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1# Backward compatibility
2asflags-y += $(EXTRA_AFLAGS)
3ccflags-y += $(EXTRA_CFLAGS)
4cppflags-y += $(EXTRA_CPPFLAGS)
5ldflags-y += $(EXTRA_LDFLAGS)
6
7#
8# flags that take effect in sub directories
9export KBUILD_SUBDIR_ASFLAGS := $(KBUILD_SUBDIR_ASFLAGS) $(subdir-asflags-y)
10export KBUILD_SUBDIR_CCFLAGS := $(KBUILD_SUBDIR_CCFLAGS) $(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
18obj-m := $(filter-out $(obj-y),$(obj-m))
19
20# Libraries are always collected in one lib file.
21# Filter out objects already built-in
22
23lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m)))
24
25
26# Handle objects in subdirs
27# ---------------------------------------------------------------------------
28# o if we encounter foo in $(obj-y), replace it by foo/built-in.o
29# and add the directory to the list of dirs to descend into: $(subdir-y)
30# o if we encounter foo/ in $(obj-m), remove it from $(obj-m)
31# and add the directory to the list of dirs to descend into: $(subdir-m)
32
33# Determine modorder.
34# Unfortunately, we don't have information about ordering between -y
35# and -m subdirs. Just put -y's first.
36modorder := $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m:.o=.ko))
37
38__subdir-y := $(patsubst %/,%,$(filter %/, $(obj-y)))
39subdir-y += $(__subdir-y)
40__subdir-m := $(patsubst %/,%,$(filter %/, $(obj-m)))
41subdir-m += $(__subdir-m)
42obj-y := $(patsubst %/, %/built-in.o, $(obj-y))
43obj-m := $(filter-out %/, $(obj-m))
44
45# Subdirectories we need to descend into
46
47subdir-ym := $(sort $(subdir-y) $(subdir-m))
48
49# if $(foo-objs) exists, foo.o is a composite object
50multi-used-y := $(sort $(foreach m,$(obj-y), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))), $(m))))
51multi-used-m := $(sort $(foreach m,$(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))), $(m))))
52multi-used := $(multi-used-y) $(multi-used-m)
53single-used-m := $(sort $(filter-out $(multi-used-m),$(obj-m)))
54
55# Build list of the parts of our composite objects, our composite
56# objects depend on those (obviously)
57multi-objs-y := $(foreach m, $(multi-used-y), $($(m:.o=-objs)) $($(m:.o=-y)))
58multi-objs-m := $(foreach m, $(multi-used-m), $($(m:.o=-objs)) $($(m:.o=-y)))
59multi-objs := $(multi-objs-y) $(multi-objs-m)
60
61# $(subdir-obj-y) is the list of objects in $(obj-y) which uses dir/ to
62# tell kbuild to descend
63subdir-obj-y := $(filter %/built-in.o, $(obj-y))
64
65# $(obj-dirs) is a list of directories that contain object files
66obj-dirs := $(dir $(multi-objs) $(obj-y))
67
68# Replace multi-part objects by their individual parts, look at local dir only
69real-objs-y := $(foreach m, $(filter-out $(subdir-obj-y), $(obj-y)), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m))) $(extra-y)
70real-objs-m := $(foreach m, $(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))),$($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m)),$(m)))
71
72# Add subdir path
73
74extra-y := $(addprefix $(obj)/,$(extra-y))
75always := $(addprefix $(obj)/,$(always))
76targets := $(addprefix $(obj)/,$(targets))
77modorder := $(addprefix $(obj)/,$(modorder))
78obj-y := $(addprefix $(obj)/,$(obj-y))
79obj-m := $(addprefix $(obj)/,$(obj-m))
80lib-y := $(addprefix $(obj)/,$(lib-y))
81subdir-obj-y := $(addprefix $(obj)/,$(subdir-obj-y))
82real-objs-y := $(addprefix $(obj)/,$(real-objs-y))
83real-objs-m := $(addprefix $(obj)/,$(real-objs-m))
84single-used-m := $(addprefix $(obj)/,$(single-used-m))
85multi-used-y := $(addprefix $(obj)/,$(multi-used-y))
86multi-used-m := $(addprefix $(obj)/,$(multi-used-m))
87multi-objs-y := $(addprefix $(obj)/,$(multi-objs-y))
88multi-objs-m := $(addprefix $(obj)/,$(multi-objs-m))
89subdir-ym := $(addprefix $(obj)/,$(subdir-ym))
90obj-dirs := $(addprefix $(obj)/,$(obj-dirs))
91
92# These flags are needed for modversions and compiling, so we define them here
93# already
94# $(modname_flags) #defines KBUILD_MODNAME as the name of the module it will
95# end up in (or would, if it gets compiled in)
96# Note: Files that end up in two or more modules are compiled without the
97# KBUILD_MODNAME definition. The reason is that any made-up name would
98# differ in different configs.
