xref: /openbmc/linux/Makefile (revision 1634f2bf)
1# SPDX-License-Identifier: GPL-2.0
2VERSION = 5
3PATCHLEVEL = 3
4SUBLEVEL = 0
5EXTRAVERSION = -rc4
6NAME = Bobtail Squid
7
8# *DOCUMENTATION*
9# To see a list of typical targets execute "make help"
10# More info can be located in ./README
11# Comments in this file are targeted only to the developer, do not
12# expect to learn how to build the kernel reading this file.
13
14# That's our default target when none is given on the command line
15PHONY := _all
16_all:
17
18# We are using a recursive build, so we need to do a little thinking
19# to get the ordering right.
20#
21# Most importantly: sub-Makefiles should only ever modify files in
22# their own directory. If in some directory we have a dependency on
23# a file in another dir (which doesn't happen often, but it's often
24# unavoidable when linking the built-in.a targets which finally
25# turn into vmlinux), we will call a sub make in that other dir, and
26# after that we are sure that everything which is in that other dir
27# is now up to date.
28#
29# The only cases where we need to modify files which have global
30# effects are thus separated out and done before the recursive
31# descending is started. They are now explicitly listed as the
32# prepare rule.
33
34ifneq ($(sub_make_done),1)
35
36# Do not use make's built-in rules and variables
37# (this increases performance and avoids hard-to-debug behaviour)
38MAKEFLAGS += -rR
39
40# Avoid funny character set dependencies
41unexport LC_ALL
42LC_COLLATE=C
43LC_NUMERIC=C
44export LC_COLLATE LC_NUMERIC
45
46# Avoid interference with shell env settings
47unexport GREP_OPTIONS
48
49# Beautify output
50# ---------------------------------------------------------------------------
51#
52# Normally, we echo the whole command before executing it. By making
53# that echo $($(quiet)$(cmd)), we now have the possibility to set
54# $(quiet) to choose other forms of output instead, e.g.
55#
56#         quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
57#         cmd_cc_o_c       = $(CC) $(c_flags) -c -o $@ $<
58#
59# If $(quiet) is empty, the whole command will be printed.
60# If it is set to "quiet_", only the short version will be printed.
61# If it is set to "silent_", nothing will be printed at all, since
62# the variable $(silent_cmd_cc_o_c) doesn't exist.
63#
64# A simple variant is to prefix commands with $(Q) - that's useful
65# for commands that shall be hidden in non-verbose mode.
66#
67#	$(Q)ln $@ :<
68#
69# If KBUILD_VERBOSE equals 0 then the above command will be hidden.
70# If KBUILD_VERBOSE equals 1 then the above command is displayed.
71#
72# To put more focus on warnings, be less verbose as default
73# Use 'make V=1' to see the full commands
74
75ifeq ("$(origin V)", "command line")
76  KBUILD_VERBOSE = $(V)
77endif
78ifndef KBUILD_VERBOSE
79  KBUILD_VERBOSE = 0
80endif
81
82ifeq ($(KBUILD_VERBOSE),1)
83  quiet =
84  Q =
85else
86  quiet=quiet_
87  Q = @
88endif
89
90# If the user is running make -s (silent mode), suppress echoing of
91# commands
92
93ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
94  quiet=silent_
95endif
96
97export quiet Q KBUILD_VERBOSE
98
99# Kbuild will save output files in the current working directory.
100# This does not need to match to the root of the kernel source tree.
101#
102# For example, you can do this:
103#
104#  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
105#
106# If you want to save output files in a different location, there are
107# two syntaxes to specify it.
108#
109# 1) O=
110# Use "make O=dir/to/store/output/files/"
111#
112# 2) Set KBUILD_OUTPUT
113# Set the environment variable KBUILD_OUTPUT to point to the output directory.
114# export KBUILD_OUTPUT=dir/to/store/output/files/; make
115#
116# The O= assignment takes precedence over the KBUILD_OUTPUT environment
117# variable.
118
119# Do we want to change the working directory?
120ifeq ("$(origin O)", "command line")
121  KBUILD_OUTPUT := $(O)
122endif
123
124ifneq ($(KBUILD_OUTPUT),)
125# Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
126# expand a shell special character '~'. We use a somewhat tedious way here.
127abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
128$(if $(abs_objtree),, \
129     $(error failed to create output directory "$(KBUILD_OUTPUT)"))
130
131# $(realpath ...) resolves symlinks
132abs_objtree := $(realpath $(abs_objtree))
133else
134abs_objtree := $(CURDIR)
135endif # ifneq ($(KBUILD_OUTPUT),)
136
137ifeq ($(abs_objtree),$(CURDIR))
138# Suppress "Entering directory ..." unless we are changing the work directory.
139MAKEFLAGS += --no-print-directory
140else
141need-sub-make := 1
142endif
143
144abs_srctree := $(realpath $(dir $(lastword $(MAKEFILE_LIST))))
145
146ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
147$(error source directory cannot contain spaces or colons)
148endif
149
150ifneq ($(abs_srctree),$(abs_objtree))
151# Look for make include files relative to root of kernel src
152#
153# This does not become effective immediately because MAKEFLAGS is re-parsed
154# once after the Makefile is read. We need to invoke sub-make.
155MAKEFLAGS += --include-dir=$(abs_srctree)
156need-sub-make := 1
157endif
158
159ifneq ($(filter 3.%,$(MAKE_VERSION)),)
160# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
161# We need to invoke sub-make to avoid implicit rules in the top Makefile.
162need-sub-make := 1
163# Cancel implicit rules for this Makefile.
164$(lastword $(MAKEFILE_LIST)): ;
165endif
166
167export abs_srctree abs_objtree
168export sub_make_done := 1
169
170ifeq ($(need-sub-make),1)
171
172PHONY += $(MAKECMDGOALS) sub-make
173
174$(filter-out _all sub-make $(lastword $(MAKEFILE_LIST)), $(MAKECMDGOALS)) _all: sub-make
175	@:
176
177# Invoke a second make in the output directory, passing relevant variables
178sub-make:
179	$(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
180
181endif # need-sub-make
182endif # sub_make_done
183
184# We process the rest of the Makefile if this is the final invocation of make
185ifeq ($(need-sub-make),)
186
187# Do not print "Entering directory ...",
188# but we want to display it when entering to the output directory
189# so that IDEs/editors are able to understand relative filenames.
190MAKEFLAGS += --no-print-directory
191
192# Call a source code checker (by default, "sparse") as part of the
193# C compilation.
194#
195# Use 'make C=1' to enable checking of only re-compiled files.
196# Use 'make C=2' to enable checking of *all* source files, regardless
197# of whether they are re-compiled or not.
198#
199# See the file "Documentation/dev-tools/sparse.rst" for more details,
200# including where to get the "sparse" utility.
201
202ifeq ("$(origin C)", "command line")
203  KBUILD_CHECKSRC = $(C)
204endif
205ifndef KBUILD_CHECKSRC
206  KBUILD_CHECKSRC = 0
207endif
208
209# Use make M=dir to specify directory of external module to build
210# Old syntax make ... SUBDIRS=$PWD is still supported
211# Setting the environment variable KBUILD_EXTMOD take precedence
212ifdef SUBDIRS
213  $(warning ================= WARNING ================)
214  $(warning 'SUBDIRS' will be removed after Linux 5.3)
215  $(warning )
216  $(warning If you are building an individual subdirectory)
217  $(warning in the kernel tree, you can do like this:)
218  $(warning $$ make path/to/dir/you/want/to/build/)
219  $(warning (Do not forget the trailing slash))
220  $(warning )
221  $(warning If you are building an external module,)
222  $(warning Please use 'M=' or 'KBUILD_EXTMOD' instead)
223  $(warning ==========================================)
224  KBUILD_EXTMOD ?= $(SUBDIRS)
225endif
226
227ifeq ("$(origin M)", "command line")
228  KBUILD_EXTMOD := $(M)
229endif
230
231export KBUILD_CHECKSRC KBUILD_EXTMOD
232
233extmod-prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
234
235ifeq ($(abs_srctree),$(abs_objtree))
236        # building in the source tree
237        srctree := .
