| # SPDX-License-Identifier: GPL-2.0 |
| # |
| # Building vDSO images for x86. |
| # |
| |
| # Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before |
| # the inclusion of generic Makefile. |
| ARCH_REL_TYPE_ABS := R_X86_64_JUMP_SLOT|R_X86_64_GLOB_DAT|R_X86_64_RELATIVE| |
| ARCH_REL_TYPE_ABS += R_386_GLOB_DAT|R_386_JMP_SLOT|R_386_RELATIVE |
| include $(srctree)/lib/vdso/Makefile |
| |
| KBUILD_CFLAGS += $(DISABLE_LTO) |
| |
| # Sanitizer runtimes are unavailable and cannot be linked here. |
| KASAN_SANITIZE := n |
| UBSAN_SANITIZE := n |
| KCSAN_SANITIZE := n |
| OBJECT_FILES_NON_STANDARD := y |
| |
| # Prevents link failures: __sanitizer_cov_trace_pc() is not linked in. |
| KCOV_INSTRUMENT := n |
| |
| VDSO64-$(CONFIG_X86_64) := y |
| VDSOX32-$(CONFIG_X86_X32_ABI) := y |
| VDSO32-$(CONFIG_X86_32) := y |
| VDSO32-$(CONFIG_IA32_EMULATION) := y |
| |
| # files to link into the vdso |
| vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o |
| vobjs32-y := vdso32/note.o vdso32/system_call.o vdso32/sigreturn.o |
| vobjs32-y += vdso32/vclock_gettime.o |
| |
| # files to link into kernel |
| obj-y += vma.o |
| KASAN_SANITIZE_vma.o := y |
| UBSAN_SANITIZE_vma.o := y |
| KCSAN_SANITIZE_vma.o := y |
| OBJECT_FILES_NON_STANDARD_vma.o := n |
| |
| # vDSO images to build |
| vdso_img-$(VDSO64-y) += 64 |
| vdso_img-$(VDSOX32-y) += x32 |
| vdso_img-$(VDSO32-y) += 32 |
| |
| obj-$(VDSO32-y) += vdso32-setup.o |
| |
| vobjs := $(foreach F,$(vobjs-y),$(obj)/$F) |
| vobjs32 := $(foreach F,$(vobjs32-y),$(obj)/$F) |
| |
| $(obj)/vdso.o: $(obj)/vdso.so |
| |
| targets += vdso.lds $(vobjs-y) |
| targets += vdso32/vdso32.lds $(vobjs32-y) |
| |
| # Build the vDSO image C files and link them in. |
| vdso_img_objs := $(vdso_img-y:%=vdso-image-%.o) |
| vdso_img_cfiles := $(vdso_img-y:%=vdso-image-%.c) |
| vdso_img_sodbg := $(vdso_img-y:%=vdso%.so.dbg) |
| obj-y += $(vdso_img_objs) |
| targets += $(vdso_img_cfiles) |
| targets += $(vdso_img_sodbg) $(vdso_img-y:%=vdso%.so) |
| |
| CPPFLAGS_vdso.lds += -P -C |
| |
| VDSO_LDFLAGS_vdso.lds = -m elf_x86_64 -soname linux-vdso.so.1 --no-undefined \ |
| -z max-page-size=4096 |
| |
| $(obj)/vdso64.so.dbg: $(obj)/vdso.lds $(vobjs) FORCE |
| $(call if_changed,vdso_and_check) |
| |
| HOST_EXTRACFLAGS += -I$(srctree)/tools/include -I$(srctree)/include/uapi -I$(srctree)/arch/$(SUBARCH)/include/uapi |
| hostprogs += vdso2c |
| |
| quiet_cmd_vdso2c = VDSO2C $@ |
| cmd_vdso2c = $(obj)/vdso2c $< $(<:%.dbg=%) $@ |
| |
| $(obj)/vdso-image-%.c: $(obj)/vdso%.so.dbg $(obj)/vdso%.so $(obj)/vdso2c FORCE |
| $(call if_changed,vdso2c) |
| |
| # |
| # Don't omit frame pointers for ease of userspace debugging, but do |
| # optimize sibling calls. |
| # |
| CFL := $(PROFILING) -mcmodel=small -fPIC -O2 -fasynchronous-unwind-tables -m64 \ |
| $(filter -g%,$(KBUILD_CFLAGS)) $(call cc-option, -fno-stack-protector) \ |
| -fno-omit-frame-pointer -foptimize-sibling-calls \ |
| -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO |
| |
| ifdef CONFIG_RETPOLINE |
| ifneq ($(RETPOLINE_VDSO_CFLAGS),) |
| CFL += $(RETPOLINE_VDSO_CFLAGS) |
| endif |
| endif |
| |
| $(vobjs): KBUILD_CFLAGS := $(filter-out $(GCC_PLUGINS_CFLAGS) $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS)) $(CFL) |
| |
| # |
| # vDSO code runs in userspace and -pg doesn't help with profiling anyway. |
| # |
| CFLAGS_REMOVE_vclock_gettime.o = -pg |
| CFLAGS_REMOVE_vdso32/vclock_gettime.o = -pg |
| CFLAGS_REMOVE_vgetcpu.o = -pg |
| |
| # |
| # X32 processes use x32 vDSO to access 64bit kernel data. |
| # |
| # Build x32 vDSO image: |
| # 1. Compile x32 vDSO as 64bit. |
| # 2. Convert object files to x32. |
| # 3. Build x32 VDSO image with x32 objects, which contains 64bit codes |
| # so that it can reach 64bit address space with 64bit pointers. |