99name-fix = $(squote)$(quote)$(subst $(comma),_,$(subst -,_,$1))$(quote)$(squote)
100basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget))
101modname_flags = $(if $(filter 1,$(words $(modname))),\
102 -DKBUILD_MODNAME=$(call name-fix,$(modname)))
103
104orig_c_flags = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(KBUILD_SUBDIR_CCFLAGS) \
105 $(ccflags-y) $(CFLAGS_$(basetarget).o)
106_c_flags = $(filter-out $(CFLAGS_REMOVE_$(basetarget).o), $(orig_c_flags))
107orig_a_flags = $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) $(KBUILD_SUBDIR_ASFLAGS) \
108 $(asflags-y) $(AFLAGS_$(basetarget).o)
109_a_flags = $(filter-out $(AFLAGS_REMOVE_$(basetarget).o), $(orig_a_flags))
110_cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(@F))
111
112#
113# Enable gcov profiling flags for a file, directory or for all files depending
114# on variables GCOV_PROFILE_obj.o, GCOV_PROFILE and CONFIG_GCOV_PROFILE_ALL
115# (in this order)
116#
117ifeq ($(CONFIG_GCOV_KERNEL),y)
118_c_flags += $(if $(patsubst n%,, \
119 $(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \
120 $(CFLAGS_GCOV))
121endif
122
123#
124# Enable address sanitizer flags for kernel except some files or directories
125# we don't want to check (depends on variables KASAN_SANITIZE_obj.o, KASAN_SANITIZE)
126#
127ifeq ($(CONFIG_KASAN),y)
128_c_flags += $(if $(patsubst n%,, \
129 $(KASAN_SANITIZE_$(basetarget).o)$(KASAN_SANITIZE)y), \
130 $(CFLAGS_KASAN))
131endif
132
133ifeq ($(CONFIG_UBSAN),y)
134_c_flags += $(if $(patsubst n%,, \
135 $(UBSAN_SANITIZE_$(basetarget).o)$(UBSAN_SANITIZE)$(CONFIG_UBSAN_SANITIZE_ALL)), \
136 $(CFLAGS_UBSAN))
137endif
138
139ifeq ($(CONFIG_KCOV),y)
140_c_flags += $(if $(patsubst n%,, \
141 $(KCOV_INSTRUMENT_$(basetarget).o)$(KCOV_INSTRUMENT)$(CONFIG_KCOV_INSTRUMENT_ALL)), \
142 $(CFLAGS_KCOV))
143endif
144
145# If building the kernel in a separate objtree expand all occurrences
146# of -Idir to -I$(srctree)/dir except for absolute paths (starting with '/').
147
148ifeq ($(KBUILD_SRC),)
149__c_flags = $(_c_flags)
150__a_flags = $(_a_flags)
151__cpp_flags = $(_cpp_flags)
152else
153
154# -I$(obj) locates generated .h files
155# $(call addtree,-I$(obj)) locates .h files in srctree, from generated .c files
156# and locates generated .h files
157# FIXME: Replace both with specific CFLAGS* statements in the makefiles
158__c_flags = $(if $(obj),-I$(srctree)/$(src) -I$(obj)) \
159 $(call flags,_c_flags)
160__a_flags = $(call flags,_a_flags)
161__cpp_flags = $(call flags,_cpp_flags)
162endif
163
164c_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
165 $(__c_flags) $(modkern_cflags) \
166 $(basename_flags) $(modname_flags)
167
168a_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
169 $(__a_flags) $(modkern_aflags)
170
171cpp_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
172 $(__cpp_flags)
173
174ld_flags = $(LDFLAGS) $(ldflags-y)
175
176dtc_cpp_flags = -Wp,-MD,$(depfile).pre.tmp -nostdinc \
177 -I$(srctree)/arch/$(SRCARCH)/boot/dts \
178 -I$(srctree)/arch/$(SRCARCH)/boot/dts/include \
179 -I$(srctree)/drivers/of/testcase-data \
180 -undef -D__DTS__
181
182# Finds the multi-part object the current object will be linked into
183modname-multi = $(sort $(foreach m,$(multi-used),\
184 $(if $(filter $(subst $(obj)/,,$*.o), $($(m:.o=-objs)) $($(m:.o=-y))),$(m:.o=))))
185
186# Useful for describing the dependency of composite objects
187# Usage:
188# $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add)
189define multi_depend
190$(foreach m, $(notdir $1), \
191 $(eval $(obj)/$m: \
192 $(addprefix $(obj)/, $(foreach s, $3, $($(m:%$(strip $2)=%$(s)))))))
193endef
194
195ifdef REGENERATE_PARSERS
196
197# GPERF
198# ---------------------------------------------------------------------------
199quiet_cmd_gperf = GPERF $@
200 cmd_gperf = gperf -t --output-file $@ -a -C -E -g -k 1,3,$$ -p -t $<
201
202.PRECIOUS: $(src)/%.hash.c_shipped
203$(src)/%.hash.c_shipped: $(src)/%.gperf
204 $(call cmd,gperf)
205
206# LEX
207# ---------------------------------------------------------------------------
208LEX_PREFIX = $(if $(LEX_PREFIX_${baseprereq}),$(LEX_PREFIX_${baseprereq}),yy)
209
210quiet_cmd_flex = LEX $@
211 cmd_flex = flex -o$@ -L -P $(LEX_PREFIX) $<
212
213.PRECIOUS: $(src)/%.lex.c_shipped
214$(src)/%.lex.c_shipped: $(src)/%.l
215 $(call cmd,flex)
216
217# YACC
218# ---------------------------------------------------------------------------
219YACC_PREFIX = $(if $(YACC_PREFIX_${baseprereq}),$(YACC_PREFIX_${baseprereq}),yy)
220
221quiet_cmd_bison = YACC $@
222 cmd_bison = bison -o$@ -t -l -p $(YACC_PREFIX) $<
223
224.PRECIOUS: $(src)/%.tab.c_shipped
225$(src)/%.tab.c_shipped: $(src)/%.y
226 $(call cmd,bison)
227
228quiet_cmd_bison_h = YACC $@
229 cmd_bison_h = bison -o/dev/null --defines=$@ -t -l -p $(YACC_PREFIX) $<
230
231.PRECIOUS: $(src)/%.tab.h_shipped
232$(src)/%.tab.h_shipped: $(src)/%.y
233 $(call cmd,bison_h)
234
235endif
236
