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Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/gi…
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…t/mmarek/kbuild

Pull kbuild updates from Michal Marek.

Fixed up nontrivial merge conflict in Makefile as per Stephen Rothwell
and linux-next (and trivial arch/sparc/Makefile changes due to removed
sparc32 logic).

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  mips: Fix KBUILD_CPPFLAGS definition
  kbuild: fix ia64 link
  kbuild: document KBUILD_LDS, KBUILD_VMLINUX_{INIT,MAIN} and LDFLAGS_vmlinux
  kbuild: link of vmlinux moved to a script
  kbuild: refactor final link of sparc32
  kbuild: drop unused KBUILD_VMLINUX_OBJS from top-level Makefile
  kbuild: Makefile: remove unnecessary check for m68knommu ARCH
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Linus Torvalds committed May 28, 2012
2 parents 90324cc + f7fc237 commit 1347a2c
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19 changes: 19 additions & 0 deletions Documentation/kbuild/kbuild.txt
Original file line number Diff line number Diff line change
Expand Up @@ -50,6 +50,10 @@ LDFLAGS_MODULE
--------------------------------------------------
Additional options used for $(LD) when linking modules.

LDFLAGS_vmlinux
--------------------------------------------------
Additional options passed to final link of vmlinux.

KBUILD_VERBOSE
--------------------------------------------------
Set the kbuild verbosity. Can be assigned same values as "V=...".
Expand Down Expand Up @@ -214,3 +218,18 @@ KBUILD_BUILD_USER, KBUILD_BUILD_HOST
These two variables allow to override the user@host string displayed during
boot and in /proc/version. The default value is the output of the commands
whoami and host, respectively.

KBUILD_LDS
--------------------------------------------------
The linker script with full path. Assigned by the top-level Makefile.

KBUILD_VMLINUX_INIT
--------------------------------------------------
All object files for the init (first) part of vmlinux.
Files specified with KBUILD_VMLINUX_INIT are linked first.

KBUILD_VMLINUX_MAIN
--------------------------------------------------
All object files for the main part of vmlinux.
KBUILD_VMLINUX_INIT and KBUILD_VMLINUX_MAIN together specify
all the object files used to link vmlinux.
231 changes: 15 additions & 216 deletions Makefile
Original file line number Diff line number Diff line change
Expand Up @@ -231,10 +231,6 @@ endif
# Where to locate arch specific headers
hdr-arch := $(SRCARCH)

ifeq ($(ARCH),m68knommu)
hdr-arch := m68k
endif

KCONFIG_CONFIG ?= .config
export KCONFIG_CONFIG

Expand Down Expand Up @@ -341,7 +337,6 @@ AWK = awk
GENKSYMS = scripts/genksyms/genksyms
INSTALLKERNEL := installkernel
DEPMOD = /sbin/depmod
KALLSYMS = scripts/kallsyms
PERL = perl
CHECK = sparse

Expand Down Expand Up @@ -739,197 +734,21 @@ libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
libs-y2 := $(patsubst %/, %/built-in.o, $(libs-y))
libs-y := $(libs-y1) $(libs-y2)

# Build vmlinux
# ---------------------------------------------------------------------------
# vmlinux is built from the objects selected by $(vmlinux-init) and
# $(vmlinux-main). Most are built-in.o files from top-level directories
# in the kernel tree, others are specified in arch/$(ARCH)/Makefile.
# Ordering when linking is important, and $(vmlinux-init) must be first.
#
# vmlinux
# ^
# |
# +-< $(vmlinux-init)
# | +--< init/version.o + more
# |
# +--< $(vmlinux-main)
# | +--< driver/built-in.o mm/built-in.o + more
# |
# +-< kallsyms.o (see description in CONFIG_KALLSYMS section)
#
# vmlinux version (uname -v) cannot be updated during normal
# descending-into-subdirs phase since we do not yet know if we need to
# update vmlinux.
# Therefore this step is delayed until just before final link of vmlinux -
# except in the kallsyms case where it is done just before adding the
# symbols to the kernel.
#
# System.map is generated to document addresses of all kernel symbols

vmlinux-init := $(head-y) $(init-y)
vmlinux-main := $(core-y) $(libs-y) $(drivers-y) $(net-y)
vmlinux-all := $(vmlinux-init) $(vmlinux-main)
vmlinux-lds := arch/$(SRCARCH)/kernel/vmlinux.lds
export KBUILD_VMLINUX_OBJS := $(vmlinux-all)