238	building_out_of_srctree :=
239else
240        ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
241                # building in a subdirectory of the source tree
242                srctree := ..
243        else
244                srctree := $(abs_srctree)
245        endif
246	building_out_of_srctree := 1
247endif
248
249ifneq ($(KBUILD_ABS_SRCTREE),)
250srctree := $(abs_srctree)
251endif
252
253objtree		:= .
254VPATH		:= $(srctree)
255
256export building_out_of_srctree srctree objtree VPATH
257
258# To make sure we do not include .config for any of the *config targets
259# catch them early, and hand them over to scripts/kconfig/Makefile
260# It is allowed to specify more targets when calling make, including
261# mixing *config targets and build targets.
262# For example 'make oldconfig all'.
263# Detect when mixed targets is specified, and make a second invocation
264# of make so .config is not included in this case either (for *config).
265
266version_h := include/generated/uapi/linux/version.h
267old_version_h := include/linux/version.h
268
269clean-targets := %clean mrproper cleandocs
270no-dot-config-targets := $(clean-targets) \
271			 cscope gtags TAGS tags help% %docs check% coccicheck \
272			 $(version_h) headers headers_% archheaders archscripts \
273			 %asm-generic kernelversion %src-pkg
274no-sync-config-targets := $(no-dot-config-targets) install %install \
275			   kernelrelease
276single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
277
278config-build	:=
279mixed-build	:=
280need-config	:= 1
281may-sync-config	:= 1
282single-build	:=
283
284ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
285	ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
286		need-config :=
287	endif
288endif
289
290ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
291	ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
292		may-sync-config :=
293	endif
294endif
295
296ifneq ($(KBUILD_EXTMOD),)
297	may-sync-config :=
298endif
299
300ifeq ($(KBUILD_EXTMOD),)
301        ifneq ($(filter config %config,$(MAKECMDGOALS)),)
302		config-build := 1
303                ifneq ($(words $(MAKECMDGOALS)),1)
304			mixed-build := 1
305                endif
306        endif
307endif
308
309# We cannot build single targets and the others at the same time
310ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
311	single-build := 1
312	ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
313		mixed-build := 1
314	endif
315endif
316
317# For "make -j clean all", "make -j mrproper defconfig all", etc.
318ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
319        ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
320		mixed-build := 1
321        endif
322endif
323
324# install and modules_install need also be processed one by one
325ifneq ($(filter install,$(MAKECMDGOALS)),)
326        ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
327		mixed-build := 1
328        endif
329endif
330
331ifdef mixed-build
332# ===========================================================================
333# We're called with mixed targets (*config and build targets).
334# Handle them one by one.
335
336PHONY += $(MAKECMDGOALS) __build_one_by_one
337
338$(filter-out __build_one_by_one, $(MAKECMDGOALS)): __build_one_by_one
339	@:
340
341__build_one_by_one:
342	$(Q)set -e; \
343	for i in $(MAKECMDGOALS); do \
344		$(MAKE) -f $(srctree)/Makefile $$i; \
345	done
346
347else # !mixed-build
348
349include scripts/Kbuild.include
350
351# Read KERNELRELEASE from include/config/kernel.release (if it exists)
352KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
353KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
354export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
355
356include scripts/subarch.include
357
358# Cross compiling and selecting different set of gcc/bin-utils
359# ---------------------------------------------------------------------------
360#
361# When performing cross compilation for other architectures ARCH shall be set
362# to the target architecture. (See arch/* for the possibilities).
363# ARCH can be set during invocation of make:
364# make ARCH=ia64
365# Another way is to have ARCH set in the environment.
366# The default ARCH is the host where make is executed.
367
368# CROSS_COMPILE specify the prefix used for all executables used
369# during compilation. Only gcc and related bin-utils executables
370# are prefixed with $(CROSS_COMPILE).
371# CROSS_COMPILE can be set on the command line
372# make CROSS_COMPILE=ia64-linux-
373# Alternatively CROSS_COMPILE can be set in the environment.
374# Default value for CROSS_COMPILE is not to prefix executables
375# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
376ARCH		?= $(SUBARCH)
377
378# Architecture as present in compile.h
379UTS_MACHINE 	:= $(ARCH)
380SRCARCH 	:= $(ARCH)
381
382# Additional ARCH settings for x86
383ifeq ($(ARCH),i386)
384        SRCARCH := x86
385endif
386ifeq ($(ARCH),x86_64)
387        SRCARCH := x86
388endif
389
390# Additional ARCH settings for sparc
391ifeq ($(ARCH),sparc32)
392       SRCARCH := sparc
393endif
394ifeq ($(ARCH),sparc64)
395       SRCARCH := sparc
396endif
397
398# Additional ARCH settings for sh
399ifeq ($(ARCH),sh64)
400       SRCARCH := sh
401endif
402
403KCONFIG_CONFIG	?= .config
404export KCONFIG_CONFIG
405
406# SHELL used by kbuild
407CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
408	  else if [ -x /bin/bash ]; then echo /bin/bash; \
409	  else echo sh; fi ; fi)
410
411HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
412HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
413HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
414
415HOSTCC       = gcc
416HOSTCXX      = g++
417KBUILD_HOSTCFLAGS   := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
418		-fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS) \
419		$(HOSTCFLAGS)
420KBUILD_HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
421KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
422KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
423
424# Make variables (CC, etc...)
425AS		= $(CROSS_COMPILE)as
426LD		= $(CROSS_COMPILE)ld
427CC		= $(CROSS_COMPILE)gcc
428CPP		= $(CC) -E
429AR		= $(CROSS_COMPILE)ar
430NM		= $(CROSS_COMPILE)nm
431STRIP		= $(CROSS_COMPILE)strip
432OBJCOPY		= $(CROSS_COMPILE)objcopy
433OBJDUMP		= $(CROSS_COMPILE)objdump
434OBJSIZE		= $(CROSS_COMPILE)size
435PAHOLE		= pahole
436LEX		= flex
437YACC		= bison
438AWK		= awk
439INSTALLKERNEL  := installkernel
440DEPMOD		= /sbin/depmod
441PERL		= perl
442PYTHON		= python
443PYTHON2		= python2
444PYTHON3		= python3
445CHECK		= sparse
446
447CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
448		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
449NOSTDINC_FLAGS :=
450CFLAGS_MODULE   =
451AFLAGS_MODULE   =
452LDFLAGS_MODULE  =
453CFLAGS_KERNEL	=
454AFLAGS_KERNEL	=
455LDFLAGS_vmlinux =
456
457# Use USERINCLUDE when you must reference the UAPI directories only.
458USERINCLUDE    := \
459		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
460		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
461		-I$(srctree)/include/uapi \
462		-I$(objtree)/include/generated/uapi \
463                -include $(srctree)/include/linux/kconfig.h
464
465# Use LINUXINCLUDE when you must reference the include/ directory.