237# Shipped files
238# ===========================================================================
239
240quiet_cmd_shipped = SHIPPED $@
241cmd_shipped = cat $< > $@
242
243$(obj)/%: $(src)/%_shipped
244 $(call cmd,shipped)
245
246# Commands useful for building a boot image
247# ===========================================================================
248#
249# Use as following:
250#
251# target: source(s) FORCE
252# $(if_changed,ld/objcopy/gzip)
253#
254# and add target to extra-y so that we know we have to
255# read in the saved command line
256
257# Linking
258# ---------------------------------------------------------------------------
259
260quiet_cmd_ld = LD $@
261cmd_ld = $(LD) $(LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F)) \
262 $(filter-out FORCE,$^) -o $@
263
264# Objcopy
265# ---------------------------------------------------------------------------
266
267quiet_cmd_objcopy = OBJCOPY $@
268cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@
269
270# Gzip
271# ---------------------------------------------------------------------------
272
273quiet_cmd_gzip = GZIP $@
274cmd_gzip = (cat $(filter-out FORCE,$^) | gzip -n -f -9 > $@) || \
275 (rm -f $@ ; false)
276
277# DTC
278# ---------------------------------------------------------------------------
279DTC ?= $(objtree)/scripts/dtc/dtc
280
281# Disable noisy checks by default
282ifeq ($(KBUILD_ENABLE_EXTRA_GCC_CHECKS),)
283DTC_FLAGS += -Wno-unit_address_vs_reg
284endif
285
286# Generate an assembly file to wrap the output of the device tree compiler
287quiet_cmd_dt_S_dtb= DTB $@
288cmd_dt_S_dtb= \
289( \
290 echo '\#include <asm-generic/vmlinux.lds.h>'; \
291 echo '.section .dtb.init.rodata,"a"'; \
292 echo '.balign STRUCT_ALIGNMENT'; \
293 echo '.global __dtb_$(*F)_begin'; \
294 echo '__dtb_$(*F)_begin:'; \
295 echo '.incbin "$<" '; \
296 echo '__dtb_$(*F)_end:'; \
297 echo '.global __dtb_$(*F)_end'; \
298 echo '.balign STRUCT_ALIGNMENT'; \
299) > $@
300
301$(obj)/%.dtb.S: $(obj)/%.dtb
302 $(call cmd,dt_S_dtb)
303
304quiet_cmd_dtc = DTC $@
305cmd_dtc = mkdir -p $(dir ${dtc-tmp}) ; \
306 $(CPP) $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \
307 $(DTC) -O dtb -o $@ -b 0 \
308 -i $(dir $<) $(DTC_FLAGS) \
309 -d $(depfile).dtc.tmp $(dtc-tmp) ; \
310 cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile)
311
312$(obj)/%.dtb: $(src)/%.dts FORCE
313 $(call if_changed_dep,dtc)
314
315dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp)
316
317# Bzip2
318# ---------------------------------------------------------------------------
319
320# Bzip2 and LZMA do not include size in file... so we have to fake that;
321# append the size as a 32-bit littleendian number as gzip does.
322size_append = printf $(shell \
323dec_size=0; \
324for F in $1; do \
325 fsize=$$(stat -c "%s" $$F); \
326 dec_size=$$(expr $$dec_size + $$fsize); \
327done; \
328printf "%08x\n" $$dec_size | \
329 sed 's/\(..\)/\1 /g' | { \
330 read ch0 ch1 ch2 ch3; \
331 for ch in $$ch3 $$ch2 $$ch1 $$ch0; do \
332 printf '%s%03o' '\\' $$((0x$$ch)); \
333 done; \
334 } \
335)
336
337quiet_cmd_bzip2 = BZIP2 $@
338cmd_bzip2 = (cat $(filter-out FORCE,$^) | \
339 bzip2 -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \
340 (rm -f $@ ; false)
341
342# Lzma
343# ---------------------------------------------------------------------------
344
345quiet_cmd_lzma = LZMA $@
346cmd_lzma = (cat $(filter-out FORCE,$^) | \
347 lzma -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \
348 (rm -f $@ ; false)
349
350quiet_cmd_lzo = LZO $@
351cmd_lzo = (cat $(filter-out FORCE,$^) | \
352 lzop -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \
353 (rm -f $@ ; false)
354
355quiet_cmd_lz4 = LZ4 $@
356cmd_lz4 = (cat $(filter-out FORCE,$^) | \
357 lz4c -l -c1 stdin stdout && $(call size_append, $(filter-out FORCE,$^))) > $@ || \
358 (rm -f $@ ; false)
359
360# U-Boot mkimage
361# ---------------------------------------------------------------------------
362
363MKIMAGE := $(srctree)/scripts/mkuboot.sh
364
365# SRCARCH just happens to match slightly more than ARCH (on sparc), so reduces
366# the number of overrides in arch makefiles
367UIMAGE_ARCH ?= $(SRCARCH)
368UIMAGE_COMPRESSION ?= $(if $(2),$(2),none)
369UIMAGE_OPTS-y ?=
370UIMAGE_TYPE ?= kernel
371UIMAGE_LOADADDR ?= arch_must_set_this
372UIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR)
373UIMAGE_NAME ?= 'Linux-$(KERNELRELEASE)'
374UIMAGE_IN ?= $<
375UIMAGE_OUT ?= $@
376
377quiet_cmd_uimage = UIMAGE $(UIMAGE_OUT)
378 cmd_uimage = $(CONFIG_SHELL) $(MKIMAGE) -A $(UIMAGE_ARCH) -O linux \
379 -C $(UIMAGE_COMPRESSION) $(UIMAGE_OPTS-y) \
380 -T $(UIMAGE_TYPE) \
381 -a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \
382 -n $(UIMAGE_NAME) -d $(UIMAGE_IN) $(UIMAGE_OUT)
383
384# XZ
385# ---------------------------------------------------------------------------
386# Use xzkern to compress the kernel image and xzmisc to compress other things.
