scripts/Makefile.lib

   1 # SPDX-License-Identifier: GPL-2.0
   2 # Backward compatibility
   3 asflags-y  += $(EXTRA_AFLAGS)
   4 ccflags-y  += $(EXTRA_CFLAGS)
   5 cppflags-y += $(EXTRA_CPPFLAGS)
   6 ldflags-y  += $(EXTRA_LDFLAGS)
   7
   8 # flags that take effect in current and sub directories
   9 KBUILD_AFLAGS += $(subdir-asflags-y)
  10 KBUILD_CFLAGS += $(subdir-ccflags-y)
  11
  12 # Figure out what we need to build from the various variables
  13 # ===========================================================================
  14
  15 # When an object is listed to be built compiled-in and modular,
  16 # only build the compiled-in version
  17 obj-m := $(filter-out $(obj-y),$(obj-m))
  18
  19 # Libraries are always collected in one lib file.
  20 # Filter out objects already built-in
  21 lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m)))
  22
  23 # Subdirectories we need to descend into
  24 subdir-ym := $(sort $(subdir-y) $(subdir-m) \
  25                         $(patsubst %/,%, $(filter %/, $(obj-y) $(obj-m))))
  26
  27 # Handle objects in subdirs:
  28 # - If we encounter foo/ in $(obj-y), replace it by foo/built-in.a and
  29 #   foo/modules.order
  30 # - If we encounter foo/ in $(obj-m), replace it by foo/modules.order
  31 #
  32 # Generate modules.order to determine modorder. Unfortunately, we don't have
  33 # information about ordering between -y and -m subdirs. Just put -y's first.
  34
  35 ifdef need-modorder
  36 obj-m := $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m))
  37 else
  38 obj-m := $(filter-out %/, $(obj-m))
  39 endif
  40
  41 ifdef need-builtin
  42 obj-y           := $(patsubst %/, %/built-in.a, $(obj-y))
  43 else
  44 obj-y           := $(filter-out %/, $(obj-y))
  45 endif
  46
  47 # Expand $(foo-objs) $(foo-y) etc. by replacing their individuals
  48 suffix-search = $(strip $(foreach s, $3, $($(1:%$(strip $2)=%$s))))
  49 # List composite targets that are constructed by combining other targets
  50 multi-search = $(sort $(foreach m, $1, $(if $(call suffix-search, $m, $2, $3 -), $m)))
  51 # List primitive targets that are compiled from source files
  52 real-search = $(foreach m, $1, $(if $(call suffix-search, $m, $2, $3 -), $(call suffix-search, $m, $2, $3), $m))
  53
  54 # If $(foo-objs), $(foo-y), $(foo-m), or $(foo-) exists, foo.o is a composite object
  55 multi-obj-y := $(call multi-search, $(obj-y), .o, -objs -y)
  56 multi-obj-m := $(call multi-search, $(obj-m), .o, -objs -y -m)
  57 multi-obj-ym := $(multi-obj-y) $(multi-obj-m)
  58
  59 # Replace multi-part objects by their individual parts,
  60 # including built-in.a from subdirectories
  61 real-obj-y := $(call real-search, $(obj-y), .o, -objs -y)
  62 real-obj-m := $(call real-search, $(obj-m), .o, -objs -y -m)
  63
  64 always-y += $(always-m)
  65
  66 # hostprogs-always-y += foo
  67 # ... is a shorthand for
  68 # hostprogs += foo
  69 # always-y  += foo
  70 hostprogs += $(hostprogs-always-y) $(hostprogs-always-m)
  71 always-y += $(hostprogs-always-y) $(hostprogs-always-m)
  72
  73 # userprogs-always-y is likewise.
