1# SPDX-License-Identifier: GPL-2.0 2# Objects to go into the VDSO. 3 4# Include the generic Makefile to check the built vdso. 5include $(srctree)/lib/vdso/Makefile.include 6 7obj-vdso-y := elf.o vgetcpu.o vgetrandom.o \ 8 vgetrandom-chacha.o sigreturn.o 9obj-vdso-$(CONFIG_GENERIC_GETTIMEOFDAY) += vgettimeofday.o 10 11# Common compiler flags between ABIs. 12ccflags-vdso := \ 13 $(filter -I%,$(KBUILD_CFLAGS)) \ 14 $(filter -E%,$(KBUILD_CFLAGS)) \ 15 $(filter -m32,$(KBUILD_CFLAGS)) \ 16 $(filter -m64,$(KBUILD_CFLAGS)) \ 17 $(filter -march=%,$(KBUILD_CFLAGS)) \ 18 $(filter -m%-float,$(KBUILD_CFLAGS)) \ 19 $(CONFIG_CC_OPT_INLINE_MEMSET) \ 20 $(CLANG_FLAGS) \ 21 -D__VDSO__ 22 23ifdef CONFIG_32BIT 24ccflags-vdso += -DBUILD_VDSO32 25endif 26 27cflags-vdso := $(ccflags-vdso) \ 28 -isystem $(shell $(CC) -print-file-name=include) \ 29 $(filter -W%,$(filter-out -Wa$(comma)%,$(KBUILD_CFLAGS))) \ 30 $(CC_FLAGS_DIALECT) -O2 -g -fno-strict-aliasing -fno-common -fno-builtin \ 31 -fno-stack-protector -fno-jump-tables -DDISABLE_BRANCH_PROFILING \ 32 $(call cc-option, -fasynchronous-unwind-tables) \ 33 $(call cc-option, -fno-stack-protector) 34aflags-vdso := $(ccflags-vdso) \ 35 -D__ASSEMBLY__ -Wa,-gdwarf-2 36 37ifneq ($(c-gettimeofday-y),) 38 CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y) 39endif 40 41ifneq ($(c-getrandom-y),) 42 CFLAGS_vgetrandom.o += -include $(c-getrandom-y) 43endif 44 45# VDSO linker flags. 46ldflags-y := -Bsymbolic --no-undefined -soname=linux-vdso.so.1 \ 47 $(filter -E%,$(KBUILD_CFLAGS)) -shared --build-id --eh-frame-hdr -T 48 49# 50# Shared build commands. 51# 52 53quiet_cmd_vdsold_and_vdso_check = LD $@ 54 cmd_vdsold_and_vdso_check = $(cmd_ld); $(cmd_vdso_check) 55 56quiet_cmd_vdsoas_o_S = AS $@ 57 cmd_vdsoas_o_S = $(CC) $(a_flags) -c -o $@ $< 58 59# Generate VDSO offsets using helper script 60gen-vdsosym := $(src)/gen_vdso_offsets.sh 61quiet_cmd_vdsosym = VDSOSYM $@ 62 cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@ 63 64include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE 65 $(call if_changed,vdsosym) 66 67# 68# Build native VDSO. 69# 70 71native-abi := $(filter -mabi=%,$(KBUILD_CFLAGS)) 72 73targets += $(obj-vdso-y) 74targets += vdso.lds vdso.so.dbg vdso.so 75 76obj-vdso := $(obj-vdso-y:%.o=$(obj)/%.o) 77 78$(obj-vdso): KBUILD_CFLAGS := $(cflags-vdso) $(native-abi) 79$(obj-vdso): KBUILD_AFLAGS := $(aflags-vdso) $(native-abi) 80 81$(obj)/vdso.lds: KBUILD_CPPFLAGS := $(ccflags-vdso) $(native-abi) 82 83$(obj)/vdso.so.dbg: $(obj)/vdso.lds $(obj-vdso) FORCE 84 $(call if_changed,vdsold_and_vdso_check) 85 86$(obj)/vdso.so: OBJCOPYFLAGS := -S 87$(obj)/vdso.so: $(obj)/vdso.so.dbg FORCE 88 $(call if_changed,objcopy) 89 90obj-y += vdso.o 91 92$(obj)/vdso.o : $(obj)/vdso.so 93