466# Needed to be compatible with the O= option
467LINUXINCLUDE    := \
468		-I$(srctree)/arch/$(SRCARCH)/include \
469		-I$(objtree)/arch/$(SRCARCH)/include/generated \
470		$(if $(building_out_of_srctree),-I$(srctree)/include) \
471		-I$(objtree)/include \
472		$(USERINCLUDE)
473
474KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
475KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
476		   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
477		   -Werror=implicit-function-declaration -Werror=implicit-int \
478		   -Wno-format-security \
479		   -std=gnu89
480KBUILD_CPPFLAGS := -D__KERNEL__
481KBUILD_AFLAGS_KERNEL :=
482KBUILD_CFLAGS_KERNEL :=
483KBUILD_AFLAGS_MODULE  := -DMODULE
484KBUILD_CFLAGS_MODULE  := -DMODULE
485KBUILD_LDFLAGS_MODULE :=
486export KBUILD_LDS_MODULE := $(srctree)/scripts/module-common.lds
487KBUILD_LDFLAGS :=
488GCC_PLUGINS_CFLAGS :=
489CLANG_FLAGS :=
490
491export ARCH SRCARCH CONFIG_SHELL HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE AS LD CC
492export CPP AR NM STRIP OBJCOPY OBJDUMP OBJSIZE PAHOLE LEX YACC AWK INSTALLKERNEL
493export PERL PYTHON PYTHON2 PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
494export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
495
496export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
497export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
498export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN
499export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
500export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
501export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
502export KBUILD_ARFLAGS
503
504# Files to ignore in find ... statements
505
506export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
507			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
508			  -prune -o
509export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
510			 --exclude CVS --exclude .pc --exclude .hg --exclude .git
511
512# ===========================================================================
513# Rules shared between *config targets and build targets
514
515# Basic helpers built in scripts/basic/
516PHONY += scripts_basic
517scripts_basic:
518	$(Q)$(MAKE) $(build)=scripts/basic
519	$(Q)rm -f .tmp_quiet_recordmcount
520
521PHONY += outputmakefile
522# Before starting out-of-tree build, make sure the source tree is clean.
523# outputmakefile generates a Makefile in the output directory, if using a
524# separate output directory. This allows convenient use of make in the
525# output directory.
526# At the same time when output Makefile generated, generate .gitignore to
527# ignore whole output directory
528outputmakefile:
529ifdef building_out_of_srctree
530	$(Q)if [ -f $(srctree)/.config -o \
531		 -d $(srctree)/include/config -o \
532		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
533		echo >&2 "***"; \
534		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
535		echo >&2 "*** in $(abs_srctree)";\
536		echo >&2 "***"; \
537		false; \
538	fi
539	$(Q)ln -fsn $(srctree) source
540	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
541	$(Q)test -e .gitignore || \
542	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
543endif
544
545ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
546ifneq ($(CROSS_COMPILE),)
547CLANG_FLAGS	+= --target=$(notdir $(CROSS_COMPILE:%-=%))
548GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
549CLANG_FLAGS	+= --prefix=$(GCC_TOOLCHAIN_DIR)
550GCC_TOOLCHAIN	:= $(realpath $(GCC_TOOLCHAIN_DIR)/..)
551endif
552ifneq ($(GCC_TOOLCHAIN),)
553CLANG_FLAGS	+= --gcc-toolchain=$(GCC_TOOLCHAIN)
554endif
555ifeq ($(shell $(AS) --version 2>&1 | head -n 1 | grep clang),)
556CLANG_FLAGS	+= -no-integrated-as
557endif
558CLANG_FLAGS	+= -Werror=unknown-warning-option
559KBUILD_CFLAGS	+= $(CLANG_FLAGS)
560KBUILD_AFLAGS	+= $(CLANG_FLAGS)
561export CLANG_FLAGS
562endif
563
564# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
565# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
566# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
567# and from include/config/auto.conf.cmd to detect the compiler upgrade.
568CC_VERSION_TEXT = $(shell $(CC) --version 2>/dev/null | head -n 1)
569
570ifdef config-build
571# ===========================================================================
572# *config targets only - make sure prerequisites are updated, and descend
573# in scripts/kconfig to make the *config target
574
575# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
576# KBUILD_DEFCONFIG may point out an alternative default configuration
577# used for 'make defconfig'
578include arch/$(SRCARCH)/Makefile
579export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
580
581config: outputmakefile scripts_basic FORCE
582	$(Q)$(MAKE) $(build)=scripts/kconfig $@
583
584%config: outputmakefile scripts_basic FORCE
585	$(Q)$(MAKE) $(build)=scripts/kconfig $@
586
587else #!config-build
588# ===========================================================================
589# Build targets only - this includes vmlinux, arch specific targets, clean
590# targets and others. In general all targets except *config targets.
591
592# If building an external module we do not care about the all: rule
593# but instead _all depend on modules
594PHONY += all
595ifeq ($(KBUILD_EXTMOD),)
596_all: all
597else
598_all: modules
599endif
600
601# Decide whether to build built-in, modular, or both.
602# Normally, just do built-in.
603
604KBUILD_MODULES :=
605KBUILD_BUILTIN := 1
606
607# If we have only "make modules", don't compile built-in objects.
608# When we're building modules with modversions, we need to consider
609# the built-in objects during the descend as well, in order to
610# make sure the checksums are up to date before we record them.
611
612ifeq ($(MAKECMDGOALS),modules)
613  KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
614endif
615
616# If we have "make <whatever> modules", compile modules
617# in addition to whatever we do anyway.
618# Just "make" or "make all" shall build modules as well
619
620ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
621  KBUILD_MODULES := 1
622endif
623
624ifeq ($(MAKECMDGOALS),)
625  KBUILD_MODULES := 1
626endif
627
628export KBUILD_MODULES KBUILD_BUILTIN
629
630ifdef need-config
631include include/config/auto.conf
632endif
633
634ifeq ($(KBUILD_EXTMOD),)
635# Objects we will link into vmlinux / subdirs we need to visit
636init-y		:= init/
637drivers-y	:= drivers/ sound/
638drivers-$(CONFIG_SAMPLES) += samples/
639drivers-$(CONFIG_KERNEL_HEADER_TEST) += include/
640net-y		:= net/
641libs-y		:= lib/
642core-y		:= usr/
643virt-y		:= virt/
644endif # KBUILD_EXTMOD
645
646# The all: target is the default when no target is given on the
647# command line.
648# This allow a user to issue only 'make' to build a kernel including modules
649# Defaults to vmlinux, but the arch makefile usually adds further targets
650all: vmlinux
651
652CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage \
653	$(call cc-option,-fno-tree-loop-im) \
654	$(call cc-disable-warning,maybe-uninitialized,)
655export CFLAGS_GCOV
656
657# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
658ifdef CONFIG_FUNCTION_TRACER
659  CC_FLAGS_FTRACE := -pg
660endif
661
662RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
663RETPOLINE_VDSO_CFLAGS_GCC := -mindirect-branch=thunk-inline -mindirect-branch-register
664RETPOLINE_CFLAGS_CLANG := -mretpoline-external-thunk
665RETPOLINE_VDSO_CFLAGS_CLANG := -mretpoline
666RETPOLINE_CFLAGS := $(call cc-option,$(RETPOLINE_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_CFLAGS_CLANG)))
667RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc-option,$(RETPOLINE_VDSO_CFLAGS_CLANG)))
668export RETPOLINE_CFLAGS
669export RETPOLINE_VDSO_CFLAGS
670
671# The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default
672# values of the respective KBUILD_* variables
673ARCH_CPPFLAGS :=
674ARCH_AFLAGS :=
675ARCH_CFLAGS :=
676include arch/$(SRCARCH)/Makefile
677
678ifdef need-config
679ifdef may-sync-config
680# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
681# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
682# because some architectures define CROSS_COMPILE there.
683include include/config/auto.conf.cmd
684
685$(KCONFIG_CONFIG):
686	@echo >&2 '***'
687	@echo >&2 '*** Configuration file "$@" not found!'
688	@echo >&2 '***'
689	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
690	@echo >&2 '*** "make menuconfig" or "make xconfig").'
691	@echo >&2 '***'
692	@/bin/false
693
694# The actual configuration files used during the build are stored in
695# include/generated/ and include/config/. Update them if .config is newer than
696# include/config/auto.conf (which mirrors .config).
697#
698# This exploits the 'multi-target pattern rule' trick.
699# The syncconfig should be executed only once to make all the targets.
700%/auto.conf %/auto.conf.cmd %/tristate.conf: $(KCONFIG_CONFIG)
701	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
702else # !may-sync-config
703# External modules and some install targets need include/generated/autoconf.h
704# and include/config/auto.conf but do not care if they are up-to-date.
