187f3248cSGuo Ren# SPDX-License-Identifier: GPL-2.0-only 287f3248cSGuo Ren 3*aff69273SFangrui Song# Include the generic Makefile to check the built vdso. 487f3248cSGuo Reninclude $(srctree)/lib/vdso/Makefile 587f3248cSGuo Ren 687f3248cSGuo Ren# Symbols present in the vdso 70d3b051aSGuo Renvdso-syms += rt_sigreturn 80d3b051aSGuo Renvdso-syms += vgettimeofday 987f3248cSGuo Ren 1087f3248cSGuo Ren# Files to link into the vdso 1187f3248cSGuo Renobj-vdso = $(patsubst %, %.o, $(vdso-syms)) note.o 1287f3248cSGuo Ren 130d3b051aSGuo Renifneq ($(c-gettimeofday-y),) 140d3b051aSGuo Ren CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y) 150d3b051aSGuo Renendif 160d3b051aSGuo Ren 170d3b051aSGuo Renccflags-y := -fno-stack-protector -DBUILD_VDSO32 1887f3248cSGuo Ren 1987f3248cSGuo Ren# Build rules 2087f3248cSGuo Rentargets := $(obj-vdso) vdso.so vdso.so.dbg vdso.lds vdso-dummy.o 2187f3248cSGuo Renobj-vdso := $(addprefix $(obj)/, $(obj-vdso)) 2287f3248cSGuo Ren 2387f3248cSGuo Renobj-y += vdso.o vdso-syms.o 2487f3248cSGuo RenCPPFLAGS_vdso.lds += -P -C -U$(ARCH) 2587f3248cSGuo Ren 2687f3248cSGuo Ren# Disable gcov profiling for VDSO code 2787f3248cSGuo RenGCOV_PROFILE := n 2887f3248cSGuo RenKCOV_INSTRUMENT := n 2987f3248cSGuo Ren 3087f3248cSGuo Ren# Force dependency 3187f3248cSGuo Ren$(obj)/vdso.o: $(obj)/vdso.so 3287f3248cSGuo Ren 3387f3248cSGuo RenSYSCFLAGS_vdso.so.dbg = $(c_flags) 3487f3248cSGuo Ren$(obj)/vdso.so.dbg: $(src)/vdso.lds $(obj-vdso) FORCE 3587f3248cSGuo Ren $(call if_changed,vdsold) 3687f3248cSGuo RenSYSCFLAGS_vdso.so.dbg = -shared -s -Wl,-soname=linux-vdso.so.1 \ 3787f3248cSGuo Ren -Wl,--build-id=sha1 -Wl,--hash-style=both 3887f3248cSGuo Ren 3987f3248cSGuo Ren$(obj)/vdso-syms.S: $(obj)/vdso.so FORCE 4087f3248cSGuo Ren $(call if_changed,so2s) 4187f3248cSGuo Ren 4287f3248cSGuo Ren# strip rule for the .so file 4387f3248cSGuo Ren$(obj)/%.so: OBJCOPYFLAGS := -S 4487f3248cSGuo Ren$(obj)/%.so: $(obj)/%.so.dbg FORCE 4587f3248cSGuo Ren $(call if_changed,objcopy) 4687f3248cSGuo Ren 4787f3248cSGuo Ren# actual build commands 4887f3248cSGuo Ren# The DSO images are built using a special linker script 4987f3248cSGuo Ren# Make sure only to export the intended __vdso_xxx symbol offsets. 5087f3248cSGuo Renquiet_cmd_vdsold = VDSOLD $@ 5187f3248cSGuo Ren cmd_vdsold = $(CC) $(KBUILD_CFLAGS) $(call cc-option, -no-pie) -nostdlib -nostartfiles $(SYSCFLAGS_$(@F)) \ 5287f3248cSGuo Ren -Wl,-T,$(filter-out FORCE,$^) -o $@.tmp && \ 5387f3248cSGuo Ren $(CROSS_COMPILE)objcopy \ 5487f3248cSGuo Ren $(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@ && \ 5587f3248cSGuo Ren rm $@.tmp 5687f3248cSGuo Ren 5787f3248cSGuo Ren# Extracts symbol offsets from the VDSO, converting them into an assembly file 5887f3248cSGuo Ren# that contains the same symbols at the same offsets. 5987f3248cSGuo Renquiet_cmd_so2s = SO2S $@ 6087f3248cSGuo Ren cmd_so2s = $(NM) -D $< | $(srctree)/$(src)/so2s.sh > $@ 6187f3248cSGuo Ren 6287f3248cSGuo Ren# install commands for the unstripped file 6387f3248cSGuo Renquiet_cmd_vdso_install = INSTALL $@ 6487f3248cSGuo Ren cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@ 6587f3248cSGuo Ren 6687f3248cSGuo Renvdso.so: $(obj)/vdso.so.dbg 6787f3248cSGuo Ren @mkdir -p $(MODLIB)/vdso 6887f3248cSGuo Ren $(call cmd,vdso_install) 6987f3248cSGuo Ren 7087f3248cSGuo Renvdso_install: vdso.so 71