1# SPDX-License-Identifier: GPL-2.0 2OBJECT_FILES_NON_STANDARD := y 3 4purgatory-y := purgatory.o stack.o setup-x86_$(BITS).o sha256.o entry64.o string.o 5 6targets += $(purgatory-y) 7PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y)) 8 9$(obj)/string.o: $(srctree)/arch/x86/boot/compressed/string.c FORCE 10 $(call if_changed_rule,cc_o_c) 11 12$(obj)/sha256.o: $(srctree)/lib/crypto/sha256.c FORCE 13 $(call if_changed_rule,cc_o_c) 14 15CFLAGS_sha256.o := -D__DISABLE_EXPORTS -D__NO_FORTIFY 16 17# When profile-guided optimization is enabled, llvm emits two different 18# overlapping text sections, which is not supported by kexec. Remove profile 19# optimization flags. 20KBUILD_CFLAGS := $(filter-out -fprofile-sample-use=% -fprofile-use=%,$(KBUILD_CFLAGS)) 21 22# When LTO is enabled, llvm emits many text sections, which is not supported 23# by kexec. Remove -flto=* flags. 24KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_LTO),$(KBUILD_CFLAGS)) 25 26# When linking purgatory.ro with -r unresolved symbols are not checked, 27# also link a purgatory.chk binary without -r to check for unresolved symbols. 28PURGATORY_LDFLAGS := -e purgatory_start -z nodefaultlib 29LDFLAGS_purgatory.ro := -r $(PURGATORY_LDFLAGS) 30LDFLAGS_purgatory.chk := $(PURGATORY_LDFLAGS) 31targets += purgatory.ro purgatory.chk 32 33# Sanitizer, etc. runtimes are unavailable and cannot be linked here. 34GCOV_PROFILE := n 35KASAN_SANITIZE := n 36UBSAN_SANITIZE := n 37KCSAN_SANITIZE := n 38KMSAN_SANITIZE := n 39KCOV_INSTRUMENT := n 40 41# These are adjustments to the compiler flags used for objects that 42# make up the standalone purgatory.ro 43 44PURGATORY_CFLAGS_REMOVE := -mcmodel=kernel 45PURGATORY_CFLAGS := -mcmodel=small -ffreestanding -fno-zero-initialized-in-bss -g0 46PURGATORY_CFLAGS += -fpic -fvisibility=hidden 47PURGATORY_CFLAGS += $(DISABLE_STACKLEAK_PLUGIN) -DDISABLE_BRANCH_PROFILING 48PURGATORY_CFLAGS += -fno-stack-protector 49 50# Default KBUILD_CFLAGS can have -pg option set when FTRACE is enabled. That 51# in turn leaves some undefined symbols like __fentry__ in purgatory and not 52# sure how to relocate those. 53ifdef CONFIG_FUNCTION_TRACER 54PURGATORY_CFLAGS_REMOVE += $(CC_FLAGS_FTRACE) 55endif 56 57ifdef CONFIG_STACKPROTECTOR 58PURGATORY_CFLAGS_REMOVE += -fstack-protector 59endif 60 61ifdef CONFIG_STACKPROTECTOR_STRONG 62PURGATORY_CFLAGS_REMOVE += -fstack-protector-strong 63endif 64 65ifdef CONFIG_RETPOLINE 66PURGATORY_CFLAGS_REMOVE += $(RETPOLINE_CFLAGS) 67endif 68 69ifdef CONFIG_CFI_CLANG 70PURGATORY_CFLAGS_REMOVE += $(CC_FLAGS_CFI) 71endif 72 73CFLAGS_REMOVE_purgatory.o += $(PURGATORY_CFLAGS_REMOVE) 74CFLAGS_purgatory.o += $(PURGATORY_CFLAGS) 75 76CFLAGS_REMOVE_sha256.o += $(PURGATORY_CFLAGS_REMOVE) 77CFLAGS_sha256.o += $(PURGATORY_CFLAGS) 78 79CFLAGS_REMOVE_string.o += $(PURGATORY_CFLAGS_REMOVE) 80CFLAGS_string.o += $(PURGATORY_CFLAGS) 81 82asflags-remove-y += $(foreach x, -g -gdwarf-4 -gdwarf-5, $(x) -Wa,$(x)) 83 84$(obj)/purgatory.ro: $(PURGATORY_OBJS) FORCE 85 $(call if_changed,ld) 86 87$(obj)/purgatory.chk: $(obj)/purgatory.ro FORCE 88 $(call if_changed,ld) 89 90$(obj)/kexec-purgatory.o: $(obj)/purgatory.ro $(obj)/purgatory.chk 91 92obj-y += kexec-purgatory.o 93