705# Use auto.conf to trigger the test
706PHONY += include/config/auto.conf
707
708include/config/auto.conf:
709	$(Q)test -e include/generated/autoconf.h -a -e $@ || (		\
710	echo >&2;							\
711	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
712	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
713	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
714	echo >&2 ;							\
715	/bin/false)
716
717endif # may-sync-config
718endif # need-config
719
720KBUILD_CFLAGS	+= $(call cc-option,-fno-delete-null-pointer-checks,)
721KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
722KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
723KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
724KBUILD_CFLAGS	+= $(call cc-disable-warning, address-of-packed-member)
725
726ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
727KBUILD_CFLAGS	+= -Os
728else
729KBUILD_CFLAGS   += -O2
730endif
731
732ifdef CONFIG_CC_DISABLE_WARN_MAYBE_UNINITIALIZED
733KBUILD_CFLAGS   += -Wno-maybe-uninitialized
734endif
735
736# Tell gcc to never replace conditional load with a non-conditional one
737KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
738
739include scripts/Makefile.kcov
740include scripts/Makefile.gcc-plugins
741
742ifdef CONFIG_READABLE_ASM
743# Disable optimizations that make assembler listings hard to read.
744# reorder blocks reorders the control in the function
745# ipa clone creates specialized cloned functions
746# partial inlining inlines only parts of functions
747KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
748                 $(call cc-option,-fno-ipa-cp-clone,) \
749                 $(call cc-option,-fno-partial-inlining)
750endif
751
752ifneq ($(CONFIG_FRAME_WARN),0)
753KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
754endif
755
756stackp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
757stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
758stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
759
760KBUILD_CFLAGS += $(stackp-flags-y)
761
762ifdef CONFIG_CC_IS_CLANG
763KBUILD_CPPFLAGS += -Qunused-arguments
764KBUILD_CFLAGS += -Wno-format-invalid-specifier
765KBUILD_CFLAGS += -Wno-gnu
766# Quiet clang warning: comparison of unsigned expression < 0 is always false
767KBUILD_CFLAGS += -Wno-tautological-compare
768# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the
769# source of a reference will be _MergedGlobals and not on of the whitelisted names.
770# See modpost pattern 2
771KBUILD_CFLAGS += -mno-global-merge
772else
773
774# These warnings generated too much noise in a regular build.
775# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
776KBUILD_CFLAGS += -Wno-unused-but-set-variable
777endif
778
779KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
780ifdef CONFIG_FRAME_POINTER
781KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
782else
783# Some targets (ARM with Thumb2, for example), can't be built with frame
784# pointers.  For those, we don't have FUNCTION_TRACER automatically
785# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
786# incompatible with -fomit-frame-pointer with current GCC, so we don't use
787# -fomit-frame-pointer with FUNCTION_TRACER.
788ifndef CONFIG_FUNCTION_TRACER
789KBUILD_CFLAGS	+= -fomit-frame-pointer
790endif
791endif
792
793# Initialize all stack variables with a pattern, if desired.
794ifdef CONFIG_INIT_STACK_ALL
795KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
796endif
797
798DEBUG_CFLAGS	:= $(call cc-option, -fno-var-tracking-assignments)
799
800ifdef CONFIG_DEBUG_INFO
801ifdef CONFIG_DEBUG_INFO_SPLIT
802DEBUG_CFLAGS	+= -gsplit-dwarf
803else
804DEBUG_CFLAGS	+= -g
805endif
806KBUILD_AFLAGS	+= -Wa,-gdwarf-2
807endif
808ifdef CONFIG_DEBUG_INFO_DWARF4
809DEBUG_CFLAGS	+= -gdwarf-4
810endif
811
812ifdef CONFIG_DEBUG_INFO_REDUCED
813DEBUG_CFLAGS	+= $(call cc-option, -femit-struct-debug-baseonly) \
814		   $(call cc-option,-fno-var-tracking)
815endif
816
817KBUILD_CFLAGS += $(DEBUG_CFLAGS)
818export DEBUG_CFLAGS
819
820ifdef CONFIG_FUNCTION_TRACER
821ifdef CONFIG_FTRACE_MCOUNT_RECORD
822  # gcc 5 supports generating the mcount tables directly
823  ifeq ($(call cc-option-yn,-mrecord-mcount),y)
824    CC_FLAGS_FTRACE	+= -mrecord-mcount
825    export CC_USING_RECORD_MCOUNT := 1
826  endif
827  ifdef CONFIG_HAVE_NOP_MCOUNT
828    ifeq ($(call cc-option-yn, -mnop-mcount),y)
829      CC_FLAGS_FTRACE	+= -mnop-mcount
830      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
831    endif
832  endif
833endif
834ifdef CONFIG_HAVE_FENTRY
835  ifeq ($(call cc-option-yn, -mfentry),y)
836    CC_FLAGS_FTRACE	+= -mfentry
837    CC_FLAGS_USING	+= -DCC_USING_FENTRY
838  endif
839endif
840export CC_FLAGS_FTRACE
841KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
842KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
843ifdef CONFIG_DYNAMIC_FTRACE
844	ifdef CONFIG_HAVE_C_RECORDMCOUNT
845		BUILD_C_RECORDMCOUNT := y
846		export BUILD_C_RECORDMCOUNT
847	endif
848endif
849endif
850
851# We trigger additional mismatches with less inlining
852ifdef CONFIG_DEBUG_SECTION_MISMATCH
853KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
854endif
855
856ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
857KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
858LDFLAGS_vmlinux += --gc-sections
859endif
860
861ifdef CONFIG_LIVEPATCH
862KBUILD_CFLAGS += $(call cc-option, -flive-patching=inline-clone)
863endif
864
865# arch Makefile may override CC so keep this after arch Makefile is included
866NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
867
868# warn about C99 declaration after statement
869KBUILD_CFLAGS += -Wdeclaration-after-statement
870
871# Warn about unmarked fall-throughs in switch statement.
872KBUILD_CFLAGS += $(call cc-option,-Wimplicit-fallthrough,)
873
874# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
875KBUILD_CFLAGS += -Wvla
876
877# disable pointer signed / unsigned warnings in gcc 4.0
878KBUILD_CFLAGS += -Wno-pointer-sign
879
880# disable stringop warnings in gcc 8+
881KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
882
883# disable invalid "can't wrap" optimizations for signed / pointers
884KBUILD_CFLAGS	+= $(call cc-option,-fno-strict-overflow)
885
886# clang sets -fmerge-all-constants by default as optimization, but this
887# is non-conforming behavior for C and in fact breaks the kernel, so we
888# need to disable it here generally.
889KBUILD_CFLAGS	+= $(call cc-option,-fno-merge-all-constants)
890
891# for gcc -fno-merge-all-constants disables everything, but it is fine
892# to have actual conforming behavior enabled.
893KBUILD_CFLAGS	+= $(call cc-option,-fmerge-constants)
894
895# Make sure -fstack-check isn't enabled (like gentoo apparently did)
896KBUILD_CFLAGS  += $(call cc-option,-fno-stack-check,)
897
898# conserve stack if available
899KBUILD_CFLAGS   += $(call cc-option,-fconserve-stack)
900
901# Prohibit date/time macros, which would make the build non-deterministic
902KBUILD_CFLAGS   += $(call cc-option,-Werror=date-time)
903
904# enforce correct pointer usage
905KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
906
907# Require designated initializers for all marked structures
908KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
909
910# change __FILE__ to the relative path from the srctree
911KBUILD_CFLAGS	+= $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
912
913# ensure -fcf-protection is disabled when using retpoline as it is
914# incompatible with -mindirect-branch=thunk-extern
915ifdef CONFIG_RETPOLINE
916KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none)
917endif
918
919# use the deterministic mode of AR if available
920KBUILD_ARFLAGS := $(call ar-option,D)
921
922include scripts/Makefile.kasan
923include scripts/Makefile.extrawarn
924include scripts/Makefile.ubsan
925
926# Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
927# last assignments
928KBUILD_CPPFLAGS += $(ARCH_CPPFLAGS) $(KCPPFLAGS)
929KBUILD_AFLAGS   += $(ARCH_AFLAGS)   $(KAFLAGS)
930KBUILD_CFLAGS   += $(ARCH_CFLAGS)   $(KCFLAGS)
931
932KBUILD_LDFLAGS_MODULE += --build-id
933LDFLAGS_vmlinux += --build-id
934
935ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
936LDFLAGS_vmlinux	+= $(call ld-option, -X,)
937endif
938
939# insure the checker run with the right endianness
940CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
941
942# the checker needs the correct machine size
943CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
944
945# Default kernel image to build when no specific target is given.
