)) config/auto.conf Makefile
+$(obj)/compat/xlat.h: $(addprefix $(obj)/compat/.xlat/,$(xlat-y)) 
$(obj)/config/auto.conf $(src)/Makefile
        cat $(filter %.h,$^) >$@.new
        mv -f $@.new $@
 
 ifeq ($(XEN_TARGET_ARCH),$(XEN_COMPILE_ARCH))
 
-all: headers.chk headers99.chk headers++.chk
+all: $(obj)/headers.chk $(obj)/headers99.chk $(obj)/headers++.chk
 
-PUBLIC_HEADERS := $(filter-out public/arch-% public/dom0_ops.h, $(wildcard 
public/*.h public/*/*.h) $(public-y))
+PUBLIC_HEADERS := $(filter-out $(src)/public/arch-% $(src)/public/dom0_ops.h, 
$(wildcard $(src)/public/*.h $(src)/public/*/*.h) $(public-y))
 
-PUBLIC_C99_HEADERS := public/io/9pfs.h public/io/pvcalls.h
-PUBLIC_ANSI_HEADERS := $(filter-out public/%ctl.h public/xsm/% 
public/%hvm/save.h $(PUBLIC_C99_HEADERS), $(PUBLIC_HEADERS))
+PUBLIC_C99_HEADERS := $(src)/public/io/9pfs.h $(src)/public/io/pvcalls.h
+PUBLIC_ANSI_HEADERS := $(filter-out $(src)/public/%ctl.h $(src)/public/xsm/% 
$(src)/public/%hvm/save.h $(PUBLIC_C99_HEADERS), $(PUBLIC_HEADERS))
 
 public/io/9pfs.h-prereq := string
 public/io/pvcalls.h-prereq := string
 
-headers.chk: $(PUBLIC_ANSI_HEADERS) Makefile
+$(obj)/headers.chk: $(PUBLIC_ANSI_HEADERS) $(src)/Makefile
        for i in $(filter %.h,$^); do \
            $(CC) -x c -ansi -Wall -Werror -include stdint.h \
                  -S -o /dev/null $$i || exit 1; \
@@ -97,7 +97,7 @@ headers.chk: $(PUBLIC_ANSI_HEADERS) Makefile
        done >$@.new
        mv $@.new $@
 
-headers99.chk: $(PUBLIC_C99_HEADERS) Makefile
+$(obj)/headers99.chk: $(PUBLIC_C99_HEADERS) $(src)/Makefile
        rm -f $@.new
        $(foreach i, $(filter %.h,$^),                                        \
            echo "#include "\"$(i)\"                                          \
@@ -107,7 +107,7 @@ headers99.chk: $(PUBLIC_C99_HEADERS) Makefile
            || exit $$?; echo $(i) >> $@.new;)
        mv $@.new $@
 
-headers++.chk: $(PUBLIC_HEADERS) Makefile
+$(obj)/headers++.chk: $(PUBLIC_HEADERS) $(src)/Makefile
        rm -f $@.new
        if ! $(CXX) -v >/dev/null 2>&1; then                                  \
            touch $@.new;                                                     \
@@ -116,7 +116,7 @@ headers++.chk: $(PUBLIC_HEADERS) Makefile
        $(foreach i, $(filter %.h,$^),                                        \
            echo "#include "\"$(i)\"                                          \
            | $(CXX) -x c++ -std=gnu++98 -Wall -Werror -D__XEN_TOOLS__        \
-             -include stdint.h -include public/xen.h                         \
+             -include stdint.h -include $(src)/public/xen.h                  \
              $(foreach j, $($(i)-prereq), -include c$(j)) -S -o /dev/null -  \
            || exit $$?; echo $(i) >> $@.new;)
        mv $@.new $@
@@ -126,7 +126,7 @@ endif
 ifeq ($(XEN_TARGET_ARCH),x86_64)
 .PHONY: lib-x86-all
 lib-x86-all:
-       $(MAKE) -C xen/lib/x86 all
+       $(MAKE) -C $(obj)/xen/lib/x86 all
 
 all: lib-x86-all
 endif
diff --git a/xen/scripts/Makefile.clean b/xen/scripts/Makefile.clean
index 8582ec35e4da..c3b0681611da 100644
--- a/xen/scripts/Makefile.clean
+++ b/xen/scripts/Makefile.clean
@@ -3,11 +3,14 @@
 # Cleaning up
 # ==========================================================================
 