  74 userprogs += $(userprogs-always-y) $(userprogs-always-m)
  75 always-y += $(userprogs-always-y) $(userprogs-always-m)
  76
  77 # DTB
  78 # If CONFIG_OF_ALL_DTBS is enabled, all DT blobs are built
  79 dtb-$(CONFIG_OF_ALL_DTBS)       += $(dtb-)
  80
  81 # Composite DTB (i.e. DTB constructed by overlay)
  82 multi-dtb-y := $(call multi-search, $(dtb-y), .dtb, -dtbs)
  83 # Primitive DTB compiled from *.dts
  84 real-dtb-y := $(call real-search, $(dtb-y), .dtb, -dtbs)
  85 # Base DTB that overlay is applied onto (each first word of $(*-dtbs) expansion)
  86 base-dtb-y := $(foreach m, $(multi-dtb-y), $(firstword $(call suffix-search, $m, .dtb, -dtbs)))
  87
  88 always-y                        += $(dtb-y)
  89
  90 ifneq ($(CHECK_DTBS),)
  91 always-y += $(patsubst %.dtb,%.dt.yaml, $(real-dtb-y))
  92 always-y += $(patsubst %.dtbo,%.dt.yaml, $(real-dtb-y))
  93 endif
  94
  95 # Add subdir path
  96
  97 extra-y         := $(addprefix $(obj)/,$(extra-y))
  98 always-y        := $(addprefix $(obj)/,$(always-y))
  99 targets         := $(addprefix $(obj)/,$(targets))
 100 obj-m           := $(addprefix $(obj)/,$(obj-m))
 101 lib-y           := $(addprefix $(obj)/,$(lib-y))
 102 real-obj-y      := $(addprefix $(obj)/,$(real-obj-y))
 103 real-obj-m      := $(addprefix $(obj)/,$(real-obj-m))
 104 multi-obj-m     := $(addprefix $(obj)/, $(multi-obj-m))
 105 multi-dtb-y     := $(addprefix $(obj)/, $(multi-dtb-y))
 106 real-dtb-y      := $(addprefix $(obj)/, $(real-dtb-y))
 107 subdir-ym       := $(addprefix $(obj)/,$(subdir-ym))
 108
 109 # Finds the multi-part object the current object will be linked into.
 110 # If the object belongs to two or more multi-part objects, list them all.
 111 modname-multi = $(sort $(foreach m,$(multi-obj-ym),\
 112                 $(if $(filter $*.o, $(call suffix-search, $m, .o, -objs -y -m)),$(m:.o=))))
 113
 114 __modname = $(if $(modname-multi),$(modname-multi),$(basetarget))
 115
 116 modname = $(subst $(space),:,$(__modname))
 117 modfile = $(addprefix $(obj)/,$(__modname))
 118
 119 # target with $(obj)/ and its suffix stripped
 120 target-stem = $(basename $(patsubst $(obj)/%,%,$@))
 121
 122 # These flags are needed for modversions and compiling, so we define them here
 123 # $(modname_flags) defines KBUILD_MODNAME as the name of the module it will
 124 # end up in (or would, if it gets compiled in)
 125 name-fix-token = $(subst $(comma),_,$(subst -,_,$1))
 126 name-fix = $(call stringify,$(call name-fix-token,$1))
 127 basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget))
 128 modname_flags  = -DKBUILD_MODNAME=$(call name-fix,$(modname)) \
 129                  -D__KBUILD_MODNAME=kmod_$(call name-fix-token,$(modname))
 130 modfile_flags  = -DKBUILD_MODFILE=$(call stringify,$(modfile))
 131
 132 _c_flags       = $(filter-out $(CFLAGS_REMOVE_$(target-stem).o), \
 133                      $(filter-out $(ccflags-remove-y), \
 134                          $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(ccflags-y)) \
 135                      $(CFLAGS_$(target-stem).o))
 136 _a_flags       = $(filter-out $(AFLAGS_REMOVE_$(target-stem).o), \
 137                      $(filter-out $(asflags-remove-y), \
 138                          $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) $(asflags-y)) \
 139                      $(AFLAGS_$(target-stem).o))
 140 _cpp_flags     = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(target-stem).lds)
 141
 142 #
 143 # Enable gcov profiling flags for a file, directory or for all files depending
 144 # on variables GCOV_PROFILE_obj.o, GCOV_PROFILE and CONFIG_GCOV_PROFILE_ALL
 145 # (in this order)
 146 #
 147 ifeq ($(CONFIG_GCOV_KERNEL),y)
 148 _c_flags += $(if $(patsubst n%,, \
 149                 $(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \
 150                 $(CFLAGS_GCOV))
 151 endif
 152
 153 #
 154 # Enable address sanitizer flags for kernel except some files or directories
 155 # we don't want to check (depends on variables KASAN_SANITIZE_obj.o, KASAN_SANITIZE)
 156 #
 157 ifeq ($(CONFIG_KASAN),y)
 158 ifneq ($(CONFIG_KASAN_HW_TAGS),y)
 159 _c_flags += $(if $(patsubst n%,, \
 160                 $(KASAN_SANITIZE_$(basetarget).o)$(KASAN_SANITIZE)y), \
 161                 $(CFLAGS_KASAN), $(CFLAGS_KASAN_NOSANITIZE))
 162 endif
 163 endif
 164
 165 ifeq ($(CONFIG_UBSAN),y)
 166 _c_flags += $(if $(patsubst n%,, \
 167                 $(UBSAN_SANITIZE_$(basetarget).o)$(UBSAN_SANITIZE)$(CONFIG_UBSAN_SANITIZE_ALL)), \
