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, $(vdso-syms)) note.o 18 19ccflags-y := -fno-stack-protector 20ccflags-y += -DDISABLE_BRANCH_PROFILING 21 22ifneq ($(c-gettimeofday-y),) 23 CFLAGS_vgettimeofday.o += -fPIC -include $(c-gettimeofday-y) 24endif 25 26# Build rules 27targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.lds vdso-syms.S 28obj-vdso := $(addprefix $(obj)/, $(obj-vdso)) 29 30obj-y += vdso.o vdso-syms.o 31CPPFLAGS_vdso.lds += -P -C -U$(ARCH) 32ifneq ($(filter vgettimeofday, $(vdso-syms)),) 33CPPFLAGS_vdso.lds += -DHAS_VGETTIMEOFDAY 34endif 35 36# Disable -pg to prevent insert call site 37CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) 38 39# Disable profiling and instrumentation for VDSO code 40GCOV_PROFILE := n 41KCOV_INSTRUMENT := n 42KASAN_SANITIZE := n 43 44# Force dependency 45$(obj)/vdso.o: $(obj)/vdso.so 46 47# link rule for the .so file, .lds has to be first 48$(obj)/vdso.so.dbg: $(obj)/vdso.lds $(obj-vdso) FORCE 49 $(call if_changed,vdsold) 50LDFLAGS_vdso.so.dbg = -shared -s -soname=linux-vdso.so.1 \ 51 --build-id=sha1 --hash-style=both --eh-frame-hdr 52 53# We also create a special relocatable object that should mirror the symbol 54# table and layout of the linked DSO. With ld --just-symbols we can then 55# refer to these symbols in the kernel code rather than hand-coded addresses. 56$(obj)/vdso-syms.S: $(obj)/vdso.so FORCE 57 $(call if_changed,so2s) 58 59# strip rule for the .so file 60$(obj)/%.so: OBJCOPYFLAGS := -S 61$(obj)/%.so: $(obj)/%.so.dbg FORCE 62 $(call if_changed,objcopy) 63 64# actual build commands 65# The DSO images are built using a special linker script 66# Make sure only to export the intended __vdso_xxx symbol offsets. 67quiet_cmd_vdsold = VDSOLD $@ 68 cmd_vdsold = $(LD) $(ld_flags) -T $(filter-out FORCE,$^) -o $@.tmp && \ 69 $(OBJCOPY) $(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@ && \ 70 rm $@.tmp 71 72# Extracts symbol offsets from the VDSO, converting them into an assembly file 73# that contains the same symbols at the same offsets. 74quiet_cmd_so2s = SO2S $@ 75 cmd_so2s = $(NM) -D $< | $(srctree)/$(src)/so2s.sh > $@ 76 77# install commands for the unstripped file 78quiet_cmd_vdso_install = INSTALL $@ 79 cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@ 80 81vdso.so: $(obj)/vdso.so.dbg 82 @mkdir -p $(MODLIB)/vdso 83 $(call cmd,vdso_install) 84 85vdso_install: vdso.so 86