# Rule to link vmlinux - also used during CONFIG_KALLSYMS
# May be overridden by arch/$(ARCH)/Makefile
quiet_cmd_vmlinux__ ?= LD $@
cmd_vmlinux__ ?= $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux) -o $@ \
-T $(vmlinux-lds) $(vmlinux-init) \
--start-group $(vmlinux-main) --end-group \
$(filter-out $(vmlinux-lds) $(vmlinux-init) $(vmlinux-main) vmlinux.o FORCE ,$^)

# Generate new vmlinux version
quiet_cmd_vmlinux_version = GEN .version
cmd_vmlinux_version = set -e; \
if [ ! -r .version ]; then \
rm -f .version; \
echo 1 >.version; \
else \
mv .version .old_version; \
expr 0$$(cat .old_version) + 1 >.version; \
fi; \
$(MAKE) $(build)=init

# Generate System.map
quiet_cmd_sysmap = SYSMAP
cmd_sysmap = $(CONFIG_SHELL) $(srctree)/scripts/mksysmap

# Sort exception table at build time
quiet_cmd_sortextable = SORTEX
cmd_sortextable = $(objtree)/scripts/sortextable

# Link of vmlinux
# If CONFIG_KALLSYMS is set .version is already updated
# Generate System.map and verify that the content is consistent
# Use + in front of the vmlinux_version rule to silent warning with make -j2
# First command is ':' to allow us to use + in front of the rule
define rule_vmlinux__
:
$(if $(CONFIG_KALLSYMS),,+$(call cmd,vmlinux_version))

$(call cmd,vmlinux__)
$(Q)echo 'cmd_$@ := $(cmd_vmlinux__)' > $(@D)/.$(@F).cmd

$(if $(CONFIG_BUILDTIME_EXTABLE_SORT), \
$(Q)$(if $($(quiet)cmd_sortextable), \
echo ' $($(quiet)cmd_sortextable) vmlinux' &&) \
$(cmd_sortextable) vmlinux)


$(Q)$(if $($(quiet)cmd_sysmap), \
echo ' $($(quiet)cmd_sysmap) System.map' &&) \
$(cmd_sysmap) $@ System.map; \
if [ $$? -ne 0 ]; then \
rm -f $@; \
/bin/false; \
fi;
$(verify_kallsyms)
endef


ifdef CONFIG_KALLSYMS
# Generate section listing all symbols and add it into vmlinux $(kallsyms.o)
# It's a three stage process:
# o .tmp_vmlinux1 has all symbols and sections, but __kallsyms is
# empty
# Running kallsyms on that gives us .tmp_kallsyms1.o with
# the right size - vmlinux version (uname -v) is updated during this step
# o .tmp_vmlinux2 now has a __kallsyms section of the right size,
# but due to the added section, some addresses have shifted.
# From here, we generate a correct .tmp_kallsyms2.o
# o The correct .tmp_kallsyms2.o is linked into the final vmlinux.
# o Verify that the System.map from vmlinux matches the map from
# .tmp_vmlinux2, just in case we did not generate kallsyms correctly.
# o If 'make KALLSYMS_EXTRA_PASS=1" was used, do an extra pass using
# .tmp_vmlinux3 and .tmp_kallsyms3.o. This is only meant as a
# temporary bypass to allow the kernel to be built while the
# maintainers work out what went wrong with kallsyms.

last_kallsyms := 2

ifdef KALLSYMS_EXTRA_PASS
ifneq ($(KALLSYMS_EXTRA_PASS),0)
last_kallsyms := 3
endif
endif

kallsyms.o := .tmp_kallsyms$(last_kallsyms).o

define verify_kallsyms
$(Q)$(if $($(quiet)cmd_sysmap), \
echo ' $($(quiet)cmd_sysmap) .tmp_System.map' &&) \
$(cmd_sysmap) .tmp_vmlinux$(last_kallsyms) .tmp_System.map
$(Q)cmp -s System.map .tmp_System.map || \
(echo Inconsistent kallsyms data; \
echo This is a bug - please report about it; \
echo Try "make KALLSYMS_EXTRA_PASS=1" as a workaround; \
rm .tmp_kallsyms* ; /bin/false )
endef