 168                 $(CFLAGS_UBSAN))
 169 endif
 170
 171 ifeq ($(CONFIG_KCOV),y)
 172 _c_flags += $(if $(patsubst n%,, \
 173         $(KCOV_INSTRUMENT_$(basetarget).o)$(KCOV_INSTRUMENT)$(CONFIG_KCOV_INSTRUMENT_ALL)), \
 174         $(CFLAGS_KCOV))
 175 endif
 176
 177 #
 178 # Enable KCSAN flags except some files or directories we don't want to check
 179 # (depends on variables KCSAN_SANITIZE_obj.o, KCSAN_SANITIZE)
 180 #
 181 ifeq ($(CONFIG_KCSAN),y)
 182 _c_flags += $(if $(patsubst n%,, \
 183         $(KCSAN_SANITIZE_$(basetarget).o)$(KCSAN_SANITIZE)y), \
 184         $(CFLAGS_KCSAN))
 185 endif
 186
 187 # $(srctree)/$(src) for including checkin headers from generated source files
 188 # $(objtree)/$(obj) for including generated headers from checkin source files
 189 ifeq ($(KBUILD_EXTMOD),)
 190 ifdef building_out_of_srctree
 191 _c_flags   += -I $(srctree)/$(src) -I $(objtree)/$(obj)
 192 _a_flags   += -I $(srctree)/$(src) -I $(objtree)/$(obj)
 193 _cpp_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj)
 194 endif
 195 endif
 196
 197 part-of-module = $(if $(filter $(basename $@).o, $(real-obj-m)),y)
 198 quiet_modtag = $(if $(part-of-module),[M],   )
 199
 200 modkern_cflags =                                          \
 201         $(if $(part-of-module),                           \
 202                 $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
 203                 $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL) $(modfile_flags))
 204
 205 modkern_aflags = $(if $(part-of-module),                                \
 206                         $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE),       \
 207                         $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL))
 208
 209 c_flags        = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \
 210                  -include $(srctree)/include/linux/compiler_types.h       \
 211                  $(_c_flags) $(modkern_cflags)                           \
 212                  $(basename_flags) $(modname_flags)
 213
 214 a_flags        = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \
 215                  $(_a_flags) $(modkern_aflags)
 216
 217 cpp_flags      = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \
 218                  $(_cpp_flags)
 219
 220 ld_flags       = $(KBUILD_LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F))
 221
 222 DTC_INCLUDE    := $(srctree)/scripts/dtc/include-prefixes
 223
 224 dtc_cpp_flags  = -Wp,-MMD,$(depfile).pre.tmp -nostdinc                    \
 225                  $(addprefix -I,$(DTC_INCLUDE))                          \
 226                  -undef -D__DTS__
 227
 228 ifeq ($(CONFIG_LTO_CLANG),y)
 229 # With CONFIG_LTO_CLANG, .o files in modules might be LLVM bitcode, so we
 230 # need to run LTO to compile them into native code (.lto.o) before further
 231 # processing.
 232 mod-prelink-ext := .lto
 233 endif
 234
 235 # Objtool arguments are also needed for modfinal with LTO, so we define
 236 # then here to avoid duplication.
 237 objtool_args =                                                          \
 238         $(if $(CONFIG_UNWINDER_ORC),orc generate,check)                 \
 239         $(if $(part-of-module), --module,)                              \
 240         $(if $(CONFIG_FRAME_POINTER),, --no-fp)                         \
 241         $(if $(or $(CONFIG_GCOV_KERNEL),$(CONFIG_LTO_CLANG)),           \
 242                 --no-unreachable,)                                      \
 243         $(if $(CONFIG_RETPOLINE), --retpoline,)                         \
 244         $(if $(CONFIG_X86_SMAP), --uaccess,)                            \
 245         $(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount,)
 246
 247 # Useful for describing the dependency of composite objects
 248 # Usage:
 249 #   $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add)
 250 define multi_depend
 251 $(foreach m, $(notdir $1), \
 252         $(eval $(obj)/$m: \
 253         $(addprefix $(obj)/, $(foreach s, $3, $($(m:%$(strip $2)=%$(s)))))))
 254 endef
 255
 256 quiet_cmd_copy = COPY    $@
 257       cmd_copy = cp $< $@
 258
 259 # Shipped files
 260 # ===========================================================================
 261 # 'cp' preserves permissions. If you use it to copy a file in read-only srctree,
 262 # the copy would be read-only as well, leading to an error when executing the
 263 # rule next time. Use 'cat' instead in order to generate a writable file.