387#
388# xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage
389# of the kernel decompressor. A BCJ filter is used if it is available for
390# the target architecture. xzkern also appends uncompressed size of the data
391# using size_append. The .xz format has the size information available at
392# the end of the file too, but it's in more complex format and it's good to
393# avoid changing the part of the boot code that reads the uncompressed size.
394# Note that the bytes added by size_append will make the xz tool think that
395# the file is corrupt. This is expected.
396#
397# xzmisc doesn't use size_append, so it can be used to create normal .xz
398# files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very
399# big dictionary would increase the memory usage too much in the multi-call
400# decompression mode. A BCJ filter isn't used either.
401quiet_cmd_xzkern = XZKERN $@
402cmd_xzkern = (cat $(filter-out FORCE,$^) | \
403 sh $(srctree)/scripts/xz_wrap.sh && \
404 $(call size_append, $(filter-out FORCE,$^))) > $@ || \
405 (rm -f $@ ; false)
406
407quiet_cmd_xzmisc = XZMISC $@
408cmd_xzmisc = (cat $(filter-out FORCE,$^) | \
409 xz --check=crc32 --lzma2=dict=1MiB) > $@ || \
410 (rm -f $@ ; false)
1# SPDX-License-Identifier: GPL-2.0
2# Backward compatibility
3asflags-y += $(EXTRA_AFLAGS)
4ccflags-y += $(EXTRA_CFLAGS)
5cppflags-y += $(EXTRA_CPPFLAGS)
6ldflags-y += $(EXTRA_LDFLAGS)
7
8# flags that take effect in current and sub directories
9KBUILD_AFLAGS += $(subdir-asflags-y)
10KBUILD_CFLAGS += $(subdir-ccflags-y)
11KBUILD_RUSTFLAGS += $(subdir-rustflags-y)
12
13# Figure out what we need to build from the various variables
14# ===========================================================================
15
16# When an object is listed to be built compiled-in and modular,
17# only build the compiled-in version
18obj-m := $(filter-out $(obj-y),$(obj-m))
19
20# Libraries are always collected in one lib file.
21# Filter out objects already built-in
22lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m)))
23
24# Subdirectories we need to descend into
25subdir-ym := $(sort $(subdir-y) $(subdir-m) \
26 $(patsubst %/,%, $(filter %/, $(obj-y) $(obj-m))))
27
28# Handle objects in subdirs:
29# - If we encounter foo in $(obj-y), replace it by foo/built-in.a and
30# foo/modules.order
31# - If we encounter foo/ in $(obj-m), replace it by foo/modules.order
32#
33# Generate modules.order to determine modorder. Unfortunately, we don't have
34# information about ordering between -y and -m subdirs. Just put -y's first.
35
36ifdef need-modorder
37obj-m := $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m))
38else
39obj-m := $(filter-out %/, $(obj-m))
40endif
41
42ifdef need-builtin
43obj-y := $(patsubst %/, %/built-in.a, $(obj-y))
44else
45obj-y := $(filter-out %/, $(obj-y))
46endif
47
48# Expand $(foo-objs) $(foo-y) etc. by replacing their individuals
49suffix-search = $(strip $(foreach s, $3, $($(1:%$(strip $2)=%$s))))
50# List composite targets that are constructed by combining other targets
51multi-search = $(sort $(foreach m, $1, $(if $(call suffix-search, $m, $2, $3 -), $m)))
52# List primitive targets that are compiled from source files
53real-search = $(foreach m, $1, $(if $(call suffix-search, $m, $2, $3 -), $(call suffix-search, $m, $2, $3), $m))
54
55# If $(foo-objs), $(foo-y), $(foo-m), or $(foo-) exists, foo.o is a composite object
56multi-obj-y := $(call multi-search, $(obj-y), .o, -objs -y)
57multi-obj-m := $(call multi-search, $(obj-m), .o, -objs -y -m)
58multi-obj-ym := $(multi-obj-y) $(multi-obj-m)
59
60# Replace multi-part objects by their individual parts,
61# including built-in.a from subdirectories
62real-obj-y := $(call real-search, $(obj-y), .o, -objs -y)
63real-obj-m := $(call real-search, $(obj-m), .o, -objs -y -m)
64
65always-y += $(always-m)
66
67# hostprogs-always-y += foo
68# ... is a shorthand for
69# hostprogs += foo
70# always-y += foo
71hostprogs += $(hostprogs-always-y) $(hostprogs-always-m)
72always-y += $(hostprogs-always-y) $(hostprogs-always-m)
73
74# userprogs-always-y is likewise.
75userprogs += $(userprogs-always-y) $(userprogs-always-m)
76always-y += $(userprogs-always-y) $(userprogs-always-m)
77
78# Add subdir path
79
80ifneq ($(obj),.)
81extra-y := $(addprefix $(obj)/,$(extra-y))
82always-y := $(addprefix $(obj)/,$(always-y))
83targets := $(addprefix $(obj)/,$(targets))
84obj-m := $(addprefix $(obj)/,$(obj-m))
85lib-y := $(addprefix $(obj)/,$(lib-y))
86real-obj-y := $(addprefix $(obj)/,$(real-obj-y))
87real-obj-m := $(addprefix $(obj)/,$(real-obj-m))
88multi-obj-m := $(addprefix $(obj)/, $(multi-obj-m))
89subdir-ym := $(addprefix $(obj)/,$(subdir-ym))
90endif
91
92# Finds the multi-part object the current object will be linked into.
