xref: /openbmc/linux/arch/riscv/kernel/vdso/Makefile (revision 1c4b5ecb) 
1# SPDX-License-Identifier: GPL-2.0-only
2# Copied from arch/tile/kernel/vdso/Makefile
3
4# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
5# the inclusion of generic Makefile.
6ARCH_REL_TYPE_ABS := R_RISCV_32|R_RISCV_64|R_RISCV_JUMP_SLOT
7include $(srctree)/lib/vdso/Makefile
8# Symbols present in the vdso
9vdso-syms  = rt_sigreturn
10ifdef CONFIG_64BIT
11vdso-syms += vgettimeofday
12endif
13vdso-syms += getcpu
14vdso-syms += flush_icache
15
16# Files to link into the vdso
17obj-vdso = $(patsubst %, %.o, $(vdso-syms)) note.o
18
19ccflags-y := -fno-stack-protector
20
21ifneq ($(c-gettimeofday-y),)
22  CFLAGS_vgettimeofday.o += -fPIC -include $(c-gettimeofday-y)
23endif
24
25# Build rules
26targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.lds
27obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
28
29obj-y += vdso.o
30CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
31
32# Disable -pg to prevent insert call site
33CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os
34
35# Disable profiling and instrumentation for VDSO code
36GCOV_PROFILE := n
37KCOV_INSTRUMENT := n
38KASAN_SANITIZE := n
39UBSAN_SANITIZE := n
40
41# Force dependency
42$(obj)/vdso.o: $(obj)/vdso.so
43
44# link rule for the .so file, .lds has to be first
45$(obj)/vdso.so.dbg: $(obj)/vdso.lds $(obj-vdso) FORCE
46	$(call if_changed,vdsold)
47LDFLAGS_vdso.so.dbg = -shared -S -soname=linux-vdso.so.1 \
48	--build-id=sha1 --hash-style=both --eh-frame-hdr
49
50# strip rule for the .so file
51$(obj)/%.so: OBJCOPYFLAGS := -S
52$(obj)/%.so: $(obj)/%.so.dbg FORCE
53	$(call if_changed,objcopy)
54
55# Generate VDSO offsets using helper script
56gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh
57quiet_cmd_vdsosym = VDSOSYM $@
58	cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@
59
60include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
61	$(call if_changed,vdsosym)
62
63# actual build commands
64# The DSO images are built using a special linker script
65# Make sure only to export the intended __vdso_xxx symbol offsets.
66quiet_cmd_vdsold = VDSOLD  $@
67      cmd_vdsold = $(LD) $(ld_flags) -T $(filter-out FORCE,$^) -o $@.tmp && \
68                   $(OBJCOPY) $(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@ && \
69                   rm $@.tmp
70
71# install commands for the unstripped file
72quiet_cmd_vdso_install = INSTALL $@
73      cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
74
75vdso.so: $(obj)/vdso.so.dbg
76	@mkdir -p $(MODLIB)/vdso
77	$(call cmd,vdso_install)
78
79vdso_install: vdso.so
80