1# SPDX-License-Identifier: GPL-2.0 2 3# Finds the multi-part object the current object will be linked into. 4# If the object belongs to two or more multi-part objects, list them all. 5modname-multi = $(sort $(foreach m,$(multi-obj-ym),\ 6 $(if $(filter $*.o, $(call suffix-search, $m, .o, -objs -y -m)),$(m:.o=)))) 7 8__modname = $(or $(modname-multi),$(basetarget)) 9 10modname = $(subst $(space),:,$(__modname)) 11modfile = $(addprefix $(obj)/,$(__modname)) 12 13# target with $(obj)/ and its suffix stripped 14target-stem = $(basename $(patsubst $(obj)/%,%,$@)) 15 16# These flags are needed for modversions and compiling, so we define them here 17# $(modname_flags) defines KBUILD_MODNAME as the name of the module it will 18# end up in (or would, if it gets compiled in) 19name-fix-token = $(subst $(comma),_,$(subst -,_,$1)) 20name-fix = $(call stringify,$(call name-fix-token,$1)) 21basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget)) 22modname_flags = -DKBUILD_MODNAME=$(call name-fix,$(modname)) \ 23 -D__KBUILD_MODNAME=kmod_$(call name-fix-token,$(modname)) 24modfile_flags = -DKBUILD_MODFILE=$(call stringify,$(modfile)) 25 26_c_flags = $(filter-out $(CFLAGS_REMOVE_$(target-stem).o), \ 27 $(filter-out $(ccflags-remove-y), \ 28 $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(ccflags-y)) \ 29 $(CFLAGS_$(target-stem).o)) 30_rust_flags = $(filter-out $(RUSTFLAGS_REMOVE_$(target-stem).o), \ 31 $(filter-out $(rustflags-remove-y), \ 32 $(KBUILD_RUSTFLAGS) $(rustflags-y)) \ 33 $(RUSTFLAGS_$(target-stem).o)) 34_a_flags = $(filter-out $(AFLAGS_REMOVE_$(target-stem).o), \ 35 $(filter-out $(asflags-remove-y), \ 36 $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) $(asflags-y)) \ 37 $(AFLAGS_$(target-stem).o)) 38_cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(target-stem).lds) 39 40# 41# Enable gcov profiling flags for a file, directory or for all files depending 42# on variables GCOV_PROFILE_obj.o, GCOV_PROFILE and CONFIG_GCOV_PROFILE_ALL 43# (in this order) 44# 45ifeq ($(CONFIG_GCOV_KERNEL),y) 46_c_flags += $(if $(patsubst n%,, \ 47 $(GCOV_PROFILE_$(target-stem).o)$(GCOV_PROFILE)$(if $(is-kernel-object),$(CONFIG_GCOV_PROFILE_ALL))), \ 48 $(CFLAGS_GCOV)) 49endif 50 51# 52# Enable address sanitizer flags for kernel except some files or directories 53# we don't want to check (depends on variables KASAN_SANITIZE_obj.o, KASAN_SANITIZE) 54# 55ifeq ($(CONFIG_KASAN),y) 56ifneq ($(CONFIG_KASAN_HW_TAGS),y) 57_c_flags += $(if $(patsubst n%,, \ 58 $(KASAN_SANITIZE_$(target-stem).o)$(KASAN_SANITIZE)$(is-kernel-object)), \ 59 $(CFLAGS_KASAN), $(CFLAGS_KASAN_NOSANITIZE)) 60_rust_flags += $(if $(patsubst n%,, \ 61 $(KASAN_SANITIZE_$(target-stem).o)$(KASAN_SANITIZE)$(is-kernel-object)), \ 62 $(RUSTFLAGS_KASAN)) 63endif 64endif 65 66ifeq ($(CONFIG_KMSAN),y) 67_c_flags += $(if $(patsubst n%,, \ 68 $(KMSAN_SANITIZE_$(target-stem).o)$(KMSAN_SANITIZE)$(is-kernel-object)), \ 69 $(CFLAGS_KMSAN)) 70_c_flags += $(if $(patsubst n%,, \ 71 $(KMSAN_ENABLE_CHECKS_$(target-stem).o)$(KMSAN_ENABLE_CHECKS)$(is-kernel-object)), \ 72 , -mllvm -msan-disable-checks=1) 73endif 74 75ifeq ($(CONFIG_UBSAN),y) 76_c_flags += $(if $(patsubst n%,, \ 77 $(UBSAN_SANITIZE_$(target-stem).o)$(UBSAN_SANITIZE)$(is-kernel-object)), \ 78 $(CFLAGS_UBSAN)) 79_c_flags += $(if $(patsubst n%,, \ 80 $(UBSAN_INTEGER_WRAP_$(target-stem).o)$(UBSAN_SANITIZE_$(target-stem).o)$(UBSAN_INTEGER_WRAP)$(UBSAN_SANITIZE)$(is-kernel-object)), \ 81 $(CFLAGS_UBSAN_INTEGER_WRAP)) 82endif 83 84ifeq ($(CONFIG_KCOV),y) 85_c_flags += $(if $(patsubst n%,, \ 86 $(KCOV_INSTRUMENT_$(target-stem).o)$(KCOV_INSTRUMENT)$(if $(is-kernel-object),$(CONFIG_KCOV_INSTRUMENT_ALL))), \ 87 $(CFLAGS_KCOV)) 