xref: /linux/arch/x86/boot/startup/Makefile (revision 22bdd6e68bbe270a916233ec5f34a13ae5e80ed9)
1# SPDX-License-Identifier: GPL-2.0
2
3KBUILD_AFLAGS		+= -D__DISABLE_EXPORTS
4KBUILD_CFLAGS		+= -D__DISABLE_EXPORTS -mcmodel=small -fPIC \
5			   -Os -DDISABLE_BRANCH_PROFILING \
6			   $(DISABLE_STACKLEAK_PLUGIN) \
7			   $(DISABLE_LATENT_ENTROPY_PLUGIN) \
8			   -fno-stack-protector -D__NO_FORTIFY \
9			   -fno-jump-tables \
10			   -include $(srctree)/include/linux/hidden.h
11
12# disable ftrace hooks and LTO
13KBUILD_CFLAGS	:= $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS))
14KBUILD_CFLAGS	:= $(filter-out $(CC_FLAGS_LTO),$(KBUILD_CFLAGS))
15KASAN_SANITIZE	:= n
16KCSAN_SANITIZE	:= n
17KMSAN_SANITIZE	:= n
18UBSAN_SANITIZE	:= n
19KCOV_INSTRUMENT	:= n
20
21obj-$(CONFIG_X86_64)		+= gdt_idt.o map_kernel.o
22obj-$(CONFIG_AMD_MEM_ENCRYPT)	+= sme.o sev-startup.o
23pi-objs				:= $(patsubst %.o,$(obj)/%.o,$(obj-y))
24
25lib-$(CONFIG_X86_64)		+= la57toggle.o
26lib-$(CONFIG_EFI_MIXED)		+= efi-mixed.o
27
28#
29# Disable objtool validation for all library code, which is intended
30# to be linked into the decompressor or the EFI stub but not vmlinux
31#
32$(patsubst %.o,$(obj)/%.o,$(lib-y)): OBJECT_FILES_NON_STANDARD := y
33
34#
35# Invoke objtool for each object individually to check for absolute
36# relocations, even if other objtool actions are being deferred.
37#
38$(pi-objs): objtool-enabled	= 1
39$(pi-objs): objtool-args	= $(if $(delay-objtool),,$(objtool-args-y)) --noabs
40
41#
42# Confine the startup code by prefixing all symbols with __pi_ (for position
43# independent). This ensures that startup code can only call other startup
44# code, or code that has explicitly been made accessible to it via a symbol
45# alias.
46#
47$(obj)/%.pi.o: OBJCOPYFLAGS := --prefix-symbols=__pi_
48$(obj)/%.pi.o: $(obj)/%.o FORCE
49	$(call if_changed,objcopy)
50
51targets	+= $(obj-y)
52obj-y	:= $(patsubst %.o,%.pi.o,$(obj-y))
53