1# SPDX-License-Identifier: GPL-2.0
2# Objects to go into the VDSO.
3OBJECT_FILES_NON_STANDARD		:= y
4
5KASAN_SANITIZE := n
6
7# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
8# the inclusion of generic Makefile.
9ARCH_REL_TYPE_ABS := R_LARCH_32|R_LARCH_64|R_LARCH_MARK_LA|R_LARCH_JUMP_SLOT
10include $(srctree)/lib/vdso/Makefile
11
12obj-vdso-y := elf.o vgetcpu.o vgettimeofday.o sigreturn.o
13
14# Common compiler flags between ABIs.
15ccflags-vdso := \
16	$(filter -I%,$(KBUILD_CFLAGS)) \
17	$(filter -E%,$(KBUILD_CFLAGS)) \
18	$(filter -march=%,$(KBUILD_CFLAGS)) \
19	$(filter -m%-float,$(KBUILD_CFLAGS)) \
20	-D__VDSO__
21
22ifeq ($(cc-name),clang)
23ccflags-vdso += $(filter --target=%,$(KBUILD_CFLAGS))
24endif
25
26cflags-vdso := $(ccflags-vdso) \
27	$(filter -W%,$(filter-out -Wa$(comma)%,$(KBUILD_CFLAGS))) \
28	-O2 -g -fno-strict-aliasing -fno-common -fno-builtin \
29	-fno-stack-protector -fno-jump-tables -DDISABLE_BRANCH_PROFILING \
30	$(call cc-option, -fno-asynchronous-unwind-tables) \
31	$(call cc-option, -fno-stack-protector)
32aflags-vdso := $(ccflags-vdso) \
33	-D__ASSEMBLY__ -Wa,-gdwarf-2
34
35ifneq ($(c-gettimeofday-y),)
36  CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y)
37endif
38
39# VDSO linker flags.
40ldflags-y := -Bsymbolic --no-undefined -soname=linux-vdso.so.1 \
41	$(filter -E%,$(KBUILD_CFLAGS)) -nostdlib -shared \
42	--hash-style=sysv --build-id -T
43
44GCOV_PROFILE := n
45
46#
47# Shared build commands.
48#
49
50quiet_cmd_vdsold_and_vdso_check = LD      $@
51      cmd_vdsold_and_vdso_check = $(cmd_ld); $(cmd_vdso_check)
52
53quiet_cmd_vdsoas_o_S = AS       $@
54      cmd_vdsoas_o_S = $(CC) $(a_flags) -c -o $@ $<
55
56# Generate VDSO offsets using helper script
57gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh
58quiet_cmd_vdsosym = VDSOSYM $@
59      cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@
60
61include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
62	$(call if_changed,vdsosym)
63
64#
65# Build native VDSO.
66#
67
68native-abi := $(filter -mabi=%,$(KBUILD_CFLAGS))
69
70targets += $(obj-vdso-y)
71targets += vdso.lds vdso.so.dbg vdso.so
72
73obj-vdso := $(obj-vdso-y:%.o=$(obj)/%.o)
74
75$(obj-vdso): KBUILD_CFLAGS := $(cflags-vdso) $(native-abi)
76$(obj-vdso): KBUILD_AFLAGS := $(aflags-vdso) $(native-abi)
77
78$(obj)/vdso.lds: KBUILD_CPPFLAGS := $(ccflags-vdso) $(native-abi)
79
80$(obj)/vdso.so.dbg: $(obj)/vdso.lds $(obj-vdso) FORCE
81	$(call if_changed,vdsold_and_vdso_check)
82
83$(obj)/vdso.so: OBJCOPYFLAGS := -S
84$(obj)/vdso.so: $(obj)/vdso.so.dbg FORCE
85	$(call if_changed,objcopy)
86
87obj-y += vdso.o
88
89$(obj)/vdso.o : $(obj)/vdso.so
90
91# install commands for the unstripped file
92quiet_cmd_vdso_install = INSTALL $@
93      cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
94
95vdso.so: $(obj)/vdso.so.dbg
96	@mkdir -p $(MODLIB)/vdso
97	$(call cmd,vdso_install)
98
99vdso_install: vdso.so
100