# Update vmlinux version before link
# Use + in front of this rule to silent warning about make -j1
# First command is ':' to allow us to use + in front of this rule
cmd_ksym_ld = $(cmd_vmlinux__)
define rule_ksym_ld
:
+$(call cmd,vmlinux_version)
$(call cmd,vmlinux__)
$(Q)echo 'cmd_$@ := $(cmd_vmlinux__)' > $(@D)/.$(@F).cmd
endef

# Generate .S file with all kernel symbols
quiet_cmd_kallsyms = KSYM $@
cmd_kallsyms = $(NM) -n $< | $(KALLSYMS) \
$(if $(CONFIG_KALLSYMS_ALL),--all-symbols) > $@
# Externally visible symbols (used by link-vmlinux.sh)
export KBUILD_VMLINUX_INIT := $(head-y) $(init-y)
export KBUILD_VMLINUX_MAIN := $(core-y) $(libs-y) $(drivers-y) $(net-y)
export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
export LDFLAGS_vmlinux

.tmp_kallsyms1.o .tmp_kallsyms2.o .tmp_kallsyms3.o: %.o: %.S scripts FORCE
$(call if_changed_dep,as_o_S)
vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN)

.tmp_kallsyms%.S: .tmp_vmlinux% $(KALLSYMS)
$(call cmd,kallsyms)
# Final link of vmlinux
cmd_link-vmlinux = $(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux)
quiet_cmd_link-vmlinux = LINK $@

# .tmp_vmlinux1 must be complete except kallsyms, so update vmlinux version
.tmp_vmlinux1: $(vmlinux-lds) $(vmlinux-all) FORCE
$(call if_changed_rule,ksym_ld)

.tmp_vmlinux2: $(vmlinux-lds) $(vmlinux-all) .tmp_kallsyms1.o FORCE
$(call if_changed,vmlinux__)

.tmp_vmlinux3: $(vmlinux-lds) $(vmlinux-all) .tmp_kallsyms2.o FORCE
$(call if_changed,vmlinux__)

# Needs to visit scripts/ before $(KALLSYMS) can be used.
$(KALLSYMS): scripts ;

# Generate some data for debugging strange kallsyms problems
debug_kallsyms: .tmp_map$(last_kallsyms)

.tmp_map%: .tmp_vmlinux% FORCE
($(OBJDUMP) -h $< | $(AWK) '/^ +[0-9]/{print $$4 " 0 " $$2}'; $(NM) $<) | sort > $@

.tmp_map3: .tmp_map2

.tmp_map2: .tmp_map1

endif # ifdef CONFIG_KALLSYMS

# Do modpost on a prelinked vmlinux. The finally linked vmlinux has
# relevant sections renamed as per the linker script.
quiet_cmd_vmlinux-modpost = LD $@
cmd_vmlinux-modpost = $(LD) $(LDFLAGS) -r -o $@ \
$(vmlinux-init) --start-group $(vmlinux-main) --end-group \
$(filter-out $(vmlinux-init) $(vmlinux-main) FORCE ,$^)
define rule_vmlinux-modpost
:
+$(call cmd,vmlinux-modpost)
$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost $@
$(Q)echo 'cmd_$@ := $(cmd_vmlinux-modpost)' > $(dot-target).cmd
endef

# vmlinux image - including updated kernel symbols
vmlinux: $(vmlinux-lds) $(vmlinux-init) $(vmlinux-main) vmlinux.o $(kallsyms.o) FORCE
# Include targets which we want to
# execute if the rest of the kernel build went well.
vmlinux: scripts/link-vmlinux.sh $(vmlinux-deps) FORCE
ifdef CONFIG_HEADERS_CHECK
$(Q)$(MAKE) -f $(srctree)/Makefile headers_check
endif
Expand All @@ -939,22 +758,11 @@ endif
ifdef CONFIG_BUILD_DOCSRC
$(Q)$(MAKE) $(build)=Documentation
endif
$(call vmlinux-modpost)
$(call if_changed_rule,vmlinux__)
$(Q)rm -f .old_version