93# If the object belongs to two or more multi-part objects, list them all.
94modname-multi = $(sort $(foreach m,$(multi-obj-ym),\
95 $(if $(filter $*.o, $(call suffix-search, $m, .o, -objs -y -m)),$(m:.o=))))
96
97__modname = $(or $(modname-multi),$(basetarget))
98
99modname = $(subst $(space),:,$(__modname))
100modfile = $(addprefix $(obj)/,$(__modname))
101
102# target with $(obj)/ and its suffix stripped
103target-stem = $(basename $(patsubst $(obj)/%,%,$@))
104
105# These flags are needed for modversions and compiling, so we define them here
106# $(modname_flags) defines KBUILD_MODNAME as the name of the module it will
107# end up in (or would, if it gets compiled in)
108name-fix-token = $(subst $(comma),_,$(subst -,_,$1))
109name-fix = $(call stringify,$(call name-fix-token,$1))
110basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget))
111modname_flags = -DKBUILD_MODNAME=$(call name-fix,$(modname)) \
112 -D__KBUILD_MODNAME=kmod_$(call name-fix-token,$(modname))
113modfile_flags = -DKBUILD_MODFILE=$(call stringify,$(modfile))
114
115_c_flags = $(filter-out $(CFLAGS_REMOVE_$(target-stem).o), \
116 $(filter-out $(ccflags-remove-y), \
117 $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(ccflags-y)) \
118 $(CFLAGS_$(target-stem).o))
119_rust_flags = $(filter-out $(RUSTFLAGS_REMOVE_$(target-stem).o), \
120 $(filter-out $(rustflags-remove-y), \
121 $(KBUILD_RUSTFLAGS) $(rustflags-y)) \
122 $(RUSTFLAGS_$(target-stem).o))
123_a_flags = $(filter-out $(AFLAGS_REMOVE_$(target-stem).o), \
124 $(filter-out $(asflags-remove-y), \
125 $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) $(asflags-y)) \
126 $(AFLAGS_$(target-stem).o))
127_cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(target-stem).lds)
128
129#
130# Enable gcov profiling flags for a file, directory or for all files depending
131# on variables GCOV_PROFILE_obj.o, GCOV_PROFILE and CONFIG_GCOV_PROFILE_ALL
132# (in this order)
133#
134ifeq ($(CONFIG_GCOV_KERNEL),y)
135_c_flags += $(if $(patsubst n%,, \
136 $(GCOV_PROFILE_$(target-stem).o)$(GCOV_PROFILE)$(if $(is-kernel-object),$(CONFIG_GCOV_PROFILE_ALL))), \
137 $(CFLAGS_GCOV))
138endif
139
140#
141# Enable address sanitizer flags for kernel except some files or directories
142# we don't want to check (depends on variables KASAN_SANITIZE_obj.o, KASAN_SANITIZE)
143#
144ifeq ($(CONFIG_KASAN),y)
145ifneq ($(CONFIG_KASAN_HW_TAGS),y)
146_c_flags += $(if $(patsubst n%,, \
147 $(KASAN_SANITIZE_$(target-stem).o)$(KASAN_SANITIZE)$(is-kernel-object)), \
148 $(CFLAGS_KASAN), $(CFLAGS_KASAN_NOSANITIZE))
149_rust_flags += $(if $(patsubst n%,, \
150 $(KASAN_SANITIZE_$(target-stem).o)$(KASAN_SANITIZE)$(is-kernel-object)), \
151 $(RUSTFLAGS_KASAN))
152endif
153endif
154
155ifeq ($(CONFIG_KMSAN),y)
156_c_flags += $(if $(patsubst n%,, \
157 $(KMSAN_SANITIZE_$(target-stem).o)$(KMSAN_SANITIZE)$(is-kernel-object)), \
158 $(CFLAGS_KMSAN))
159_c_flags += $(if $(patsubst n%,, \
160 $(KMSAN_ENABLE_CHECKS_$(target-stem).o)$(KMSAN_ENABLE_CHECKS)$(is-kernel-object)), \
161 , -mllvm -msan-disable-checks=1)
162endif
163
164ifeq ($(CONFIG_UBSAN),y)
165_c_flags += $(if $(patsubst n%,, \
166 $(UBSAN_SANITIZE_$(target-stem).o)$(UBSAN_SANITIZE)$(is-kernel-object)), \
167 $(CFLAGS_UBSAN))
168_c_flags += $(if $(patsubst n%,, \
169 $(UBSAN_SIGNED_WRAP_$(target-stem).o)$(UBSAN_SANITIZE_$(target-stem).o)$(UBSAN_SIGNED_WRAP)$(UBSAN_SANITIZE)$(is-kernel-object)), \
170 $(CFLAGS_UBSAN_SIGNED_WRAP))
171endif
172
173ifeq ($(CONFIG_KCOV),y)
174_c_flags += $(if $(patsubst n%,, \
175 $(KCOV_INSTRUMENT_$(target-stem).o)$(KCOV_INSTRUMENT)$(if $(is-kernel-object),$(CONFIG_KCOV_INSTRUMENT_ALL))), \
176 $(CFLAGS_KCOV))
177endif
178
179#
180# Enable KCSAN flags except some files or directories we don't want to check
181# (depends on variables KCSAN_SANITIZE_obj.o, KCSAN_SANITIZE)
182#
183ifeq ($(CONFIG_KCSAN),y)
184_c_flags += $(if $(patsubst n%,, \
185 $(KCSAN_SANITIZE_$(target-stem).o)$(KCSAN_SANITIZE)$(is-kernel-object)), \
186 $(CFLAGS_KCSAN))
187# Some uninstrumented files provide implied barriers required to avoid false
188# positives: set KCSAN_INSTRUMENT_BARRIERS for barrier instrumentation only.
