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