# build vmlinux.o first to catch section mismatch errors early
ifdef CONFIG_KALLSYMS
.tmp_vmlinux1: vmlinux.o
endif

modpost-init := $(filter-out init/built-in.o, $(vmlinux-init))
vmlinux.o: $(modpost-init) $(vmlinux-main) FORCE
$(call if_changed_rule,vmlinux-modpost)
+$(call if_changed,link-vmlinux)

# The actual objects are generated when descending,
# make sure no implicit rule kicks in
$(sort $(vmlinux-init) $(vmlinux-main)) $(vmlinux-lds): $(vmlinux-dirs) ;
$(sort $(vmlinux-deps)): $(vmlinux-dirs) ;

# Handle descending into subdirectories listed in $(vmlinux-dirs)
# Preset locale variables to speed up the build process. Limit locale
Expand Down Expand Up @@ -1181,8 +989,6 @@ endif # CONFIG_MODULES

# Directories & files removed with 'make clean'
CLEAN_DIRS += $(MODVERDIR)
CLEAN_FILES += vmlinux System.map \
.tmp_kallsyms* .tmp_version .tmp_vmlinux* .tmp_System.map

# Directories & files removed with 'make mrproper'
MRPROPER_DIRS += include/config usr/include include/generated \
Expand Down Expand Up @@ -1428,6 +1234,7 @@ scripts: ;
endif # KBUILD_EXTMOD

clean: $(clean-dirs)
$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
$(call cmd,rmdirs)
$(call cmd,rmfiles)
@find $(if $(KBUILD_EXTMOD), $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
Expand Down Expand Up @@ -1568,14 +1375,6 @@ quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \
$(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*)

a_flags = -Wp,-MD,$(depfile) $(KBUILD_AFLAGS) $(AFLAGS_KERNEL) \
$(KBUILD_AFLAGS_KERNEL) \
$(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(KBUILD_CPPFLAGS) \
$(modkern_aflags) $(EXTRA_AFLAGS) $(AFLAGS_$(basetarget).o)

quiet_cmd_as_o_S = AS $@
cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<

# read all saved command lines

targets := $(wildcard $(sort $(targets)))
Expand Down
4 changes: 2 additions & 2 deletions arch/mips/Makefile
Original file line number Diff line number Diff line change
Expand Up @@ -219,8 +219,8 @@ endif

KBUILD_AFLAGS += $(cflags-y)
KBUILD_CFLAGS += $(cflags-y)
KBUILD_CPPFLAGS += -D"VMLINUX_LOAD_ADDRESS=$(load-y)"
KBUILD_CPPFLAGS += -D"DATAOFFSET=$(if $(dataoffset-y),$(dataoffset-y),0)"
KBUILD_CPPFLAGS += -DVMLINUX_LOAD_ADDRESS=$(load-y)
KBUILD_CPPFLAGS += -DDATAOFFSET=$(if $(dataoffset-y),$(dataoffset-y),0)

LDFLAGS += -m $(ld-emul)

Expand Down
11 changes: 2 additions & 9 deletions arch/um/Makefile
Original file line number Diff line number Diff line change
Expand Up @@ -121,15 +121,8 @@ LINK_WRAPS = -Wl,--wrap,malloc -Wl,--wrap,free -Wl,--wrap,calloc

LD_FLAGS_CMDLINE = $(foreach opt,$(LDFLAGS),-Wl,$(opt))

CFLAGS_vmlinux := $(LINK-y) $(LINK_WRAPS) $(LD_FLAGS_CMDLINE)
define cmd_vmlinux__
$(CC) $(CFLAGS_vmlinux) -o $@ \
-Wl,-T,$(vmlinux-lds) $(vmlinux-init) \
-Wl,--start-group $(vmlinux-main) -Wl,--end-group \
-lutil \
$(filter-out $(vmlinux-lds) $(vmlinux-init) $(vmlinux-main) vmlinux.o \
FORCE ,$^) ; rm -f linux
endef
# Used by link-vmlinux.sh which has special support for um link
export CFLAGS_vmlinux := $(LINK-y) $(LINK_WRAPS) $(LD_FLAGS_CMDLINE)

# When cleaning we don't include .config, so we don't include
# TT or skas makefiles and don't clean skas_ptregs.h.
Expand Down
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