 264
 265 quiet_cmd_shipped = SHIPPED $@
 266 cmd_shipped = cat $< > $@
 267
 268 $(obj)/%: $(src)/%_shipped
 269         $(call cmd,shipped)
 270
 271 # Commands useful for building a boot image
 272 # ===========================================================================
 273 #
 274 #       Use as following:
 275 #
 276 #       target: source(s) FORCE
 277 #               $(if_changed,ld/objcopy/gzip)
 278 #
 279 #       and add target to 'targets' so that we know we have to
 280 #       read in the saved command line
 281
 282 # Linking
 283 # ---------------------------------------------------------------------------
 284
 285 quiet_cmd_ld = LD      $@
 286       cmd_ld = $(LD) $(ld_flags) $(real-prereqs) -o $@
 287
 288 # Archive
 289 # ---------------------------------------------------------------------------
 290
 291 quiet_cmd_ar = AR      $@
 292       cmd_ar = rm -f $@; $(AR) cDPrsT $@ $(real-prereqs)
 293
 294 # Objcopy
 295 # ---------------------------------------------------------------------------
 296
 297 quiet_cmd_objcopy = OBJCOPY $@
 298 cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@
 299
 300 # Gzip
 301 # ---------------------------------------------------------------------------
 302
 303 quiet_cmd_gzip = GZIP    $@
 304       cmd_gzip = cat $(real-prereqs) | $(KGZIP) -n -f -9 > $@
 305
 306 # DTC
 307 # ---------------------------------------------------------------------------
 308 DTC ?= $(objtree)/scripts/dtc/dtc
 309 DTC_FLAGS += -Wno-interrupt_provider
 310
 311 # Disable noisy checks by default
 312 ifeq ($(findstring 1,$(KBUILD_EXTRA_WARN)),)
 313 DTC_FLAGS += -Wno-unit_address_vs_reg \
 314         -Wno-unit_address_format \
 315         -Wno-avoid_unnecessary_addr_size \
 316         -Wno-alias_paths \
 317         -Wno-graph_child_address \
 318         -Wno-simple_bus_reg \
 319         -Wno-unique_unit_address \
 320         -Wno-pci_device_reg
 321 endif
 322
 323 ifneq ($(findstring 2,$(KBUILD_EXTRA_WARN)),)
 324 DTC_FLAGS += -Wnode_name_chars_strict \
 325         -Wproperty_name_chars_strict \
 326         -Winterrupt_provider
 327 endif
 328
 329 DTC_FLAGS += $(DTC_FLAGS_$(basetarget))
 330
 331 # Set -@ if the target is a base DTB that overlay is applied onto
 332 DTC_FLAGS += $(if $(filter $(patsubst $(obj)/%,%,$@), $(base-dtb-y)), -@)
 333
 334 # Generate an assembly file to wrap the output of the device tree compiler
 335 quiet_cmd_dt_S_dtb= DTB     $@
 336 cmd_dt_S_dtb=                                           \
 337 {                                                       \
 338         echo '\#include <asm-generic/vmlinux.lds.h>';   \
 339         echo '.section .dtb.init.rodata,"a"';           \
 340         echo '.balign STRUCT_ALIGNMENT';                \
 341         echo '.global __dtb_$(subst -,_,$(*F))_begin';  \
 342         echo '__dtb_$(subst -,_,$(*F))_begin:';         \
 343         echo '.incbin "$<" ';                           \
 344         echo '__dtb_$(subst -,_,$(*F))_end:';           \
 345         echo '.global __dtb_$(subst -,_,$(*F))_end';    \
 346         echo '.balign STRUCT_ALIGNMENT';                \
 347 } > $@
 348
 349 $(obj)/%.dtb.S: $(obj)/%.dtb FORCE
 350         $(call if_changed,dt_S_dtb)
 351
 352 quiet_cmd_dtc = DTC     $@
 353 cmd_dtc = $(HOSTCC) -E $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \
 354         $(DTC) -o $@ -b 0 \
 355                 $(addprefix -i,$(dir $<) $(DTC_INCLUDE)) $(DTC_FLAGS) \
 356                 -d $(depfile).dtc.tmp $(dtc-tmp) ; \
 357         cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile)
 358
 359 $(obj)/%.dtb: $(src)/%.dts $(DTC) FORCE
 360         $(call if_changed_dep,dtc)
 361
 362 $(obj)/%.dtbo: $(src)/%.dts $(DTC) FORCE
 363         $(call if_changed_dep,dtc)
 364
 365 quiet_cmd_fdtoverlay = DTOVL   $@
 366       cmd_fdtoverlay = $(objtree)/scripts/dtc/fdtoverlay -o $@ -i $(real-prereqs)
