| # SPDX-License-Identifier: GPL-2.0 |
| # |
| # Building a vDSO image for AArch64. |
| # |
| # Author: Will Deacon <will.deacon@arm.com> |
| # Heavily based on the vDSO Makefiles for other archs. |
| # |
| |
| # Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before |
| # the inclusion of generic Makefile. |
| ARCH_REL_TYPE_ABS := R_AARCH64_JUMP_SLOT|R_AARCH64_GLOB_DAT|R_AARCH64_ABS64 |
| include $(srctree)/lib/vdso/Makefile |
| |
| obj-vdso := vgettimeofday.o note.o sigreturn.o |
| |
| # Build rules |
| targets := $(obj-vdso) vdso.so vdso.so.dbg |
| obj-vdso := $(addprefix $(obj)/, $(obj-vdso)) |
| |
| btildflags-$(CONFIG_ARM64_BTI_KERNEL) += -z force-bti |
| |
| # -Bsymbolic has been added for consistency with arm, the compat vDSO and |
| # potential future proofing if we end up with internal calls to the exported |
| # routines, as x86 does (see 6f121e548f83 ("x86, vdso: Reimplement vdso.so |
| # preparation in build-time C")). |
| ldflags-y := -shared -soname=linux-vdso.so.1 --hash-style=sysv \ |
| -Bsymbolic --build-id=sha1 -n $(btildflags-y) -T |
| |
| ccflags-y := -fno-common -fno-builtin -fno-stack-protector -ffixed-x18 |
| ccflags-y += -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO |
| |
| # -Wmissing-prototypes and -Wmissing-declarations are removed from |
| # the CFLAGS of vgettimeofday.c to make possible to build the |
| # kernel with CONFIG_WERROR enabled. |
| CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS) \ |
| $(RANDSTRUCT_CFLAGS) $(GCC_PLUGINS_CFLAGS) \ |
| $(CC_FLAGS_LTO) -Wmissing-prototypes -Wmissing-declarations |
| KASAN_SANITIZE := n |
| KCSAN_SANITIZE := n |
| UBSAN_SANITIZE := n |
| OBJECT_FILES_NON_STANDARD := y |
| KCOV_INSTRUMENT := n |
| |
| CFLAGS_vgettimeofday.o = -O2 -mcmodel=tiny -fasynchronous-unwind-tables |
| |
| ifneq ($(c-gettimeofday-y),) |
| CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y) |
| endif |
| |
| # Disable gcov profiling for VDSO code |
| GCOV_PROFILE := n |
| |
| targets += vdso.lds |
| CPPFLAGS_vdso.lds += -P -C -U$(ARCH) |
| |
| # Link rule for the .so file, .lds has to be first |
| $(obj)/vdso.so.dbg: $(obj)/vdso.lds $(obj-vdso) FORCE |
| $(call if_changed,vdsold_and_vdso_check) |
| |
| # Strip rule for the .so file |
| $(obj)/%.so: OBJCOPYFLAGS := -S |
| $(obj)/%.so: $(obj)/%.so.dbg FORCE |
| $(call if_changed,objcopy) |
| |
| # Generate VDSO offsets using helper script |
| gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh |
| quiet_cmd_vdsosym = VDSOSYM $@ |
| cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@ |
| |
| include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE |
| $(call if_changed,vdsosym) |
| |
| # Actual build commands |
| quiet_cmd_vdsold_and_vdso_check = LD $@ |
| cmd_vdsold_and_vdso_check = $(cmd_ld); $(cmd_vdso_check) |
| |
| # Install commands for the unstripped file |
| quiet_cmd_vdso_install = INSTALL $@ |
| cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@ |
| |
| vdso.so: $(obj)/vdso.so.dbg |
| @mkdir -p $(MODLIB)/vdso |
| $(call cmd,vdso_install) |
| |
| vdso_install: vdso.so |