189_c_flags += $(if $(patsubst n%,, \
190 $(KCSAN_INSTRUMENT_BARRIERS_$(target-stem).o)$(KCSAN_INSTRUMENT_BARRIERS)n), \
191 -D__KCSAN_INSTRUMENT_BARRIERS__)
192endif
193
194#
195# Enable AutoFDO build flags except some files or directories we don't want to
196# enable (depends on variables AUTOFDO_PROFILE_obj.o and AUTOFDO_PROFILE).
197#
198ifeq ($(CONFIG_AUTOFDO_CLANG),y)
199_c_flags += $(if $(patsubst n%,, \
200 $(AUTOFDO_PROFILE_$(target-stem).o)$(AUTOFDO_PROFILE)$(is-kernel-object)), \
201 $(CFLAGS_AUTOFDO_CLANG))
202endif
203
204#
205# Enable Propeller build flags except some files or directories we don't want to
206# enable (depends on variables AUTOFDO_PROPELLER_obj.o and PROPELLER_PROFILE).
207#
208ifdef CONFIG_PROPELLER_CLANG
209_c_flags += $(if $(patsubst n%,, \
210 $(AUTOFDO_PROFILE_$(target-stem).o)$(AUTOFDO_PROFILE)$(PROPELLER_PROFILE))$(is-kernel-object), \
211 $(CFLAGS_PROPELLER_CLANG))
212endif
213
214# $(src) for including checkin headers from generated source files
215# $(obj) for including generated headers from checkin source files
216ifdef building_out_of_srctree
217_c_flags += $(addprefix -I, $(src) $(obj))
218_a_flags += $(addprefix -I, $(src) $(obj))
219_cpp_flags += $(addprefix -I, $(src) $(obj))
220endif
221
222# If $(is-kernel-object) is 'y', this object will be linked to vmlinux or modules
223is-kernel-object = $(or $(part-of-builtin),$(part-of-module))
224
225part-of-builtin = $(if $(filter $(basename $@).o, $(real-obj-y) $(lib-y)),y)
226part-of-module = $(if $(filter $(basename $@).o, $(real-obj-m)),y)
227quiet_modtag = $(if $(part-of-module),[M], )
228
229modkern_cflags = \
230 $(if $(part-of-module), \
231 $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
232 $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL) $(modfile_flags))
233
234modkern_rustflags = \
235 $(if $(part-of-module), \
236 $(KBUILD_RUSTFLAGS_MODULE) $(RUSTFLAGS_MODULE), \
237 $(KBUILD_RUSTFLAGS_KERNEL) $(RUSTFLAGS_KERNEL))
238
239modkern_aflags = $(if $(part-of-module), \
240 $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE), \
241 $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL) $(modfile_flags))
242
243c_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
244 -include $(srctree)/include/linux/compiler_types.h \
245 $(_c_flags) $(modkern_cflags) \
246 $(basename_flags) $(modname_flags)
247
248rust_flags = $(_rust_flags) $(modkern_rustflags) @$(objtree)/include/generated/rustc_cfg
249
250a_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
251 $(_a_flags) $(modkern_aflags) $(modname_flags)
252
253cpp_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
254 $(_cpp_flags)
255
256ld_flags = $(KBUILD_LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F))
257
258ifdef CONFIG_OBJTOOL
259
260objtool := $(objtree)/tools/objtool/objtool
261
262objtool-args-$(CONFIG_HAVE_JUMP_LABEL_HACK) += --hacks=jump_label
263objtool-args-$(CONFIG_HAVE_NOINSTR_HACK) += --hacks=noinstr
264objtool-args-$(CONFIG_MITIGATION_CALL_DEPTH_TRACKING) += --hacks=skylake
265objtool-args-$(CONFIG_X86_KERNEL_IBT) += --ibt
266objtool-args-$(CONFIG_FINEIBT) += --cfi
267objtool-args-$(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL) += --mcount
268ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
269objtool-args-$(CONFIG_HAVE_OBJTOOL_NOP_MCOUNT) += --mnop
270endif
271objtool-args-$(CONFIG_UNWINDER_ORC) += --orc
272objtool-args-$(CONFIG_MITIGATION_RETPOLINE) += --retpoline
273objtool-args-$(CONFIG_MITIGATION_RETHUNK) += --rethunk
274objtool-args-$(CONFIG_MITIGATION_SLS) += --sls
275objtool-args-$(CONFIG_STACK_VALIDATION) += --stackval
276objtool-args-$(CONFIG_HAVE_STATIC_CALL_INLINE) += --static-call
277objtool-args-$(CONFIG_HAVE_UACCESS_VALIDATION) += --uaccess
278objtool-args-$(CONFIG_GCOV_KERNEL) += --no-unreachable
279objtool-args-$(CONFIG_PREFIX_SYMBOLS) += --prefix=$(CONFIG_FUNCTION_PADDING_BYTES)
280
281objtool-args = $(objtool-args-y) \
282 $(if $(delay-objtool), --link) \
283 $(if $(part-of-module), --module)
284
285delay-objtool := $(or $(CONFIG_LTO_CLANG),$(CONFIG_X86_KERNEL_IBT))
286
287cmd_objtool = $(if $(objtool-enabled), ; $(objtool) $(objtool-args) $@)
288cmd_gen_objtooldep = $(if $(objtool-enabled), { echo ; echo '$@: $$(wildcard $(objtool))' ; } >> $(dot-target).cmd)
289
290objtool-enabled := y
291
292endif # CONFIG_OBJTOOL
293
294# Useful for describing the dependency of composite objects
295# Usage:
296# $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add)
297define multi_depend
298$(foreach m, $1, \
299 $(eval $m: \
300 $(addprefix $(obj)/, $(call suffix-search, $(patsubst $(obj)/%,%,$m), $2, $3))))
301endef
302
303# Build commands
304# ===========================================================================
305# These are shared by some Makefile.* files.