946# KBUILD_IMAGE may be overruled on the command line or
947# set in the environment
948# Also any assignments in arch/$(ARCH)/Makefile take precedence over
949# this default value
950export KBUILD_IMAGE ?= vmlinux
951
952#
953# INSTALL_PATH specifies where to place the updated kernel and system map
954# images. Default is /boot, but you can set it to other values
955export	INSTALL_PATH ?= /boot
956
957#
958# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
959# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
960# an argument if needed. Otherwise it defaults to the kernel install path
961#
962export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
963
964#
965# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
966# relocations required by build roots.  This is not defined in the
967# makefile but the argument can be passed to make if needed.
968#
969
970MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
971export MODLIB
972
973#
974# INSTALL_MOD_STRIP, if defined, will cause modules to be
975# stripped after they are installed.  If INSTALL_MOD_STRIP is '1', then
976# the default option --strip-debug will be used.  Otherwise,
977# INSTALL_MOD_STRIP value will be used as the options to the strip command.
978
979ifdef INSTALL_MOD_STRIP
980ifeq ($(INSTALL_MOD_STRIP),1)
981mod_strip_cmd = $(STRIP) --strip-debug
982else
983mod_strip_cmd = $(STRIP) $(INSTALL_MOD_STRIP)
984endif # INSTALL_MOD_STRIP=1
985else
986mod_strip_cmd = true
987endif # INSTALL_MOD_STRIP
988export mod_strip_cmd
989
990# CONFIG_MODULE_COMPRESS, if defined, will cause module to be compressed
991# after they are installed in agreement with CONFIG_MODULE_COMPRESS_GZIP
992# or CONFIG_MODULE_COMPRESS_XZ.
993
994mod_compress_cmd = true
995ifdef CONFIG_MODULE_COMPRESS
996  ifdef CONFIG_MODULE_COMPRESS_GZIP
997    mod_compress_cmd = gzip -n -f
998  endif # CONFIG_MODULE_COMPRESS_GZIP
999  ifdef CONFIG_MODULE_COMPRESS_XZ
1000    mod_compress_cmd = xz -f
1001  endif # CONFIG_MODULE_COMPRESS_XZ
1002endif # CONFIG_MODULE_COMPRESS
1003export mod_compress_cmd
1004
1005ifdef CONFIG_MODULE_SIG_ALL
1006$(eval $(call config_filename,MODULE_SIG_KEY))
1007
1008mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODULE_SIG_KEY_SRCPREFIX)$(CONFIG_MODULE_SIG_KEY) certs/signing_key.x509
1009else
1010mod_sign_cmd = true
1011endif
1012export mod_sign_cmd
1013
1014HOST_LIBELF_LIBS = $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
1015
1016ifdef CONFIG_STACK_VALIDATION
1017  has_libelf := $(call try-run,\
1018		echo "int main() {}" | $(HOSTCC) -xc -o /dev/null $(HOST_LIBELF_LIBS) -,1,0)
1019  ifeq ($(has_libelf),1)
1020    objtool_target := tools/objtool FORCE
1021  else
1022    SKIP_STACK_VALIDATION := 1
1023    export SKIP_STACK_VALIDATION
1024  endif
1025endif
1026
1027PHONY += prepare0
1028
1029export MODORDER := $(extmod-prefix)modules.order
1030
1031ifeq ($(KBUILD_EXTMOD),)
1032core-y		+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
1033
1034vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, $(init-y) $(init-m) \
1035		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1036		     $(net-y) $(net-m) $(libs-y) $(libs-m) $(virt-y)))
1037
1038vmlinux-alldirs	:= $(sort $(vmlinux-dirs) Documentation \
1039		     $(patsubst %/,%,$(filter %/, $(init-) $(core-) \
1040			$(drivers-) $(net-) $(libs-) $(virt-))))
1041
1042build-dirs	:= $(vmlinux-dirs)
1043clean-dirs	:= $(vmlinux-alldirs)
1044
1045init-y		:= $(patsubst %/, %/built-in.a, $(init-y))
1046core-y		:= $(patsubst %/, %/built-in.a, $(core-y))
1047drivers-y	:= $(patsubst %/, %/built-in.a, $(drivers-y))
1048net-y		:= $(patsubst %/, %/built-in.a, $(net-y))
1049libs-y1		:= $(patsubst %/, %/lib.a, $(libs-y))
1050libs-y2		:= $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y)))
1051virt-y		:= $(patsubst %/, %/built-in.a, $(virt-y))
1052
1053# Externally visible symbols (used by link-vmlinux.sh)
1054export KBUILD_VMLINUX_OBJS := $(head-y) $(init-y) $(core-y) $(libs-y2) \
1055			      $(drivers-y) $(net-y) $(virt-y)
1056export KBUILD_VMLINUX_LIBS := $(libs-y1)
1057export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1058export LDFLAGS_vmlinux
1059# used by scripts/package/Makefile
1060export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1061
1062vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1063
1064# Recurse until adjust_autoksyms.sh is satisfied
1065PHONY += autoksyms_recursive
1066ifdef CONFIG_TRIM_UNUSED_KSYMS
1067autoksyms_recursive: descend modules.order
1068	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1069	  "$(MAKE) -f $(srctree)/Makefile vmlinux"
1070endif
1071
1072# For the kernel to actually contain only the needed exported symbols,
1073# we have to build modules as well to determine what those symbols are.
1074# (this can be evaluated only once include/config/auto.conf has been included)
1075ifdef CONFIG_TRIM_UNUSED_KSYMS
1076  KBUILD_MODULES := 1
1077endif
1078
1079autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1080
1081$(autoksyms_h):
1082	$(Q)mkdir -p $(dir $@)
1083	$(Q)touch $@
1084
1085ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1086
1087# Final link of vmlinux with optional arch pass after final link
1088cmd_link-vmlinux =                                                 \
1089	$(CONFIG_SHELL) $< $(LD) $(KBUILD_LDFLAGS) $(LDFLAGS_vmlinux) ;    \
1090	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1091
1092vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1093	+$(call if_changed,link-vmlinux)
1094
1095targets := vmlinux
1096
1097# The actual objects are generated when descending,
1098# make sure no implicit rule kicks in
1099$(sort $(vmlinux-deps)): descend ;
1100
1101filechk_kernel.release = \
1102	echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1103
1104# Store (new) KERNELRELEASE string in include/config/kernel.release
1105include/config/kernel.release: FORCE
1106	$(call filechk,kernel.release)
1107
1108# Additional helpers built in scripts/
1109# Carefully list dependencies so we do not try to build scripts twice
1110# in parallel
1111PHONY += scripts
1112scripts: scripts_basic scripts_dtc
1113	$(Q)$(MAKE) $(build)=$(@)
1114
1115# Things we need to do before we recursively start building the kernel
1116# or the modules are listed in "prepare".
1117# A multi level approach is used. prepareN is processed before prepareN-1.
1118# archprepare is used in arch Makefiles and when processed asm symlink,
1119# version.h and scripts_basic is processed / created.
1120
1121PHONY += prepare archprepare
1122
1123archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1124	asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h
1125
1126prepare0: archprepare
1127	$(Q)$(MAKE) $(build)=scripts/mod
1128	$(Q)$(MAKE) $(build)=.