88endif 89 90# 91# Enable KCSAN flags except some files or directories we don't want to check 92# (depends on variables KCSAN_SANITIZE_obj.o, KCSAN_SANITIZE) 93# 94ifeq ($(CONFIG_KCSAN),y) 95_c_flags += $(if $(patsubst n%,, \ 96 $(KCSAN_SANITIZE_$(target-stem).o)$(KCSAN_SANITIZE)$(is-kernel-object)), \ 97 $(CFLAGS_KCSAN)) 98# Some uninstrumented files provide implied barriers required to avoid false 99# positives: set KCSAN_INSTRUMENT_BARRIERS for barrier instrumentation only. 100_c_flags += $(if $(patsubst n%,, \ 101 $(KCSAN_INSTRUMENT_BARRIERS_$(target-stem).o)$(KCSAN_INSTRUMENT_BARRIERS)n), \ 102 -D__KCSAN_INSTRUMENT_BARRIERS__) 103endif 104 105# 106# Enable AutoFDO build flags except some files or directories we don't want to 107# enable (depends on variables AUTOFDO_PROFILE_obj.o and AUTOFDO_PROFILE). 108# 109ifeq ($(CONFIG_AUTOFDO_CLANG),y) 110_c_flags += $(if $(patsubst n%,, \ 111 $(AUTOFDO_PROFILE_$(target-stem).o)$(AUTOFDO_PROFILE)$(is-kernel-object)), \ 112 $(CFLAGS_AUTOFDO_CLANG)) 113endif 114 115# 116# Enable Propeller build flags except some files or directories we don't want to 117# enable (depends on variables AUTOFDO_PROPELLER_obj.o and PROPELLER_PROFILE). 118# 119ifdef CONFIG_PROPELLER_CLANG 120_c_flags += $(if $(patsubst n%,, \ 121 $(AUTOFDO_PROFILE_$(target-stem).o)$(AUTOFDO_PROFILE)$(PROPELLER_PROFILE))$(is-kernel-object), \ 122 $(CFLAGS_PROPELLER_CLANG)) 123endif 124 125# $(src) for including checkin headers from generated source files 126# $(obj) for including generated headers from checkin source files 127ifdef building_out_of_srctree 128_c_flags += $(addprefix -I, $(src) $(obj)) 129_a_flags += $(addprefix -I, $(src) $(obj)) 130_cpp_flags += $(addprefix -I, $(src) $(obj)) 131endif 132 133# If $(is-kernel-object) is 'y', this object will be linked to vmlinux or modules 134is-kernel-object = $(or $(part-of-builtin),$(part-of-module)) 135 136part-of-builtin = $(if $(filter $(basename $@).o, $(real-obj-y) $(lib-y)),y) 137part-of-module = $(if $(filter $(basename $@).o, $(real-obj-m)),y) 138quiet_modtag = $(if $(part-of-module),[M], ) 139 140modkern_cflags = \ 141 $(if $(part-of-module), \ 142 $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \ 143 $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL) $(modfile_flags)) 144 145modkern_rustflags = \ 146 $(if $(part-of-module), \ 147 $(KBUILD_RUSTFLAGS_MODULE) $(RUSTFLAGS_MODULE), \ 148 $(KBUILD_RUSTFLAGS_KERNEL) $(RUSTFLAGS_KERNEL)) 149 150modkern_aflags = $(if $(part-of-module), \ 151 $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE), \ 152 $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL) $(modfile_flags)) 153 154c_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ 155 -include $(srctree)/include/linux/compiler_types.h \ 156 $(_c_flags) $(modkern_cflags) \ 157 $(basename_flags) $(modname_flags) 158 159rust_flags = $(_rust_flags) $(modkern_rustflags) @$(objtree)/include/generated/rustc_cfg 160 161a_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ 162 $(_a_flags) $(modkern_aflags) $(modname_flags) 163 164cpp_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ 165 $(_cpp_flags) 166 167ld_flags = $(KBUILD_LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F)) 168 169ifdef CONFIG_OBJTOOL 170 171objtool := $(objtree)/tools/objtool/objtool 172 173objtool-args-$(CONFIG_HAVE_JUMP_LABEL_HACK) += --hacks=jump_label 174objtool-args-$(CONFIG_HAVE_NOINSTR_HACK) += --hacks=noinstr 175objtool-args-$(CONFIG_MITIGATION_CALL_DEPTH_TRACKING) += --hacks=skylake 176objtool-args-$(CONFIG_X86_KERNEL_IBT) += --ibt 177objtool-args-$(CONFIG_FINEIBT) += --cfi 178objtool-args-$(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL) += --mcount 179ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL 180objtool-args-$(CONFIG_HAVE_OBJTOOL_NOP_MCOUNT) += --mnop 181endif 182objtool-args-$(CONFIG_UNWINDER_ORC) += --orc 183objtool-args-$(CONFIG_MITIGATION_RETPOLINE) += --retpoline 184objtool-args-$(CONFIG_MITIGATION_RETHUNK) += --rethunk 185objtool-args-$(CONFIG_MITIGATION_SLS) += --sls 186objtool-args-$(CONFIG_STACK_VALIDATION) += --stackval 187objtool-args-$(CONFIG_HAVE_STATIC_CALL_INLINE) += --static-call 188objtool-args-$(CONFIG_HAVE_UACCESS_VALIDATION) += --uaccess 189objtool-args-$(or $(CONFIG_GCOV_KERNEL),$(CONFIG_KCOV)) += --no-unreachable 190objtool-args-$(CONFIG_PREFIX_SYMBOLS) += --prefix=$(CONFIG_FUNCTION_PADDING_BYTES) 191objtool-args-$(CONFIG_OBJTOOL_WERROR) += --Werror 192 193objtool-args = $(objtool-args-y) \ 194 $(if $(delay-objtool), --link) \ 195 $(if $(part-of-module), --module) 196 197delay-objtool := $(or $(CONFIG_LTO_CLANG),$(CONFIG_X86_KERNEL_IBT)) 198 199cmd_objtool = $(if $(objtool-enabled), ; $(objtool) $(objtool-args) $@) 200cmd_gen_objtooldep = $(if $(objtool-enabled), { echo ; echo '$@: $$(wildcard $(objtool))' ; } >> $(dot-target).cmd) 201 202objtool-enabled := y 203 204endif # CONFIG_OBJTOOL 205 206# Useful for describing the dependency of composite objects 207# Usage: 208# $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add) 209define multi_depend 210$(foreach m, $1, \ 211 $(eval $m: \ 212 $(addprefix $(obj)/, $(call suffix-search, $(patsubst $(obj)/%,%,$m), $2, $3)))) 213endef 214 215# Build commands 216# =========================================================================== 217# These are shared by some Makefile.* files. 218 219ifdef CONFIG_LTO_CLANG 220# Run $(LD) here to convert LLVM IR to ELF in the following cases: 221# - when this object needs objtool processing, as objtool cannot process LLVM IR 222# - when this is a single-object module, as modpost cannot process LLVM IR 223cmd_ld_single = $(if $(objtool-enabled)$(is-single-obj-m), ; $(LD) $(ld_flags) -r -o $(tmp-target) $@; mv $(tmp-target) $@) 224endif 225 226quiet_cmd_cc_o_c = CC $(quiet_modtag) $@ 227 cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $< \ 228 $(cmd_ld_single) \ 229 $(cmd_objtool) 230 231define rule_cc_o_c 232 $(call cmd_and_fixdep,cc_o_c) 233 $(call cmd,checksrc) 234 $(call cmd,checkdoc) 235 $(call cmd,gen_objtooldep) 236 $(call cmd,gen_symversions_c) 237 $(call cmd,record_mcount) 238 $(call cmd,warn_shared_object) 239endef 240 241quiet_cmd_as_o_S = AS $(quiet_modtag) $@ 242 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $< $(cmd_objtool) 243 244define rule_as_o_S 245 $(call cmd_and_fixdep,as_o_S) 246 $(call cmd,gen_objtooldep) 247 $(call cmd,gen_symversions_S) 248 $(call cmd,warn_shared_object) 249endef 250 251# Copy a file 252# =========================================================================== 253# 'cp' preserves permissions. If you use it to copy a file in read-only srctree, 254# the copy would be read-only as well, leading to an error when executing the 255# rule next time. Use 'cat' instead in order to generate a writable file. 256quiet_cmd_copy = COPY $@ 257 cmd_copy = cat $< > $@ 258 259$(obj)/%: $(src)/%_shipped 260 $(call cmd,copy) 261 262# Commands useful for building a boot image 263# =========================================================================== 264# 265# Use as following: 266# 267# target: source(s) FORCE 268# $(if_changed,ld/objcopy/gzip) 269# 270# and add target to 'targets' so that we know we have to 271# read in the saved command line 272 273# Linking 274# --------------------------------------------------------------------------- 275 276quiet_cmd_ld = LD $@ 277 cmd_ld = $(LD) $(ld_flags) $(real-prereqs) -o $@ 278 279# Archive 280# --------------------------------------------------------------------------- 281 282quiet_cmd_ar = AR $@ 283 cmd_ar = rm -f $@; $(AR) cDPrsT $@ $(real-prereqs) 284 285# Objcopy 286# --------------------------------------------------------------------------- 287 288quiet_cmd_objcopy = OBJCOPY $@ 289cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@ 290 291# Gzip 292# --------------------------------------------------------------------------- 293 294quiet_cmd_gzip = GZIP $@ 295 cmd_gzip = cat $(real-prereqs) | $(KGZIP) -n -f -9 > $@ 296 297# Bzip2 298# --------------------------------------------------------------------------- 299 300# Bzip2 and LZMA do not include size in file... so we have to fake that; 301# append the size as a 32-bit littleendian number as gzip does. 302size_append = printf $(shell \ 303dec_size=0; \ 304for F in $(real-prereqs); do \ 305 fsize=$$($(CONFIG_SHELL) $(srctree)/scripts/file-size.sh $$F); \ 306 dec_size=$$(expr $$dec_size + $$fsize); \ 307done; \ 308printf "%08x\n" $$dec_size | \ 309 sed 's/\(..\)/\1 /g' | { \ 310 read ch0 ch1 ch2 ch3; \ 311 for ch in $$ch3 $$ch2 $$ch1 $$ch0; do \ 312 printf '%s%03o' '\\' $$((0x$$ch)); \ 313 done; \ 314 } \ 315) 316 317quiet_cmd_file_size = GEN $@ 318 cmd_file_size = $(size_append) > $@ 319 320quiet_cmd_bzip2 = BZIP2 $@ 321 cmd_bzip2 = cat $(real-prereqs) | $(KBZIP2) -9 > $@ 322 323quiet_cmd_bzip2_with_size = BZIP2 $@ 324 cmd_bzip2_with_size = { cat $(real-prereqs) | $(KBZIP2) -9; $(size_append); } > $@ 325 326# Lzma 327# --------------------------------------------------------------------------- 328 329quiet_cmd_lzma = LZMA $@ 330 cmd_lzma = cat $(real-prereqs) | $(LZMA) -9 > $@ 331 332quiet_cmd_lzma_with_size = LZMA $@ 333 cmd_lzma_with_size = { cat $(real-prereqs) | $(LZMA) -9; $(size_append); } > $@ 334 335quiet_cmd_lzo = LZO $@ 336 cmd_lzo = cat $(real-prereqs) | $(KLZOP) -9 > $@ 337 338quiet_cmd_lzo_with_size = LZO $@ 339 cmd_lzo_with_size = { cat $(real-prereqs) | $(KLZOP) -9; $(size_append); } > $@ 340 341quiet_cmd_lz4 = LZ4 $@ 342 cmd_lz4 = cat $(real-prereqs) | $(LZ4) -l -9 - - > $@ 343 344quiet_cmd_lz4_with_size = LZ4 $@ 345 cmd_lz4_with_size = { cat $(real-prereqs) | $(LZ4) -l -9 - -; \ 346 $(size_append); } > $@ 347 348# U-Boot mkimage 349# --------------------------------------------------------------------------- 350 351MKIMAGE := $(srctree)/scripts/mkuboot.sh 352 353# SRCARCH just happens to match slightly more than ARCH (on sparc), so reduces 354# the number of overrides in arch makefiles 355UIMAGE_ARCH ?= $(SRCARCH) 356UIMAGE_COMPRESSION ?= $(or $(2),none) 357UIMAGE_OPTS-y ?= 358UIMAGE_TYPE ?= kernel 359UIMAGE_LOADADDR ?= arch_must_set_this 360UIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR) 361UIMAGE_NAME ?= Linux-$(KERNELRELEASE) 362 363quiet_cmd_uimage = UIMAGE $@ 364 cmd_uimage = $(BASH) $(MKIMAGE) -A $(UIMAGE_ARCH) -O linux \ 365 -C $(UIMAGE_COMPRESSION) $(UIMAGE_OPTS-y) \ 366 -T $(UIMAGE_TYPE) \ 367 -a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \ 368 -n '$(UIMAGE_NAME)' -d $< $@ 369 370# Flat Image Tree (FIT) 371# This allows for packaging of a kernel and all devicetrees files, using 372# compression. 373# --------------------------------------------------------------------------- 374 375MAKE_FIT := $(srctree)/scripts/make_fit.py 376 377# Use this to override the compression algorithm 378FIT_COMPRESSION ?= gzip 379 380quiet_cmd_fit = FIT $@ 381 cmd_fit = $(MAKE_FIT) -o $@ --arch $(UIMAGE_ARCH) --os linux \ 382 --name '$(UIMAGE_NAME)' \ 383 $(if $(findstring 1,$(KBUILD_VERBOSE)),-v) \ 384 $(if $(FIT_DECOMPOSE_DTBS),--decompose-dtbs) \ 385 --compress $(FIT_COMPRESSION) -k $< @$(word 2,$^) 386 387# XZ 388# --------------------------------------------------------------------------- 389# Use xzkern or xzkern_with_size to compress the kernel image and xzmisc to 390# compress other things. 