306
307ifdef CONFIG_LTO_CLANG
308# Run $(LD) here to covert LLVM IR to ELF in the following cases:
309# - when this object needs objtool processing, as objtool cannot process LLVM IR
310# - when this is a single-object module, as modpost cannot process LLVM IR
311cmd_ld_single = $(if $(objtool-enabled)$(is-single-obj-m), ; $(LD) $(ld_flags) -r -o $(tmp-target) $@; mv $(tmp-target) $@)
312endif
313
314quiet_cmd_cc_o_c = CC $(quiet_modtag) $@
315 cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $< \
316 $(cmd_ld_single) \
317 $(cmd_objtool)
318
319define rule_cc_o_c
320 $(call cmd_and_fixdep,cc_o_c)
321 $(call cmd,checksrc)
322 $(call cmd,checkdoc)
323 $(call cmd,gen_objtooldep)
324 $(call cmd,gen_symversions_c)
325 $(call cmd,record_mcount)
326 $(call cmd,warn_shared_object)
327endef
328
329quiet_cmd_as_o_S = AS $(quiet_modtag) $@
330 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $< $(cmd_objtool)
331
332define rule_as_o_S
333 $(call cmd_and_fixdep,as_o_S)
334 $(call cmd,gen_objtooldep)
335 $(call cmd,gen_symversions_S)
336 $(call cmd,warn_shared_object)
337endef
338
339# Copy a file
340# ===========================================================================
341# 'cp' preserves permissions. If you use it to copy a file in read-only srctree,
342# the copy would be read-only as well, leading to an error when executing the
343# rule next time. Use 'cat' instead in order to generate a writable file.
344quiet_cmd_copy = COPY $@
345 cmd_copy = cat $< > $@
346
347$(obj)/%: $(src)/%_shipped
348 $(call cmd,copy)
349
350# Commands useful for building a boot image
351# ===========================================================================
352#
353# Use as following:
354#
355# target: source(s) FORCE
356# $(if_changed,ld/objcopy/gzip)
357#
358# and add target to 'targets' so that we know we have to
359# read in the saved command line
360
361# Linking
362# ---------------------------------------------------------------------------
363
364quiet_cmd_ld = LD $@
365 cmd_ld = $(LD) $(ld_flags) $(real-prereqs) -o $@
366
367# Archive
368# ---------------------------------------------------------------------------
369
370quiet_cmd_ar = AR $@
371 cmd_ar = rm -f $@; $(AR) cDPrsT $@ $(real-prereqs)
372
373# Objcopy
374# ---------------------------------------------------------------------------
375
376quiet_cmd_objcopy = OBJCOPY $@
377cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@
378
379# Gzip
380# ---------------------------------------------------------------------------
381
382quiet_cmd_gzip = GZIP $@
383 cmd_gzip = cat $(real-prereqs) | $(KGZIP) -n -f -9 > $@
384
385# Bzip2
386# ---------------------------------------------------------------------------
387
388# Bzip2 and LZMA do not include size in file... so we have to fake that;
389# append the size as a 32-bit littleendian number as gzip does.
390size_append = printf $(shell \
391dec_size=0; \
392for F in $(real-prereqs); do \
393 fsize=$$($(CONFIG_SHELL) $(srctree)/scripts/file-size.sh $$F); \
394 dec_size=$$(expr $$dec_size + $$fsize); \
395done; \
396printf "%08x\n" $$dec_size | \
397 sed 's/\(..\)/\1 /g' | { \
398 read ch0 ch1 ch2 ch3; \
399 for ch in $$ch3 $$ch2 $$ch1 $$ch0; do \
400 printf '%s%03o' '\\' $$((0x$$ch)); \
401 done; \
402 } \
403)
404
405quiet_cmd_file_size = GEN $@
406 cmd_file_size = $(size_append) > $@
407
408quiet_cmd_bzip2 = BZIP2 $@
409 cmd_bzip2 = cat $(real-prereqs) | $(KBZIP2) -9 > $@
410
411quiet_cmd_bzip2_with_size = BZIP2 $@
412 cmd_bzip2_with_size = { cat $(real-prereqs) | $(KBZIP2) -9; $(size_append); } > $@
413
414# Lzma
415# ---------------------------------------------------------------------------
416
417quiet_cmd_lzma = LZMA $@
418 cmd_lzma = cat $(real-prereqs) | $(LZMA) -9 > $@
419
420quiet_cmd_lzma_with_size = LZMA $@
421 cmd_lzma_with_size = { cat $(real-prereqs) | $(LZMA) -9; $(size_append); } > $@
422
423quiet_cmd_lzo = LZO $@
424 cmd_lzo = cat $(real-prereqs) | $(KLZOP) -9 > $@
425
426quiet_cmd_lzo_with_size = LZO $@
427 cmd_lzo_with_size = { cat $(real-prereqs) | $(KLZOP) -9; $(size_append); } > $@
428
429quiet_cmd_lz4 = LZ4 $@
430 cmd_lz4 = cat $(real-prereqs) | $(LZ4) -l -9 - - > $@
431
432quiet_cmd_lz4_with_size = LZ4 $@
433 cmd_lz4_with_size = { cat $(real-prereqs) | $(LZ4) -l -9 - -; \
434 $(size_append); } > $@
435
436# U-Boot mkimage
437# ---------------------------------------------------------------------------
438
439MKIMAGE := $(srctree)/scripts/mkuboot.sh
440
441# SRCARCH just happens to match slightly more than ARCH (on sparc), so reduces
442# the number of overrides in arch makefiles
443UIMAGE_ARCH ?= $(SRCARCH)
444UIMAGE_COMPRESSION ?= $(or $(2),none)
445UIMAGE_OPTS-y ?=
446UIMAGE_TYPE ?= kernel
447UIMAGE_LOADADDR ?= arch_must_set_this
448UIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR)
449UIMAGE_NAME ?= Linux-$(KERNELRELEASE)
450
451quiet_cmd_uimage = UIMAGE $@
452 cmd_uimage = $(BASH) $(MKIMAGE) -A $(UIMAGE_ARCH) -O linux \
453 -C $(UIMAGE_COMPRESSION) $(UIMAGE_OPTS-y) \
454 -T $(UIMAGE_TYPE) \
455 -a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \
456 -n '$(UIMAGE_NAME)' -d $< $@
457
458# Flat Image Tree (FIT)
459# This allows for packaging of a kernel and all devicetrees files, using
460# compression.