+obj := .
+src := $(obj)
+
 clean::
 
 include $(BASEDIR)/scripts/Kbuild.include
 
-include Makefile
+include $(src)/Makefile
 
 # Figure out what we need to clean from the various variables
 # ==========================================================================
diff --git a/xen/xsm/flask/Makefile b/xen/xsm/flask/Makefile
index 11c530dcf458..51fd37f6c4d5 100644
--- a/xen/xsm/flask/Makefile
+++ b/xen/xsm/flask/Makefile
@@ -4,46 +4,46 @@ obj-y += flask_op.o
 
 obj-y += ss/
 
-CFLAGS-y += -I./include
+CFLAGS-y += -I$(obj)/include
 
 AWK = awk
 
-FLASK_H_DEPEND = policy/security_classes policy/initial_sids
-AV_H_DEPEND = policy/access_vectors
+FLASK_H_DEPEND := $(addprefix $(src)/policy/,security_classes initial_sids)
+AV_H_DEPEND = $(src)/policy/access_vectors
 
-FLASK_H_FILES = include/flask.h include/class_to_string.h 
include/initial_sid_to_string.h
-AV_H_FILES = include/av_perm_to_string.h include/av_permissions.h
-ALL_H_FILES = $(FLASK_H_FILES) $(AV_H_FILES)
+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
+ALL_H_FILES := $(addprefix include/,$(FLASK_H_FILES) $(AV_H_FILES))
 
-$(obj-y) ss/built_in.o: $(ALL_H_FILES)
+$(addprefix $(obj)/,$(obj-y)) $(obj)/ss/built_in.o: $(addprefix 
$(obj)/,$(ALL_H_FILES))
 extra-y += $(ALL_H_FILES)
 
-mkflask := policy/mkflask.sh
+mkflask := $(src)/policy/mkflask.sh
 quiet_cmd_mkflask = MKFLASK $@
-cmd_mkflask = $(SHELL) $(mkflask) $(AWK) include $(FLASK_H_DEPEND)
+cmd_mkflask = $(SHELL) $(mkflask) $(AWK) $(obj)/include $(FLASK_H_DEPEND)
 
-$(subst include/,%/,$(FLASK_H_FILES)): $(FLASK_H_DEPEND) $(mkflask) FORCE
+$(addprefix $(obj)/%/,$(FLASK_H_FILES)): $(FLASK_H_DEPEND) $(mkflask) FORCE
        $(call if_changed,mkflask)
 
-mkaccess := policy/mkaccess_vector.sh
+mkaccess := $(src)/policy/mkaccess_vector.sh
 quiet_cmd_mkaccess = MKACCESS VECTOR $@
-cmd_mkaccess = $(SHELL) $(mkaccess) $(AWK) $(AV_H_DEPEND)
+cmd_mkaccess = $(SHELL) $(mkaccess) $(AWK) $(obj)/include $(AV_H_DEPEND)
 
-$(subst include/,%/,$(AV_H_FILES)): $(AV_H_DEPEND) $(mkaccess) FORCE
+$(addprefix $(obj)/%/,$(AV_H_FILES)): $(AV_H_DEPEND) $(mkaccess) FORCE
        $(call if_changed,mkaccess)
 
 obj-bin-$(CONFIG_XSM_FLASK_POLICY) += flask-policy.o
-flask-policy.o: policy.bin
+$(obj)/flask-policy.o: $(obj)/policy.bin
 
-flask-policy.S: BINFILE_FLAGS := -i
-flask-policy.S: $(BASEDIR)/tools/binfile FORCE
-       $(call if_changed,binfile,policy.bin xsm_flask_init_policy)
+$(obj)/flask-policy.S: BINFILE_FLAGS := -i
+$(obj)/flask-policy.S: $(BASEDIR)/tools/binfile FORCE
+       $(call if_changed,binfile,$(obj)/policy.bin xsm_flask_init_policy)
 targets += flask-policy.S
 
 FLASK_BUILD_DIR := $(CURDIR)
 POLICY_SRC := $(FLASK_BUILD_DIR)/xenpolicy-$(XEN_FULLVERSION)
 
-policy.bin: FORCE
+$(obj)/policy.bin: FORCE
        $(MAKE) -f $(XEN_ROOT)/tools/flask/policy/Makefile.common \
                -C $(XEN_ROOT)/tools/flask/policy \
                FLASK_BUILD_DIR=$(FLASK_BUILD_DIR) POLICY_FILENAME=$(POLICY_SRC)
diff --git a/xen/xsm/flask/policy/mkaccess_vector.sh 
b/xen/xsm/flask/policy/mkaccess_vector.sh
index 942ede4713f1..ad9772193bff 100755
--- a/xen/xsm/flask/policy/mkaccess_vector.sh
+++ b/xen/xsm/flask/policy/mkaccess_vector.sh
@@ -8,9 +8,12 @@ set -e
 awk=$1
 shift
 
+output_dir=$1
+shift
+
 # output files
-av_permissions="include/av_permissions.h"
-av_perm_to_string="include/av_perm_to_string.h"
+av_permissions="$output_dir/av_permissions.h"
+av_perm_to_string="$output_dir/av_perm_to_string.h"
 
 cat $* | $awk "
 BEGIN  {
-- 
Anthony PERARD