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-rw-r--r--scripts/Makefile.modpost155
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diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost
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+# 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 per 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.
+
+PHONY := __modpost
+__modpost:
+
+include include/config/auto.conf
+include $(srctree)/scripts/Kbuild.include
+
+MODPOST = scripts/mod/modpost
+
+modpost-args = \
+ $(if $(CONFIG_MODULES),-M) \
+ $(if $(CONFIG_MODVERSIONS),-m) \
+ $(if $(CONFIG_MODULE_SRCVERSION_ALL),-a) \
+ $(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E) \
+ $(if $(KBUILD_MODPOST_WARN),-w) \
+ $(if $(KBUILD_NSDEPS),-d $(MODULES_NSDEPS)) \
+ $(if $(CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS)$(KBUILD_NSDEPS),-N) \
+ $(if $(findstring 1, $(KBUILD_EXTRA_WARN)),-W) \
+ -o $@
+
+modpost-deps := $(MODPOST)
+
+# 'make -i -k' ignores compile errors, and builds as many modules as possible.
+ifneq ($(findstring i,$(filter-out --%,$(MAKEFLAGS))),)
+modpost-args += -n
+endif
+
+# Read out modules.order to pass in modpost.
+# Otherwise, allmodconfig would fail with "Argument list too long".
+ifdef KBUILD_MODULES
+modpost-args += -T $(MODORDER)
+modpost-deps += $(MODORDER)
+endif
+
+ifeq ($(KBUILD_EXTMOD),)
+
+# Generate the list of in-tree objects in vmlinux
+# ---------------------------------------------------------------------------
+
+# This is used to retrieve symbol versions generated by genksyms.
+ifdef CONFIG_MODVERSIONS
+vmlinux.symvers Module.symvers: .vmlinux.objs
+endif
+
+# Ignore libgcc.a
+# Some architectures do '$(CC) --print-libgcc-file-name' to borrow libgcc.a
+# from the toolchain, but there is no EXPORT_SYMBOL in it.
+
+quiet_cmd_vmlinux_objs = GEN $@
+ cmd_vmlinux_objs = \
+ for f in $(real-prereqs); do \
+ case $${f} in \
+ *libgcc.a) ;; \
+ *) $(AR) t $${f} ;; \
+ esac \
+ done > $@
+
+targets += .vmlinux.objs
+.vmlinux.objs: vmlinux.a $(KBUILD_VMLINUX_LIBS) FORCE
+ $(call if_changed,vmlinux_objs)
+
+ifdef CONFIG_TRIM_UNUSED_KSYMS
+ksym-wl := $(CONFIG_UNUSED_KSYMS_WHITELIST)
+ksym-wl := $(if $(filter-out /%, $(ksym-wl)),$(srctree)/)$(ksym-wl)
+modpost-args += -t $(addprefix -u , $(ksym-wl))
+modpost-deps += $(ksym-wl)
+endif
+
+ifeq ($(wildcard vmlinux.o),)
+missing-input := vmlinux.o
+output-symdump := modules-only.symvers
+else
+modpost-args += vmlinux.o
+modpost-deps += vmlinux.o
+output-symdump := $(if $(KBUILD_MODULES), Module.symvers, vmlinux.symvers)
+endif
+
+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 $(kbuild-file)
+
+output-symdump := $(KBUILD_EXTMOD)/Module.symvers
+
+ifeq ($(wildcard Module.symvers),)
+missing-input := Module.symvers
+else
+modpost-args += -i Module.symvers
+modpost-deps += Module.symvers
+endif
+
+modpost-args += -e $(addprefix -i , $(KBUILD_EXTRA_SYMBOLS))
+
+endif # ($(KBUILD_EXTMOD),)
+
+quiet_cmd_modpost = MODPOST $@
+ cmd_modpost = \
+ $(if $(missing-input), \
+ echo >&2 "WARNING: $(missing-input) is missing."; \
+ echo >&2 " Modules may not have dependencies or modversions."; \
+ echo >&2 " You may get many unresolved symbol errors."; \
+ echo >&2 " You can set KBUILD_MODPOST_WARN=1 to turn errors into warning"; \
+ echo >&2 " if you want to proceed at your own risk.";) \
+ $(MODPOST) $(modpost-args)
+
+targets += $(output-symdump)
+$(output-symdump): $(modpost-deps) FORCE
+ $(call if_changed,modpost)
+
+__modpost: $(output-symdump)
+PHONY += FORCE
+FORCE:
+
+existing-targets := $(wildcard $(sort $(targets)))
+
+-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
+
+.PHONY: $(PHONY)