linux/arch/x86/purgatory/Makefile
Masahiro Yamada 9102fa3460 x86/purgatory: Remove -nostdlib compiler flag
The -nostdlib option requests the compiler to not use the standard
system startup files or libraries when linking. It is effective only
when $(CC) is used as a linker driver.

$(LD) is directly used for linking purgatory.{ro,chk} here, hence
-nostdlib is unneeded.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20211107162641.324688-2-masahiroy@kernel.org
2021-12-30 14:13:06 +01:00

85 lines
2.6 KiB
Makefile

# SPDX-License-Identifier: GPL-2.0
OBJECT_FILES_NON_STANDARD := y
purgatory-y := purgatory.o stack.o setup-x86_$(BITS).o sha256.o entry64.o string.o
targets += $(purgatory-y)
PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y))
$(obj)/string.o: $(srctree)/arch/x86/boot/compressed/string.c FORCE
$(call if_changed_rule,cc_o_c)
$(obj)/sha256.o: $(srctree)/lib/crypto/sha256.c FORCE
$(call if_changed_rule,cc_o_c)
CFLAGS_sha256.o := -D__DISABLE_EXPORTS
# When linking purgatory.ro with -r unresolved symbols are not checked,
# also link a purgatory.chk binary without -r to check for unresolved symbols.
PURGATORY_LDFLAGS := -e purgatory_start -z nodefaultlib
LDFLAGS_purgatory.ro := -r $(PURGATORY_LDFLAGS)
LDFLAGS_purgatory.chk := $(PURGATORY_LDFLAGS)
targets += purgatory.ro purgatory.chk
# Sanitizer, etc. runtimes are unavailable and cannot be linked here.
GCOV_PROFILE := n
KASAN_SANITIZE := n
UBSAN_SANITIZE := n
KCSAN_SANITIZE := n
KCOV_INSTRUMENT := n
# These are adjustments to the compiler flags used for objects that
# make up the standalone purgatory.ro
PURGATORY_CFLAGS_REMOVE := -mcmodel=kernel
PURGATORY_CFLAGS := -mcmodel=large -ffreestanding -fno-zero-initialized-in-bss -g0
PURGATORY_CFLAGS += $(DISABLE_STACKLEAK_PLUGIN) -DDISABLE_BRANCH_PROFILING
PURGATORY_CFLAGS += -fno-stack-protector
# Default KBUILD_CFLAGS can have -pg option set when FTRACE is enabled. That
# in turn leaves some undefined symbols like __fentry__ in purgatory and not
# sure how to relocate those.
ifdef CONFIG_FUNCTION_TRACER
PURGATORY_CFLAGS_REMOVE += $(CC_FLAGS_FTRACE)
endif
ifdef CONFIG_STACKPROTECTOR
PURGATORY_CFLAGS_REMOVE += -fstack-protector
endif
ifdef CONFIG_STACKPROTECTOR_STRONG
PURGATORY_CFLAGS_REMOVE += -fstack-protector-strong
endif
ifdef CONFIG_RETPOLINE
PURGATORY_CFLAGS_REMOVE += $(RETPOLINE_CFLAGS)
endif
CFLAGS_REMOVE_purgatory.o += $(PURGATORY_CFLAGS_REMOVE)
CFLAGS_purgatory.o += $(PURGATORY_CFLAGS)
CFLAGS_REMOVE_sha256.o += $(PURGATORY_CFLAGS_REMOVE)
CFLAGS_sha256.o += $(PURGATORY_CFLAGS)
CFLAGS_REMOVE_string.o += $(PURGATORY_CFLAGS_REMOVE)
CFLAGS_string.o += $(PURGATORY_CFLAGS)
AFLAGS_REMOVE_setup-x86_$(BITS).o += -Wa,-gdwarf-2
AFLAGS_REMOVE_entry64.o += -Wa,-gdwarf-2
$(obj)/purgatory.ro: $(PURGATORY_OBJS) FORCE
$(call if_changed,ld)
$(obj)/purgatory.chk: $(obj)/purgatory.ro FORCE
$(call if_changed,ld)
targets += kexec-purgatory.c
quiet_cmd_bin2c = BIN2C $@
cmd_bin2c = $(objtree)/scripts/bin2c kexec_purgatory < $< > $@
$(obj)/kexec-purgatory.c: $(obj)/purgatory.ro $(obj)/purgatory.chk FORCE
$(call if_changed,bin2c)
obj-$(CONFIG_KEXEC_FILE) += kexec-purgatory.o