1129
1130# All the preparing..
1131prepare: prepare0 prepare-objtool
1132
1133# Support for using generic headers in asm-generic
1134asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1135
1136PHONY += asm-generic uapi-asm-generic
1137asm-generic: uapi-asm-generic
1138	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1139	generic=include/asm-generic
1140uapi-asm-generic:
1141	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1142	generic=include/uapi/asm-generic
1143
1144PHONY += prepare-objtool
1145prepare-objtool: $(objtool_target)
1146ifeq ($(SKIP_STACK_VALIDATION),1)
1147ifdef CONFIG_UNWINDER_ORC
1148	@echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1149	@false
1150else
1151	@echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
1152endif
1153endif
1154
1155# Generate some files
1156# ---------------------------------------------------------------------------
1157
1158# KERNELRELEASE can change from a few different places, meaning version.h
1159# needs to be updated, so this check is forced on all builds
1160
1161uts_len := 64
1162define filechk_utsrelease.h
1163	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1164	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1165	  exit 1;                                                         \
1166	fi;                                                               \
1167	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1168endef
1169
1170define filechk_version.h
1171	echo \#define LINUX_VERSION_CODE $(shell                         \
1172	expr $(VERSION) \* 65536 + 0$(PATCHLEVEL) \* 256 + 0$(SUBLEVEL)); \
1173	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'
1174endef
1175
1176$(version_h): FORCE
1177	$(call filechk,version.h)
1178	$(Q)rm -f $(old_version_h)
1179
1180include/generated/utsrelease.h: include/config/kernel.release FORCE
1181	$(call filechk,utsrelease.h)
1182
1183PHONY += headerdep
1184headerdep:
1185	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1186	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1187
1188# ---------------------------------------------------------------------------
1189# Kernel headers
1190
1191#Default location for installed headers
1192export INSTALL_HDR_PATH = $(objtree)/usr
1193
1194quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1195      cmd_headers_install = \
1196	mkdir -p $(INSTALL_HDR_PATH); \
1197	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1198	usr/include $(INSTALL_HDR_PATH)
1199
1200PHONY += headers_install
1201headers_install: headers
1202	$(call cmd,headers_install)
1203
1204PHONY += archheaders archscripts
1205
1206hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1207
1208PHONY += headers
1209headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1210	$(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1211	  $(error Headers not exportable for the $(SRCARCH) architecture))
1212	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1213	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1214
1215PHONY += headers_check
1216headers_check: headers
1217	$(Q)$(MAKE) $(hdr-inst)=include/uapi HDRCHECK=1
1218	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi HDRCHECK=1
1219
1220ifdef CONFIG_HEADERS_INSTALL
1221prepare: headers
1222endif
1223
1224ifdef CONFIG_HEADERS_CHECK
1225all: headers_check
1226endif
1227
1228PHONY += scripts_unifdef
1229scripts_unifdef: scripts_basic
1230	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1231
1232# ---------------------------------------------------------------------------
1233# Kernel selftest
1234
1235PHONY += kselftest
1236kselftest:
1237	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1238
1239PHONY += kselftest-clean
1240kselftest-clean:
1241	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests clean
1242
1243PHONY += kselftest-merge
1244kselftest-merge:
1245	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1246	$(Q)find $(srctree)/tools/testing/selftests -name config | \
1247		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1248	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1249
1250# ---------------------------------------------------------------------------
1251# Devicetree files
1252
1253ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1254dtstree := arch/$(SRCARCH)/boot/dts
1255endif
1256
1257ifneq ($(dtstree),)
1258
1259%.dtb: include/config/kernel.release scripts_dtc
1260	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1261
1262PHONY += dtbs dtbs_install dt_binding_check
1263dtbs dtbs_check: include/config/kernel.release scripts_dtc
1264	$(Q)$(MAKE) $(build)=$(dtstree)
1265
1266dtbs_check: export CHECK_DTBS=1
1267dtbs_check: dt_binding_check
1268
1269dtbs_install:
1270	$(Q)$(MAKE) $(dtbinst)=$(dtstree)
1271
1272ifdef CONFIG_OF_EARLY_FLATTREE
1273all: dtbs
1274endif
1275
1276endif
1277
1278PHONY += scripts_dtc
1279scripts_dtc: scripts_basic
1280	$(Q)$(MAKE) $(build)=scripts/dtc
1281
1282dt_binding_check: scripts_dtc
1283	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1284
1285# ---------------------------------------------------------------------------
1286# Modules
1287
1288ifdef CONFIG_MODULES
1289
1290# By default, build modules as well
1291
1292all: modules
1293
1294# Build modules
1295#
1296# A module can be listed more than once in obj-m resulting in
1297# duplicate lines in modules.order files.  Those are removed
1298# using awk while concatenating to the final file.
1299
1300PHONY += modules
1301modules: $(if $(KBUILD_BUILTIN),vmlinux) modules.order modules.builtin
1302	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1303	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh
1304
1305modules.order: descend
1306	$(Q)$(AWK) '!x[$$0]++' $(addsuffix /$@, $(build-dirs)) > $@
1307
1308modbuiltin-dirs := $(addprefix _modbuiltin_, $(build-dirs))
1309
1310modules.builtin: $(modbuiltin-dirs)
1311	$(Q)$(AWK) '!x[$$0]++' $(addsuffix /$@, $(build-dirs)) > $@
1312
1313PHONY += $(modbuiltin-dirs)
1314# tristate.conf is not included from this Makefile. Add it as a prerequisite
1315# here to make it self-healing in case somebody accidentally removes it.
1316$(modbuiltin-dirs): include/config/tristate.conf
1317	$(Q)$(MAKE) $(modbuiltin)=$(patsubst _modbuiltin_%,%,$@)
1318
1319# Target to prepare building external modules
1320PHONY += modules_prepare
1321modules_prepare: prepare
1322
1323# Target to install modules
1324PHONY += modules_install
1325modules_install: _modinst_ _modinst_post
1326
1327PHONY += _modinst_
1328_modinst_:
1329	@rm -rf $(MODLIB)/kernel
1330	@rm -f $(MODLIB)/source
1331	@mkdir -p $(MODLIB)/kernel
1332	@ln -s $(abspath $(srctree)) $(MODLIB)/source
1333	@if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1334		rm -f $(MODLIB)/build ; \
1335		ln -s $(CURDIR) $(MODLIB)/build ; \
1336	fi
1337	@sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1338	@sed 's:^:kernel/:' modules.builtin > $(MODLIB)/modules.builtin
1339	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1340	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1341
1342# This depmod is only for convenience to give the initial
1343# boot a modules.dep even before / is mounted read-write.  However the
1344# boot script depmod is the master version.
1345PHONY += _modinst_post
1346_modinst_post: _modinst_
1347	$(call cmd,depmod)
1348
1349ifeq ($(CONFIG_MODULE_SIG), y)
1350PHONY += modules_sign
1351modules_sign:
1352	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modsign
1353endif
1354
1355else # CONFIG_MODULES
1356
1357# Modules not configured
1358# ---------------------------------------------------------------------------
1359
1360PHONY += modules modules_install
1361modules modules_install:
1362	@echo >&2
1363	@echo >&2 "The present kernel configuration has modules disabled."
1364	@echo >&2 "Type 'make config' and enable loadable module support."
1365	@echo >&2 "Then build a kernel with module support enabled."
1366	@echo >&2
1367	@exit 1
1368
1369endif # CONFIG_MODULES
1370
1371###
1372# Cleaning is done on three levels.