 367
 368 $(multi-dtb-y): FORCE
 369         $(call if_changed,fdtoverlay)
 370 $(call multi_depend, $(multi-dtb-y), .dtb, -dtbs)
 371
 372 DT_CHECKER ?= dt-validate
 373 DT_CHECKER_FLAGS ?= $(if $(DT_SCHEMA_FILES),,-m)
 374 DT_BINDING_DIR := Documentation/devicetree/bindings
 375 # DT_TMP_SCHEMA may be overridden from Documentation/devicetree/bindings/Makefile
 376 DT_TMP_SCHEMA ?= $(objtree)/$(DT_BINDING_DIR)/processed-schema.json
 377
 378 quiet_cmd_dtb_check =   CHECK   $@
 379       cmd_dtb_check =   $(DT_CHECKER) $(DT_CHECKER_FLAGS) -u $(srctree)/$(DT_BINDING_DIR) -p $(DT_TMP_SCHEMA) $@
 380
 381 define rule_dtc
 382         $(call cmd_and_fixdep,dtc)
 383         $(call cmd,dtb_check)
 384 endef
 385
 386 $(obj)/%.dt.yaml: $(src)/%.dts $(DTC) $(DT_TMP_SCHEMA) FORCE
 387         $(call if_changed_rule,dtc)
 388
 389 dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp)
 390
 391 # Bzip2
 392 # ---------------------------------------------------------------------------
 393
 394 # Bzip2 and LZMA do not include size in file... so we have to fake that;
 395 # append the size as a 32-bit littleendian number as gzip does.
 396 size_append = printf $(shell                                            \
 397 dec_size=0;                                                             \
 398 for F in $(real-prereqs); do                                    \
 399         fsize=$$($(CONFIG_SHELL) $(srctree)/scripts/file-size.sh $$F);  \
 400         dec_size=$$(expr $$dec_size + $$fsize);                         \
 401 done;                                                                   \
 402 printf "%08x\n" $$dec_size |                                            \
 403         sed 's/\(..\)/\1 /g' | {                                        \
 404                 read ch0 ch1 ch2 ch3;                                   \
 405                 for ch in $$ch3 $$ch2 $$ch1 $$ch0; do                   \
 406                         printf '%s%03o' '\\' $$((0x$$ch));              \
 407                 done;                                                   \
 408         }                                                               \
 409 )
 410
 411 quiet_cmd_bzip2 = BZIP2   $@
 412       cmd_bzip2 = { cat $(real-prereqs) | $(KBZIP2) -9; $(size_append); } > $@
 413
 414 # Lzma
 415 # ---------------------------------------------------------------------------
 416
 417 quiet_cmd_lzma = LZMA    $@
 418       cmd_lzma = { cat $(real-prereqs) | $(LZMA) -9; $(size_append); } > $@
 419
 420 quiet_cmd_lzo = LZO     $@
 421       cmd_lzo = { cat $(real-prereqs) | $(KLZOP) -9; $(size_append); } > $@
 422
 423 quiet_cmd_lz4 = LZ4     $@
 424       cmd_lz4 = { cat $(real-prereqs) | $(LZ4) -l -c1 stdin stdout; \
 425                   $(size_append); } > $@
 426
 427 # U-Boot mkimage
 428 # ---------------------------------------------------------------------------
 429
 430 MKIMAGE := $(srctree)/scripts/mkuboot.sh
 431
 432 # SRCARCH just happens to match slightly more than ARCH (on sparc), so reduces
 433 # the number of overrides in arch makefiles
 434 UIMAGE_ARCH ?= $(SRCARCH)
 435 UIMAGE_COMPRESSION ?= $(if $(2),$(2),none)
 436 UIMAGE_OPTS-y ?=
 437 UIMAGE_TYPE ?= kernel
 438 UIMAGE_LOADADDR ?= arch_must_set_this
 439 UIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR)
 440 UIMAGE_NAME ?= 'Linux-$(KERNELRELEASE)'
 441
 442 quiet_cmd_uimage = UIMAGE  $@
 443       cmd_uimage = $(BASH) $(MKIMAGE) -A $(UIMAGE_ARCH) -O linux \
 444                         -C $(UIMAGE_COMPRESSION) $(UIMAGE_OPTS-y) \
 445                         -T $(UIMAGE_TYPE) \
 446                         -a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \
 447                         -n $(UIMAGE_NAME) -d $< $@
 448
 449 # XZ
 450 # ---------------------------------------------------------------------------
 451 # Use xzkern to compress the kernel image and xzmisc to compress other things.