| # |
| |
| CPPFLAGS_vdsox32.lds = $(CPPFLAGS_vdso.lds) |
| VDSO_LDFLAGS_vdsox32.lds = -m elf32_x86_64 -soname linux-vdso.so.1 \ |
| -z max-page-size=4096 |
| |
| # x32-rebranded versions |
| vobjx32s-y := $(vobjs-y:.o=-x32.o) |
| |
| # same thing, but in the output directory |
| vobjx32s := $(foreach F,$(vobjx32s-y),$(obj)/$F) |
| |
| # Convert 64bit object file to x32 for x32 vDSO. |
| quiet_cmd_x32 = X32 $@ |
| cmd_x32 = $(OBJCOPY) -O elf32-x86-64 $< $@ |
| |
| $(obj)/%-x32.o: $(obj)/%.o FORCE |
| $(call if_changed,x32) |
| |
| targets += vdsox32.lds $(vobjx32s-y) |
| |
| $(obj)/%.so: OBJCOPYFLAGS := -S |
| $(obj)/%.so: $(obj)/%.so.dbg FORCE |
| $(call if_changed,objcopy) |
| |
| $(obj)/vdsox32.so.dbg: $(obj)/vdsox32.lds $(vobjx32s) FORCE |
| $(call if_changed,vdso_and_check) |
| |
| CPPFLAGS_vdso32/vdso32.lds = $(CPPFLAGS_vdso.lds) |
| VDSO_LDFLAGS_vdso32.lds = -m elf_i386 -soname linux-gate.so.1 |
| |
| KBUILD_AFLAGS_32 := $(filter-out -m64,$(KBUILD_AFLAGS)) -DBUILD_VDSO |
| $(obj)/vdso32.so.dbg: KBUILD_AFLAGS = $(KBUILD_AFLAGS_32) |
| $(obj)/vdso32.so.dbg: asflags-$(CONFIG_X86_64) += -m32 |
| |
| KBUILD_CFLAGS_32 := $(filter-out -m64,$(KBUILD_CFLAGS)) |
| KBUILD_CFLAGS_32 := $(filter-out -mcmodel=kernel,$(KBUILD_CFLAGS_32)) |
| KBUILD_CFLAGS_32 := $(filter-out -fno-pic,$(KBUILD_CFLAGS_32)) |
| KBUILD_CFLAGS_32 := $(filter-out -mfentry,$(KBUILD_CFLAGS_32)) |
| KBUILD_CFLAGS_32 := $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS_32)) |
| KBUILD_CFLAGS_32 := $(filter-out $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS_32)) |
| KBUILD_CFLAGS_32 += -m32 -msoft-float -mregparm=0 -fpic |
| KBUILD_CFLAGS_32 += $(call cc-option, -fno-stack-protector) |
| KBUILD_CFLAGS_32 += $(call cc-option, -foptimize-sibling-calls) |
| KBUILD_CFLAGS_32 += -fno-omit-frame-pointer |
| KBUILD_CFLAGS_32 += -DDISABLE_BRANCH_PROFILING |
| |
| ifdef CONFIG_RETPOLINE |
| ifneq ($(RETPOLINE_VDSO_CFLAGS),) |
| KBUILD_CFLAGS_32 += $(RETPOLINE_VDSO_CFLAGS) |
| endif |
| endif |
| |
| $(obj)/vdso32.so.dbg: KBUILD_CFLAGS = $(KBUILD_CFLAGS_32) |
| |
| $(obj)/vdso32.so.dbg: $(obj)/vdso32/vdso32.lds $(vobjs32) FORCE |
| $(call if_changed,vdso_and_check) |
| |
| # |
| # The DSO images are built using a special linker script. |
| # |
| quiet_cmd_vdso = VDSO $@ |
| cmd_vdso = $(LD) -nostdlib -o $@ \ |
| $(VDSO_LDFLAGS) $(VDSO_LDFLAGS_$(filter %.lds,$(^F))) \ |
| -T $(filter %.lds,$^) $(filter %.o,$^) && \ |
| sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@' |
| |
| VDSO_LDFLAGS = -shared --hash-style=both --build-id \ |
| $(call ld-option, --eh-frame-hdr) -Bsymbolic |
| GCOV_PROFILE := n |
| |
| quiet_cmd_vdso_and_check = VDSO $@ |
| cmd_vdso_and_check = $(cmd_vdso); $(cmd_vdso_check) |
| |
| # |
| # Install the unstripped copies of vdso*.so. If our toolchain supports |
| # build-id, install .build-id links as well. |
| # |
| quiet_cmd_vdso_install = INSTALL $(@:install_%=%) |
| define cmd_vdso_install |
| cp $< "$(MODLIB)/vdso/$(@:install_%=%)"; \ |
| if readelf -n $< |grep -q 'Build ID'; then \ |
| buildid=`readelf -n $< |grep 'Build ID' |sed -e 's/^.*Build ID: \(.*\)$$/\1/'`; \ |
| first=`echo $$buildid | cut -b-2`; \ |
| last=`echo $$buildid | cut -b3-`; \ |
| mkdir -p "$(MODLIB)/vdso/.build-id/$$first"; \ |
| ln -sf "../../$(@:install_%=%)" "$(MODLIB)/vdso/.build-id/$$first/$$last.debug"; \ |
| fi |
| endef |
| |
| vdso_img_insttargets := $(vdso_img_sodbg:%.dbg=install_%) |
| |
| $(MODLIB)/vdso: FORCE |
| @mkdir -p $(MODLIB)/vdso |
| |
| $(vdso_img_insttargets): install_%: $(obj)/%.dbg $(MODLIB)/vdso |
| $(call cmd,vdso_install) |
| |
| PHONY += vdso_install $(vdso_img_insttargets) |
| vdso_install: $(vdso_img_insttargets) |
| |
| clean-files := vdso32.so vdso32.so.dbg vdso64* vdso-image-*.c vdsox32.so* |