1373# make clean     Delete most generated files
1374#                Leave enough to build external modules
1375# make mrproper  Delete the current configuration, and all generated files
1376# make distclean Remove editor backup files, patch leftover files and the like
1377
1378# Directories & files removed with 'make clean'
1379CLEAN_DIRS  += include/ksym
1380CLEAN_FILES += modules.builtin.modinfo
1381
1382# Directories & files removed with 'make mrproper'
1383MRPROPER_DIRS  += include/config include/generated          \
1384		  arch/$(SRCARCH)/include/generated .tmp_objdiff \
1385		  debian/ snap/ tar-install/
1386MRPROPER_FILES += .config .config.old .version \
1387		  Module.symvers \
1388		  signing_key.pem signing_key.priv signing_key.x509	\
1389		  x509.genkey extra_certificates signing_key.x509.keyid	\
1390		  signing_key.x509.signer vmlinux-gdb.py \
1391		  *.spec
1392
1393# Directories & files removed with 'make distclean'
1394DISTCLEAN_DIRS  +=
1395DISTCLEAN_FILES += tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS
1396
1397# clean - Delete most, but leave enough to build external modules
1398#
1399clean: rm-dirs  := $(CLEAN_DIRS)
1400clean: rm-files := $(CLEAN_FILES)
1401
1402PHONY += archclean vmlinuxclean
1403
1404vmlinuxclean:
1405	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1406	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1407
1408clean: archclean vmlinuxclean
1409
1410# mrproper - Delete all generated files, including .config
1411#
1412mrproper: rm-dirs  := $(wildcard $(MRPROPER_DIRS))
1413mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1414mrproper-dirs      := $(addprefix _mrproper_,scripts)
1415
1416PHONY += $(mrproper-dirs) mrproper
1417$(mrproper-dirs):
1418	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1419
1420mrproper: clean $(mrproper-dirs)
1421	$(call cmd,rmdirs)
1422	$(call cmd,rmfiles)
1423
1424# distclean
1425#
1426distclean: rm-dirs  := $(wildcard $(DISTCLEAN_DIRS))
1427distclean: rm-files := $(wildcard $(DISTCLEAN_FILES))
1428
1429PHONY += distclean
1430
1431distclean: mrproper
1432	$(call cmd,rmdirs)
1433	$(call cmd,rmfiles)
1434	@find $(srctree) $(RCS_FIND_IGNORE) \
1435		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1436		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1437		-o -name 'core' \) \
1438		-type f -print | xargs rm -f
1439
1440
1441# Packaging of the kernel to various formats
1442# ---------------------------------------------------------------------------
1443
1444%src-pkg: FORCE
1445	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1446%pkg: include/config/kernel.release FORCE
1447	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1448
1449# Brief documentation of the typical targets used
1450# ---------------------------------------------------------------------------
1451
1452boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1453boards := $(sort $(notdir $(boards)))
1454board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1455board-dirs := $(sort $(notdir $(board-dirs:/=)))
1456
1457PHONY += help
1458help:
1459	@echo  'Cleaning targets:'
1460	@echo  '  clean		  - Remove most generated files but keep the config and'
1461	@echo  '                    enough build support to build external modules'
1462	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1463	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1464	@echo  ''
1465	@echo  'Configuration targets:'
1466	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1467	@echo  ''
1468	@echo  'Other generic targets:'
1469	@echo  '  all		  - Build all targets marked with [*]'
1470	@echo  '* vmlinux	  - Build the bare kernel'
1471	@echo  '* modules	  - Build all modules'
1472	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1473	@echo  '  dir/            - Build all files in dir and below'
1474	@echo  '  dir/file.[ois]  - Build specified target only'
1475	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1476	@echo  '                    (requires compiler support for LLVM assembly generation)'
1477	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1478	@echo  '                    (requires a recent binutils and recent build (System.map))'
1479	@echo  '  dir/file.ko     - Build module including final link'
1480	@echo  '  modules_prepare - Set up for building external modules'
1481	@echo  '  tags/TAGS	  - Generate tags file for editors'
1482	@echo  '  cscope	  - Generate cscope index'
1483	@echo  '  gtags           - Generate GNU GLOBAL index'
1484	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1485	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1486	@echo  '  image_name	  - Output the image name (use with make -s)'
1487	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1488	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1489	 echo  ''
1490	@echo  'Static analysers:'
1491	@echo  '  checkstack      - Generate a list of stack hogs'
1492	@echo  '  namespacecheck  - Name space analysis on compiled kernel'
1493	@echo  '  versioncheck    - Sanity check on version.h usage'
1494	@echo  '  includecheck    - Check for duplicate included header files'
1495	@echo  '  export_report   - List the usages of all exported symbols'
1496	@echo  '  headers_check   - Sanity check on exported headers'
1497	@echo  '  headerdep       - Detect inclusion cycles in headers'
1498	@echo  '  coccicheck      - Check with Coccinelle'
1499	@echo  ''
1500	@echo  'Kernel selftest:'
1501	@echo  '  kselftest       - Build and run kernel selftest (run as root)'
1502	@echo  '                    Build, install, and boot kernel before'
1503	@echo  '                    running kselftest on it'
1504	@echo  '  kselftest-clean - Remove all generated kselftest files'
1505	@echo  '  kselftest-merge - Merge all the config dependencies of kselftest to existing'
1506	@echo  '                    .config.'
1507	@echo  ''
1508	@$(if $(dtstree), \
1509		echo 'Devicetree:'; \
1510		echo '* dtbs            - Build device tree blobs for enabled boards'; \
1511		echo '  dtbs_install    - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1512		echo '')
1513
1514	@echo 'Userspace tools targets:'
1515	@echo '  use "make tools/help"'
1516	@echo '  or  "cd tools; make help"'
1517	@echo  ''
1518	@echo  'Kernel packaging:'
1519	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1520	@echo  ''
1521	@echo  'Documentation targets:'
1522	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1523	@echo  ''
1524	@echo  'Architecture specific targets ($(SRCARCH)):'
1525	@$(if $(archhelp),$(archhelp),\
1526		echo '  No architecture specific help defined for $(SRCARCH)')
1527	@echo  ''
1528	@$(if $(boards), \
1529		$(foreach b, $(boards), \
1530		printf "  %-24s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1531		echo '')
1532	@$(if $(board-dirs), \
1533		$(foreach b, $(board-dirs), \
1534		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1535		printf "  %-16s - Show all of the above\\n" help-boards; \
1536		echo '')
1537
1538	@echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1539	@echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1540	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1541	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK (sparse by default)'
1542	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1543	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1544	@echo  '  make W=n   [targets] Enable extra gcc checks, n=1,2,3 where'
1545	@echo  '		1: warnings which may be relevant and do not occur too often'
1546	@echo  '		2: warnings which occur quite often but may still be relevant'
1547	@echo  '		3: more obscure warnings, can most likely be ignored'
1548	@echo  '		Multiple levels can be combined with W=12 or W=123'
1549	@echo  ''
1550	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1551	@echo  'For further info see the ./README file'
1552
1553
1554help-board-dirs := $(addprefix help-,$(board-dirs))
1555
1556help-boards: $(help-board-dirs)
1557
1558boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1559
1560$(help-board-dirs): help-%:
1561	@echo  'Architecture specific targets ($(SRCARCH) $*):'
1562	@$(if $(boards-per-dir), \
1563		$(foreach b, $(boards-per-dir), \
1564		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1565		echo '')
1566
1567
1568# Documentation targets
1569# ---------------------------------------------------------------------------
1570DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1571	       linkcheckdocs dochelp refcheckdocs
1572PHONY += $(DOC_TARGETS)
1573$(DOC_TARGETS):
1574	$(Q)$(MAKE) $(build)=Documentation $@
1575
1576# Misc
1577# ---------------------------------------------------------------------------
1578
1579PHONY += scripts_gdb
1580scripts_gdb: prepare0
1581	$(Q)$(MAKE) $(build)=scripts/gdb
1582	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1583
1584ifdef CONFIG_GDB_SCRIPTS
1585all: scripts_gdb
1586endif
1587
1588else # KBUILD_EXTMOD
1589
1590###
1591# External module support.