 452 #
 453 # xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage
 454 # of the kernel decompressor. A BCJ filter is used if it is available for
 455 # the target architecture. xzkern also appends uncompressed size of the data
 456 # using size_append. The .xz format has the size information available at
 457 # the end of the file too, but it's in more complex format and it's good to
 458 # avoid changing the part of the boot code that reads the uncompressed size.
 459 # Note that the bytes added by size_append will make the xz tool think that
 460 # the file is corrupt. This is expected.
 461 #
 462 # xzmisc doesn't use size_append, so it can be used to create normal .xz
 463 # files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very
 464 # big dictionary would increase the memory usage too much in the multi-call
 465 # decompression mode. A BCJ filter isn't used either.
 466 quiet_cmd_xzkern = XZKERN  $@
 467       cmd_xzkern = { cat $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh; \
 468                      $(size_append); } > $@
 469
 470 quiet_cmd_xzmisc = XZMISC  $@
 471       cmd_xzmisc = cat $(real-prereqs) | $(XZ) --check=crc32 --lzma2=dict=1MiB > $@
 472
 473 # ZSTD
 474 # ---------------------------------------------------------------------------
 475 # Appends the uncompressed size of the data using size_append. The .zst
 476 # format has the size information available at the beginning of the file too,
 477 # but it's in a more complex format and it's good to avoid changing the part
 478 # of the boot code that reads the uncompressed size.
 479 #
 480 # Note that the bytes added by size_append will make the zstd tool think that
 481 # the file is corrupt. This is expected.
 482 #
 483 # zstd uses a maximum window size of 8 MB. zstd22 uses a maximum window size of
 484 # 128 MB. zstd22 is used for kernel compression because it is decompressed in a
 485 # single pass, so zstd doesn't need to allocate a window buffer. When streaming
 486 # decompression is used, like initramfs decompression, zstd22 should likely not
 487 # be used because it would require zstd to allocate a 128 MB buffer.
 488
 489 quiet_cmd_zstd = ZSTD    $@
 490       cmd_zstd = { cat $(real-prereqs) | $(ZSTD) -19; $(size_append); } > $@
 491
 492 quiet_cmd_zstd22 = ZSTD22  $@
 493       cmd_zstd22 = { cat $(real-prereqs) | $(ZSTD) -22 --ultra; $(size_append); } > $@
 494
 495 # ASM offsets
 496 # ---------------------------------------------------------------------------
 497
 498 # Default sed regexp - multiline due to syntax constraints
 499 #
 500 # Use [:space:] because LLVM's integrated assembler inserts <tab> around
 501 # the .ascii directive whereas GCC keeps the <space> as-is.
 502 define sed-offsets
 503         's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \
 504         /^->/{s:->#\(.*\):/* \1 */:; \
 505         s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
 506         s:->::; p;}'
 507 endef
 508
 509 # Use filechk to avoid rebuilds when a header changes, but the resulting file
 510 # does not
 511 define filechk_offsets
 512          echo "#ifndef $2"; \
 513          echo "#define $2"; \
 514          echo "/*"; \
 515          echo " * DO NOT MODIFY."; \
 516          echo " *"; \
 517          echo " * This file was generated by Kbuild"; \
 518          echo " */"; \
 519          echo ""; \
 520          sed -ne $(sed-offsets) < $<; \
 521          echo ""; \
 522          echo "#endif"
 523 endef