arch/x86/purgatory/Makefile

   1 # SPDX-License-Identifier: GPL-2.0
   2 OBJECT_FILES_NON_STANDARD := y
   3
   4 purgatory-y := purgatory.o stack.o setup-x86_$(BITS).o sha256.o entry64.o string.o
   5
   6 targets += $(purgatory-y)
   7 PURGATORY_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
  15 CFLAGS_sha256.o := -D__DISABLE_EXPORTS
  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.
  20 KBUILD_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.
  24 KBUILD_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.
  28 PURGATORY_LDFLAGS := -e purgatory_start -nostdlib -z nodefaultlib
  29 LDFLAGS_purgatory.ro := -r $(PURGATORY_LDFLAGS)
  30 LDFLAGS_purgatory.chk := $(PURGATORY_LDFLAGS)
  31 targets += purgatory.ro purgatory.chk
  32
  33 # Sanitizer, etc. runtimes are unavailable and cannot be linked here.
  34 GCOV_PROFILE    := n
  35 KASAN_SANITIZE  := n
  36 UBSAN_SANITIZE  := n
  37 KCSAN_SANITIZE  := n
  38 KCOV_INSTRUMENT := n
  39
  40 # These are adjustments to the compiler flags used for objects that
  41 # make up the standalone purgatory.ro
  42
  43 PURGATORY_CFLAGS_REMOVE := -mcmodel=kernel
  44 PURGATORY_CFLAGS := -mcmodel=large -ffreestanding -fno-zero-initialized-in-bss -g0
  45 PURGATORY_CFLAGS += $(DISABLE_STACKLEAK_PLUGIN) -DDISABLE_BRANCH_PROFILING
  46 PURGATORY_CFLAGS += -fno-stack-protector
  47
  48 # Default KBUILD_CFLAGS can have -pg option set when FTRACE is enabled. That
  49 # in turn leaves some undefined symbols like __fentry__ in purgatory and not
  50 # sure how to relocate those.
  51 ifdef CONFIG_FUNCTION_TRACER
  52 PURGATORY_CFLAGS_REMOVE         += $(CC_FLAGS_FTRACE)
  53 endif
  54
  55 ifdef CONFIG_STACKPROTECTOR
  56 PURGATORY_CFLAGS_REMOVE         += -fstack-protector
  57 endif
  58
  59 ifdef CONFIG_STACKPROTECTOR_STRONG
  60 PURGATORY_CFLAGS_REMOVE         += -fstack-protector-strong
  61 endif
  62
  63 ifdef CONFIG_RETPOLINE
  64 PURGATORY_CFLAGS_REMOVE         += $(RETPOLINE_CFLAGS)
  65 endif
  66
  67 CFLAGS_REMOVE_purgatory.o       += $(PURGATORY_CFLAGS_REMOVE)
  68 CFLAGS_purgatory.o              += $(PURGATORY_CFLAGS)
  69
  70 CFLAGS_REMOVE_sha256.o          += $(PURGATORY_CFLAGS_REMOVE)
  71 CFLAGS_sha256.o                 += $(PURGATORY_CFLAGS)
  72
  73 CFLAGS_REMOVE_string.o          += $(PURGATORY_CFLAGS_REMOVE)
  74 CFLAGS_string.o                 += $(PURGATORY_CFLAGS)
  75
  76 asflags-remove-y                += -g -Wa,-gdwarf-2
  77
  78 $(obj)/purgatory.ro: $(PURGATORY_OBJS) FORCE
  79                 $(call if_changed,ld)
  80
  81 $(obj)/purgatory.chk: $(obj)/purgatory.ro FORCE
  82                 $(call if_changed,ld)
  83
  84 targets += kexec-purgatory.c
  85
  86 quiet_cmd_bin2c = BIN2C   $@
  87       cmd_bin2c = $(objtree)/scripts/bin2c kexec_purgatory < $< > $@
  88
  89 $(obj)/kexec-purgatory.c: $(obj)/purgatory.ro $(obj)/purgatory.chk FORCE
  90         $(call if_changed,bin2c)
  91
  92 obj-$(CONFIG_KEXEC_FILE)        += kexec-purgatory.o