| 1 | # SPDX-License-Identifier: GPL-2.0 |
| 2 | # =========================================================================== |
| 3 | # Module versions |
| 4 | # =========================================================================== |
| 5 | # |
| 6 | # Stage one of module building created the following: |
| 7 | # a) The individual .o files used for the module |
| 8 | # b) A <module>.o file which is the .o files above linked together |
| 9 | # c) A <module>.mod file, listing the name of the preliminary <module>.o file, |
| 10 | # plus all .o files |
| 11 | # d) modules.order, which lists all the modules |
| 12 | |
| 13 | # Stage 2 is handled by this file and does the following |
| 14 | # 1) Find all modules listed in modules.order |
| 15 | # 2) modpost is then used to |
| 16 | # 3) create one <module>.mod.c file pr. module |
| 17 | # 4) create one Module.symvers file with CRC for all exported symbols |
| 18 | |
| 19 | # Step 3 is used to place certain information in the module's ELF |
| 20 | # section, including information such as: |
| 21 | # Version magic (see include/linux/vermagic.h for full details) |
| 22 | # - Kernel release |
| 23 | # - SMP is CONFIG_SMP |
| 24 | # - PREEMPT is CONFIG_PREEMPT[_RT] |
| 25 | # - GCC Version |
| 26 | # Module info |
| 27 | # - Module version (MODULE_VERSION) |
| 28 | # - Module alias'es (MODULE_ALIAS) |
| 29 | # - Module license (MODULE_LICENSE) |
| 30 | # - See include/linux/module.h for more details |
| 31 | |
| 32 | # Step 4 is solely used to allow module versioning in external modules, |
| 33 | # where the CRC of each module is retrieved from the Module.symvers file. |
| 34 | |
| 35 | # KBUILD_MODPOST_WARN can be set to avoid error out in case of undefined |
| 36 | # symbols in the final module linking stage |
| 37 | # KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules. |
| 38 | # This is solely useful to speed up test compiles |
| 39 | |
| 40 | PHONY := __modpost |
| 41 | __modpost: |
| 42 | |
| 43 | include include/config/auto.conf |
| 44 | include scripts/Kbuild.include |
| 45 | |
| 46 | kernelsymfile := $(objtree)/Module.symvers |
| 47 | modulesymfile := $(firstword $(KBUILD_EXTMOD))/Module.symvers |
| 48 | |
| 49 | MODPOST = scripts/mod/modpost \ |
| 50 | $(if $(CONFIG_MODVERSIONS),-m) \ |
| 51 | $(if $(CONFIG_MODULE_SRCVERSION_ALL),-a) \ |
| 52 | $(if $(KBUILD_EXTMOD),-i,-o) $(kernelsymfile) \ |
| 53 | $(if $(KBUILD_EXTMOD),-I $(modulesymfile)) \ |
| 54 | $(if $(KBUILD_EXTMOD),$(addprefix -e ,$(KBUILD_EXTRA_SYMBOLS))) \ |
| 55 | $(if $(KBUILD_EXTMOD),-o $(modulesymfile)) \ |
| 56 | $(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E) \ |
| 57 | $(if $(KBUILD_MODPOST_WARN),-w) \ |
| 58 | $(if $(filter nsdeps,$(MAKECMDGOALS)),-d) |
| 59 | |
| 60 | ifdef MODPOST_VMLINUX |
| 61 | |
| 62 | quiet_cmd_modpost = MODPOST vmlinux.o |
| 63 | cmd_modpost = $(MODPOST) vmlinux.o |
| 64 | |
| 65 | __modpost: |
| 66 | $(call cmd,modpost) |
| 67 | |
| 68 | else |
| 69 | |
| 70 | # When building external modules load the Kbuild file to retrieve EXTRA_SYMBOLS info |
| 71 | ifneq ($(KBUILD_EXTMOD),) |
| 72 | |
| 73 | # set src + obj - they may be used when building the .mod.c file |
| 74 | obj := $(KBUILD_EXTMOD) |
| 75 | src := $(obj) |
| 76 | |
| 77 | # Include the module's Makefile to find KBUILD_EXTRA_SYMBOLS |
| 78 | include $(if $(wildcard $(KBUILD_EXTMOD)/Kbuild), \ |
| 79 | $(KBUILD_EXTMOD)/Kbuild, $(KBUILD_EXTMOD)/Makefile) |
| 80 | endif |
| 81 | |
| 82 | MODPOST += $(subst -i,-n,$(filter -i,$(MAKEFLAGS))) -s -T - $(wildcard vmlinux) |
| 83 | |
| 84 | # find all modules listed in modules.order |
| 85 | modules := $(sort $(shell cat $(MODORDER))) |
| 86 | |
| 87 | # Read out modules.order instead of expanding $(modules) to pass in modpost. |
| 88 | # Otherwise, allmodconfig would fail with "Argument list too long". |
| 89 | quiet_cmd_modpost = MODPOST $(words $(modules)) modules |
| 90 | cmd_modpost = sed 's/ko$$/o/' $(MODORDER) | $(MODPOST) |
| 91 | |
| 92 | __modpost: |
| 93 | @$(kecho) ' Building modules, stage 2.' |
| 94 | $(call cmd,modpost) |
| 95 | ifneq ($(KBUILD_MODPOST_NOFINAL),1) |
| 96 | $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal |
| 97 | endif |
| 98 | |
| 99 | nsdeps: __modpost |
| 100 | |
| 101 | endif |
| 102 | |
| 103 | .PHONY: $(PHONY) |