android_kernel_msm-6.1_noth.../scripts/Makefile.modpost
Will McVicker f66a198abb ANDROID: modpost: Support relative paths for module_srcpath
If a relative path is used for EXT_MODULES and -O is defined, then we
need to set the module_srcpath as relative to $(srctree) vs $(objtree).
Refer to [1] for more details.

[1] https://lore.kernel.org/lkml/20210120193100.3414664-1-masahiroy@kernel.org/

Bug: 180027765
Signed-off-by: Will McVicker <willmcvicker@google.com>
Change-Id: I17065f2dc7d5c3297f88500390a6f45aceea7229
2021-02-12 17:19:18 -08:00

153 lines
4.9 KiB
Text

# SPDX-License-Identifier: GPL-2.0
# ===========================================================================
# Module versions
# ===========================================================================
#
# Stage one of module building created the following:
# a) The individual .o files used for the module
# b) A <module>.o file which is the .o files above linked together
# c) A <module>.mod file, listing the name of the preliminary <module>.o file,
# plus all .o files
# d) modules.order, which lists all the modules
# Stage 2 is handled by this file and does the following
# 1) Find all modules listed in modules.order
# 2) modpost is then used to
# 3) create one <module>.mod.c file pr. module
# 4) create one Module.symvers file with CRC for all exported symbols
# Step 3 is used to place certain information in the module's ELF
# section, including information such as:
# Version magic (see include/linux/vermagic.h for full details)
# - Kernel release
# - SMP is CONFIG_SMP
# - PREEMPT is CONFIG_PREEMPT[_RT]
# - GCC Version
# Module info
# - Module version (MODULE_VERSION)
# - Module alias'es (MODULE_ALIAS)
# - Module license (MODULE_LICENSE)
# - See include/linux/module.h for more details
# Step 4 is solely used to allow module versioning in external modules,
# where the CRC of each module is retrieved from the Module.symvers file.
# KBUILD_MODPOST_WARN can be set to avoid error out in case of undefined
# symbols in the final module linking stage
# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
# This is solely useful to speed up test compiles
PHONY := __modpost
__modpost:
include include/config/auto.conf
include scripts/Kbuild.include
MODPOST = scripts/mod/modpost \
$(if $(CONFIG_MODVERSIONS),-m) \
$(if $(CONFIG_MODULE_SRCVERSION_ALL),-a) \
$(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E) \
$(if $(KBUILD_MODPOST_WARN),-w) \
-o $@
ifdef MODPOST_VMLINUX
quiet_cmd_modpost = MODPOST $@
cmd_modpost = $(MODPOST) $<
vmlinux.symvers: vmlinux.o
$(call cmd,modpost)
__modpost: vmlinux.symvers
else
ifeq ($(KBUILD_EXTMOD),)
input-symdump := vmlinux.symvers
output-symdump := Module.symvers
module_srcpath := $(srctree)
else
# set src + obj - they may be used in the modules's Makefile
obj := $(KBUILD_EXTMOD)
src := $(obj)
# Include the module's Makefile to find KBUILD_EXTRA_SYMBOLS
include $(if $(wildcard $(KBUILD_EXTMOD)/Kbuild), \
$(KBUILD_EXTMOD)/Kbuild, $(KBUILD_EXTMOD)/Makefile)
# modpost option for external modules
MODPOST += -e
input-symdump := Module.symvers $(KBUILD_EXTRA_SYMBOLS)
output-symdump := $(KBUILD_EXTMOD)/Module.symvers
# Get the external module's source path. KBUILD_EXTMOD could either be an
# absolute path or relative path from $(srctree). This makes sure that we
# aren't using a relative path from a separate working directory (O= or
# KBUILD_OUTPUT) since that may not be the actual module's SCM project path. So
# check the path relative to $(srctree) first.
ifneq ($(realpath $(srctree)/$(KBUILD_EXTMOD) 2>/dev/null),)
module_srcpath := $(srctree)/$(KBUILD_EXTMOD)
else
module_srcpath := $(KBUILD_EXTMOD)
endif
endif
ifeq ($(CONFIG_MODULE_SCMVERSION),y)
# Get the SCM version of the module. Sed verifies setlocalversion returns
# a proper revision based on the SCM type, e.g. git, mercurial, or svn.
# Note: relative M= paths are not supported when building the kernel out of the
# srctree since setlocalversion won't be able to find the module srctree.
module_scmversion := $(shell $(srctree)/scripts/setlocalversion $(module_srcpath) | \
sed -n 's/.*-\(\(g\|hg\)[a-fA-F0-9]\+\(-dirty\)\?\|svn[0-9]\+\).*/\1/p')
ifneq ($(module_scmversion),)
MODPOST += -v $(module_scmversion)
endif
endif
# modpost options for modules (both in-kernel and external)
MODPOST += \
$(addprefix -i ,$(wildcard $(input-symdump))) \
$(if $(KBUILD_NSDEPS),-d $(MODULES_NSDEPS)) \
$(if $(CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS)$(KBUILD_NSDEPS),-N)
# 'make -i -k' ignores compile errors, and builds as many modules as possible.
ifneq ($(findstring i,$(filter-out --%,$(MAKEFLAGS))),)
MODPOST += -n
endif
# Clear VPATH to not search for *.symvers in $(srctree). Check only $(objtree).
VPATH :=
$(input-symdump):
@echo >&2 'WARNING: Symbol version dump "$@" is missing.'
@echo >&2 ' Modules may not have dependencies or modversions.'
# Read out modules.order to pass in modpost.
# Otherwise, allmodconfig would fail with "Argument list too long".
quiet_cmd_modpost = MODPOST $@
cmd_modpost = sed 's/ko$$/o/' $< | $(MODPOST) -T -
$(output-symdump): $(MODORDER) $(input-symdump) FORCE
$(call if_changed,modpost)
targets += $(output-symdump)
__modpost: $(output-symdump)
ifneq ($(KBUILD_MODPOST_NOFINAL),1)
$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
endif
PHONY += FORCE
FORCE:
existing-targets := $(wildcard $(sort $(targets)))
-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
endif
.PHONY: $(PHONY)