391# 392# xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage 393# of the kernel decompressor. A BCJ filter is used if it is available for 394# the target architecture. 395# 396# xzkern_with_size also appends uncompressed size of the data using 397# size_append. The .xz format has the size information available at the end 398# of the file too, but it's in more complex format and it's good to avoid 399# changing the part of the boot code that reads the uncompressed size. 400# Note that the bytes added by size_append will make the xz tool think that 401# the file is corrupt. This is expected. 402# 403# xzmisc doesn't use size_append, so it can be used to create normal .xz 404# files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very 405# big dictionary would increase the memory usage too much in the multi-call 406# decompression mode. A BCJ filter isn't used either. 407quiet_cmd_xzkern = XZKERN $@ 408 cmd_xzkern = cat $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh > $@ 409 410quiet_cmd_xzkern_with_size = XZKERN $@ 411 cmd_xzkern_with_size = { cat $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh; \ 412 $(size_append); } > $@ 413 414quiet_cmd_xzmisc = XZMISC $@ 415 cmd_xzmisc = cat $(real-prereqs) | $(XZ) --check=crc32 --lzma2=dict=1MiB > $@ 416 417# ZSTD 418# --------------------------------------------------------------------------- 419# Appends the uncompressed size of the data using size_append. The .zst 420# format has the size information available at the beginning of the file too, 421# but it's in a more complex format and it's good to avoid changing the part 422# of the boot code that reads the uncompressed size. 423# 424# Note that the bytes added by size_append will make the zstd tool think that 425# the file is corrupt. This is expected. 426# 427# zstd uses a maximum window size of 8 MB. zstd22 uses a maximum window size of 428# 128 MB. zstd22 is used for kernel compression because it is decompressed in a 429# single pass, so zstd doesn't need to allocate a window buffer. When streaming 430# decompression is used, like initramfs decompression, zstd22 should likely not 431# be used because it would require zstd to allocate a 128 MB buffer. 432 433quiet_cmd_zstd = ZSTD $@ 434 cmd_zstd = cat $(real-prereqs) | $(ZSTD) -19 > $@ 435 436quiet_cmd_zstd22 = ZSTD22 $@ 437 cmd_zstd22 = cat $(real-prereqs) | $(ZSTD) -22 --ultra > $@ 438 439quiet_cmd_zstd22_with_size = ZSTD22 $@ 440 cmd_zstd22_with_size = { cat $(real-prereqs) | $(ZSTD) -22 --ultra; $(size_append); } > $@ 441 442# ASM offsets 443# --------------------------------------------------------------------------- 444 445# Default sed regexp - multiline due to syntax constraints 446# 447# Use [:space:] because LLVM's integrated assembler inserts <tab> around 448# the .ascii directive whereas GCC keeps the <space> as-is. 449define sed-offsets 450 's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \ 451 /^->/{s:->#\(.*\):/* \1 */:; \ 452 s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \ 453 s:->::; p;}' 454endef 455 456# Use filechk to avoid rebuilds when a header changes, but the resulting file 457# does not 458define filechk_offsets 459 echo "#ifndef $2"; \ 460 echo "#define $2"; \ 461 echo "/*"; \ 462 echo " * DO NOT MODIFY."; \ 463 echo " *"; \ 464 echo " * This file was generated by Kbuild"; \ 465 echo " */"; \ 466 echo ""; \ 467 sed -ne $(sed-offsets) < $<; \ 468 echo ""; \ 469 echo "#endif" 470endef 471