1 # SPDX-License-Identifier: GPL-2.0-only
2 # Copied from arch/tile/kernel/vdso/Makefile
4 # Include the generic Makefile to check the built vdso.
5 include $(srctree)/lib/vdso/Makefile
6 # Symbols present in the vdso
7 vdso-syms = rt_sigreturn
9 vdso-syms += vgettimeofday
12 vdso-syms += flush_icache
14 vdso-syms += sys_hwprobe
16 # Files to link into the vdso
17 obj-vdso = $(patsubst %, %.o, $(vdso-syms)) note.o
19 ccflags-y := -fno-stack-protector
20 ccflags-y += -DDISABLE_BRANCH_PROFILING
22 ifneq ($(c-gettimeofday-y),)
23 CFLAGS_vgettimeofday.o += -fPIC -include $(c-gettimeofday-y)
26 CFLAGS_hwprobe.o += -fPIC
29 targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.lds
30 obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
33 CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
34 ifneq ($(filter vgettimeofday, $(vdso-syms)),)
35 CPPFLAGS_vdso.lds += -DHAS_VGETTIMEOFDAY
38 # Disable -pg to prevent insert call site
39 CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS)
40 CFLAGS_REMOVE_hwprobe.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS)
42 # Disable profiling and instrumentation for VDSO code
49 $(obj)/vdso.o: $(obj)/vdso.so
51 # link rule for the .so file, .lds has to be first
52 $(obj)/vdso.so.dbg: $(obj)/vdso.lds $(obj-vdso) FORCE
53 $(call if_changed,vdsold)
54 LDFLAGS_vdso.so.dbg = -shared -S -soname=linux-vdso.so.1 \
55 --build-id=sha1 --hash-style=both --eh-frame-hdr
57 # strip rule for the .so file
58 $(obj)/%.so: OBJCOPYFLAGS := -S
59 $(obj)/%.so: $(obj)/%.so.dbg FORCE
60 $(call if_changed,objcopy)
62 # Generate VDSO offsets using helper script
63 gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh
64 quiet_cmd_vdsosym = VDSOSYM $@
65 cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@
67 include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
68 $(call if_changed,vdsosym)
70 # actual build commands
71 # The DSO images are built using a special linker script
72 # Make sure only to export the intended __vdso_xxx symbol offsets.
73 quiet_cmd_vdsold = VDSOLD $@
74 cmd_vdsold = $(LD) $(ld_flags) -T $(filter-out FORCE,$^) -o $@.tmp && \
75 $(OBJCOPY) $(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@ && \