461# ---------------------------------------------------------------------------
462
463MAKE_FIT := $(srctree)/scripts/make_fit.py
464
465# Use this to override the compression algorithm
466FIT_COMPRESSION ?= gzip
467
468quiet_cmd_fit = FIT $@
469 cmd_fit = $(MAKE_FIT) -o $@ --arch $(UIMAGE_ARCH) --os linux \
470 --name '$(UIMAGE_NAME)' \
471 $(if $(findstring 1,$(KBUILD_VERBOSE)),-v) \
472 $(if $(FIT_DECOMPOSE_DTBS),--decompose-dtbs) \
473 --compress $(FIT_COMPRESSION) -k $< @$(word 2,$^)
474
475# XZ
476# ---------------------------------------------------------------------------
477# Use xzkern or xzkern_with_size to compress the kernel image and xzmisc to
478# compress other things.
479#
480# xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage
481# of the kernel decompressor. A BCJ filter is used if it is available for
482# the target architecture.
483#
484# xzkern_with_size also appends uncompressed size of the data using
485# size_append. The .xz format has the size information available at the end
486# of the file too, but it's in more complex format and it's good to avoid
487# changing the part of the boot code that reads the uncompressed size.
488# Note that the bytes added by size_append will make the xz tool think that
489# the file is corrupt. This is expected.
490#
491# xzmisc doesn't use size_append, so it can be used to create normal .xz
492# files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very
493# big dictionary would increase the memory usage too much in the multi-call
494# decompression mode. A BCJ filter isn't used either.
495quiet_cmd_xzkern = XZKERN $@
496 cmd_xzkern = cat $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh > $@
497
498quiet_cmd_xzkern_with_size = XZKERN $@
499 cmd_xzkern_with_size = { cat $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh; \
500 $(size_append); } > $@
501
502quiet_cmd_xzmisc = XZMISC $@
503 cmd_xzmisc = cat $(real-prereqs) | $(XZ) --check=crc32 --lzma2=dict=1MiB > $@
504
505# ZSTD
506# ---------------------------------------------------------------------------
507# Appends the uncompressed size of the data using size_append. The .zst
508# format has the size information available at the beginning of the file too,
509# but it's in a more complex format and it's good to avoid changing the part
510# of the boot code that reads the uncompressed size.
511#
512# Note that the bytes added by size_append will make the zstd tool think that
513# the file is corrupt. This is expected.
514#
515# zstd uses a maximum window size of 8 MB. zstd22 uses a maximum window size of
516# 128 MB. zstd22 is used for kernel compression because it is decompressed in a
517# single pass, so zstd doesn't need to allocate a window buffer. When streaming
518# decompression is used, like initramfs decompression, zstd22 should likely not
519# be used because it would require zstd to allocate a 128 MB buffer.
520
521quiet_cmd_zstd = ZSTD $@
522 cmd_zstd = cat $(real-prereqs) | $(ZSTD) -19 > $@
523
524quiet_cmd_zstd22 = ZSTD22 $@
525 cmd_zstd22 = cat $(real-prereqs) | $(ZSTD) -22 --ultra > $@
526
527quiet_cmd_zstd22_with_size = ZSTD22 $@
528 cmd_zstd22_with_size = { cat $(real-prereqs) | $(ZSTD) -22 --ultra; $(size_append); } > $@
529
530# ASM offsets
531# ---------------------------------------------------------------------------
532
533# Default sed regexp - multiline due to syntax constraints
534#
535# Use [:space:] because LLVM's integrated assembler inserts <tab> around
536# the .ascii directive whereas GCC keeps the <space> as-is.
537define sed-offsets
538 's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \
539 /^->/{s:->#\(.*\):/* \1 */:; \
540 s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
541 s:->::; p;}'
542endef
543
544# Use filechk to avoid rebuilds when a header changes, but the resulting file
545# does not
546define filechk_offsets
547 echo "#ifndef $2"; \
548 echo "#define $2"; \
549 echo "/*"; \
550 echo " * DO NOT MODIFY."; \
551 echo " *"; \
552 echo " * This file was generated by Kbuild"; \
553 echo " */"; \
554 echo ""; \
555 sed -ne $(sed-offsets) < $<; \
556 echo ""; \
557 echo "#endif"
558endef