1592# When building external modules the kernel used as basis is considered
1593# read-only, and no consistency checks are made and the make
1594# system is not used on the basis kernel. If updates are required
1595# in the basis kernel ordinary make commands (without M=...) must
1596# be used.
1597#
1598# The following are the only valid targets when building external
1599# modules.
1600# make M=dir clean     Delete all automatically generated files
1601# make M=dir modules   Make all modules in specified dir
1602# make M=dir	       Same as 'make M=dir modules'
1603# make M=dir modules_install
1604#                      Install the modules built in the module directory
1605#                      Assumes install directory is already created
1606
1607# We are always building modules
1608KBUILD_MODULES := 1
1609
1610PHONY += $(objtree)/Module.symvers
1611$(objtree)/Module.symvers:
1612	@test -e $(objtree)/Module.symvers || ( \
1613	echo; \
1614	echo "  WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1615	echo "           is missing; modules will have no dependencies and modversions."; \
1616	echo )
1617
1618build-dirs := $(KBUILD_EXTMOD)
1619PHONY += modules
1620modules: descend $(objtree)/Module.symvers
1621	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1622
1623PHONY += modules_install
1624modules_install: _emodinst_ _emodinst_post
1625
1626install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1627PHONY += _emodinst_
1628_emodinst_:
1629	$(Q)mkdir -p $(MODLIB)/$(install-dir)
1630	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1631
1632PHONY += _emodinst_post
1633_emodinst_post: _emodinst_
1634	$(call cmd,depmod)
1635
1636clean-dirs := $(KBUILD_EXTMOD)
1637clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers
1638
1639PHONY += /
1640/:
1641	@echo >&2 '"$(MAKE) /" is no longer supported. Please use "$(MAKE) ./" instead.'
1642
1643PHONY += help
1644help:
1645	@echo  '  Building external modules.'
1646	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1647	@echo  ''
1648	@echo  '  modules         - default target, build the module(s)'
1649	@echo  '  modules_install - install the module'
1650	@echo  '  clean           - remove generated files in module directory only'
1651	@echo  ''
1652
1653PHONY += prepare
1654endif # KBUILD_EXTMOD
1655
1656# Handle descending into subdirectories listed in $(build-dirs)
1657# Preset locale variables to speed up the build process. Limit locale
1658# tweaks to this spot to avoid wrong language settings when running
1659# make menuconfig etc.
1660# Error messages still appears in the original language
1661PHONY += descend $(build-dirs)
1662descend: $(build-dirs)
1663$(build-dirs): prepare
1664	$(Q)$(MAKE) $(build)=$@ single-build=$(single-build) need-builtin=1 need-modorder=1
1665
1666clean-dirs := $(addprefix _clean_, $(clean-dirs))
1667PHONY += $(clean-dirs) clean
1668$(clean-dirs):
1669	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1670
1671clean: $(clean-dirs)
1672	$(call cmd,rmdirs)
1673	$(call cmd,rmfiles)
1674	@find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1675		\( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1676		-o -name '*.ko.*' \
1677		-o -name '*.dtb' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1678		-o -name '*.dwo' -o -name '*.lst' \
1679		-o -name '*.su' -o -name '*.mod' \
1680		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1681		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1682		-o -name '*.asn1.[ch]' \
1683		-o -name '*.symtypes' -o -name 'modules.order' \
1684		-o -name modules.builtin -o -name '.tmp_*.o.*' \
1685		-o -name '*.c.[012]*.*' \
1686		-o -name '*.ll' \
1687		-o -name '*.gcno' \) -type f -print | xargs rm -f
1688
1689# Generate tags for editors
1690# ---------------------------------------------------------------------------
1691quiet_cmd_tags = GEN     $@
1692      cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
1693
1694tags TAGS cscope gtags: FORCE
1695	$(call cmd,tags)
1696
1697# Scripts to check various things for consistency
1698# ---------------------------------------------------------------------------
1699
1700PHONY += includecheck versioncheck coccicheck namespacecheck export_report
1701
1702includecheck:
1703	find $(srctree)/* $(RCS_FIND_IGNORE) \
1704		-name '*.[hcS]' -type f -print | sort \
1705		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1706
1707versioncheck:
1708	find $(srctree)/* $(RCS_FIND_IGNORE) \
1709		-name '*.[hcS]' -type f -print | sort \
1710		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1711
1712coccicheck:
1713	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/$@
1714
1715namespacecheck:
1716	$(PERL) $(srctree)/scripts/namespace.pl
1717
1718export_report:
1719	$(PERL) $(srctree)/scripts/export_report.pl
1720
1721PHONY += checkstack kernelrelease kernelversion image_name
1722
1723# UML needs a little special treatment here.  It wants to use the host
1724# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1725# else wants $(ARCH), including people doing cross-builds, which means
1726# that $(SUBARCH) doesn't work here.
1727ifeq ($(ARCH), um)
1728CHECKSTACK_ARCH := $(SUBARCH)
1729else
1730CHECKSTACK_ARCH := $(ARCH)
1731endif
1732checkstack:
1733	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1734	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1735
1736kernelrelease:
1737	@echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1738
1739kernelversion:
1740	@echo $(KERNELVERSION)
1741
1742image_name:
1743	@echo $(KBUILD_IMAGE)
1744
1745# Clear a bunch of variables before executing the submake
1746
1747ifeq ($(quiet),silent_)
1748tools_silent=s
1749endif
1750
1751tools/: FORCE
1752	$(Q)mkdir -p $(objtree)/tools
1753	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1754
1755tools/%: FORCE
1756	$(Q)mkdir -p $(objtree)/tools
1757	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1758
1759# Single targets
1760# ---------------------------------------------------------------------------
1761# To build individual files in subdirectories, you can do like this:
1762#
1763#   make foo/bar/baz.s
1764#
1765# The supported suffixes for single-target are listed in 'single-targets'
1766#
1767# To build only under specific subdirectories, you can do like this:
1768#
1769#   make foo/bar/baz/
1770
1771ifdef single-build
1772
1773single-all := $(filter $(single-targets), $(MAKECMDGOALS))
1774
1775# .ko is special because modpost is needed
1776single-ko := $(sort $(filter %.ko, $(single-all)))
1777single-no-ko := $(sort $(patsubst %.ko,%.mod, $(single-all)))
1778
1779$(single-ko): single_modpost
1780	@:
1781$(single-no-ko): descend
1782	@:
1783
1784ifeq ($(KBUILD_EXTMOD),)
1785# For the single build of in-tree modules, use a temporary file to avoid
1786# the situation of modules_install installing an invalid modules.order.
1787MODORDER := .modules.tmp
1788endif
1789
1790PHONY += single_modpost
1791single_modpost: $(single-no-ko)
1792	$(Q){ $(foreach m, $(single-ko), echo $(extmod-prefix)$m;) } > $(MODORDER)
1793	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1794
1795KBUILD_MODULES := 1
1796
1797export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod-prefix), $(single-no-ko))
1798
1799single-build = $(if $(filter-out $@/, $(single-no-ko)),1)
1800
1801endif
1802
1803# FIXME Should go into a make.lib or something
1804# ===========================================================================
1805
1806quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN   $(wildcard $(rm-dirs)))
1807      cmd_rmdirs = rm -rf $(rm-dirs)
1808
1809quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1810      cmd_rmfiles = rm -f $(rm-files)
1811
1812# Run depmod only if we have System.map and depmod is executable
1813quiet_cmd_depmod = DEPMOD  $(KERNELRELEASE)
1814      cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1815                   $(KERNELRELEASE)
1816
1817# read saved command lines for existing targets
1818existing-targets := $(wildcard $(sort $(targets)))
1819
1820-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1821
1822endif # config-targets
1823endif # mixed-build
1824endif # need-sub-make
1825
1826PHONY += FORCE
1827FORCE:
1828
1829# Declare the contents of the PHONY variable as phony.  We keep that
1830# information in a variable so we can use it in if_changed and friends.
1831.PHONY: $(PHONY)
1832