kbuild: preprocess module linker script

There was a request to preprocess the module linker script like we
do for the vmlinux one. (https://lkml.org/lkml/2020/8/21/512)

The difference between vmlinux.lds and module.lds is that the latter
is needed for external module builds, thus must be cleaned up by
'make mrproper' instead of 'make clean'. Also, it must be created
by 'make modules_prepare'.

You cannot put it in arch/$(SRCARCH)/kernel/, which is cleaned up by
'make clean'. I moved arch/$(SRCARCH)/kernel/module.lds to
arch/$(SRCARCH)/include/asm/module.lds.h, which is included from
scripts/module.lds.S.

scripts/module.lds is fine because 'make clean' keeps all the
build artifacts under scripts/.

You can add arch-specific sections in <asm/module.lds.h>.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Jessica Yu <jeyu@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Jessica Yu <jeyu@kernel.org>
This commit is contained in:
Masahiro Yamada 2020-09-08 13:27:08 +09:00
parent 887af6d7c9
commit 596b0474d3
21 changed files with 34 additions and 23 deletions

View File

@ -505,7 +505,6 @@ KBUILD_CFLAGS_KERNEL :=
KBUILD_AFLAGS_MODULE := -DMODULE KBUILD_AFLAGS_MODULE := -DMODULE
KBUILD_CFLAGS_MODULE := -DMODULE KBUILD_CFLAGS_MODULE := -DMODULE
KBUILD_LDFLAGS_MODULE := KBUILD_LDFLAGS_MODULE :=
export KBUILD_LDS_MODULE := $(srctree)/scripts/module-common.lds
KBUILD_LDFLAGS := KBUILD_LDFLAGS :=
CLANG_FLAGS := CLANG_FLAGS :=
@ -1395,7 +1394,7 @@ endif
# using awk while concatenating to the final file. # using awk while concatenating to the final file.
PHONY += modules PHONY += modules
modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules_prepare
$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
PHONY += modules_check PHONY += modules_check
@ -1412,6 +1411,7 @@ targets += modules.order
# Target to prepare building external modules # Target to prepare building external modules
PHONY += modules_prepare PHONY += modules_prepare
modules_prepare: prepare modules_prepare: prepare
$(Q)$(MAKE) $(build)=scripts scripts/module.lds
# Target to install modules # Target to install modules
PHONY += modules_install PHONY += modules_install
@ -1743,7 +1743,9 @@ help:
@echo ' clean - remove generated files in module directory only' @echo ' clean - remove generated files in module directory only'
@echo '' @echo ''
PHONY += prepare # no-op for external module builds
PHONY += prepare modules_prepare
endif # KBUILD_EXTMOD endif # KBUILD_EXTMOD
# Single targets # Single targets
@ -1776,7 +1778,7 @@ MODORDER := .modules.tmp
endif endif
PHONY += single_modpost PHONY += single_modpost
single_modpost: $(single-no-ko) single_modpost: $(single-no-ko) modules_prepare
$(Q){ $(foreach m, $(single-ko), echo $(extmod-prefix)$m;) } > $(MODORDER) $(Q){ $(foreach m, $(single-ko), echo $(extmod-prefix)$m;) } > $(MODORDER)
$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost

View File

@ -16,10 +16,6 @@ LDFLAGS_vmlinux += --be8
KBUILD_LDFLAGS_MODULE += --be8 KBUILD_LDFLAGS_MODULE += --be8
endif endif
ifeq ($(CONFIG_ARM_MODULE_PLTS),y)
KBUILD_LDS_MODULE += $(srctree)/arch/arm/kernel/module.lds
endif
GZFLAGS :=-9 GZFLAGS :=-9
#KBUILD_CFLAGS +=-pipe #KBUILD_CFLAGS +=-pipe

View File

@ -1,5 +1,7 @@
/* SPDX-License-Identifier: GPL-2.0 */ /* SPDX-License-Identifier: GPL-2.0 */
#ifdef CONFIG_ARM_MODULE_PLTS
SECTIONS { SECTIONS {
.plt : { BYTE(0) } .plt : { BYTE(0) }
.init.plt : { BYTE(0) } .init.plt : { BYTE(0) }
} }
#endif

View File

@ -115,10 +115,6 @@ endif
CHECKFLAGS += -D__aarch64__ CHECKFLAGS += -D__aarch64__
ifeq ($(CONFIG_ARM64_MODULE_PLTS),y)
KBUILD_LDS_MODULE += $(srctree)/arch/arm64/kernel/module.lds
endif
ifeq ($(CONFIG_DYNAMIC_FTRACE_WITH_REGS),y) ifeq ($(CONFIG_DYNAMIC_FTRACE_WITH_REGS),y)
KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY
CC_FLAGS_FTRACE := -fpatchable-function-entry=2 CC_FLAGS_FTRACE := -fpatchable-function-entry=2

View File

@ -1,5 +1,7 @@
#ifdef CONFIG_ARM64_MODULE_PLTS
SECTIONS { SECTIONS {
.plt (NOLOAD) : { BYTE(0) } .plt (NOLOAD) : { BYTE(0) }
.init.plt (NOLOAD) : { BYTE(0) } .init.plt (NOLOAD) : { BYTE(0) }
.text.ftrace_trampoline (NOLOAD) : { BYTE(0) } .text.ftrace_trampoline (NOLOAD) : { BYTE(0) }
} }
#endif

View File

@ -20,7 +20,6 @@ CHECKFLAGS += -D__ia64=1 -D__ia64__=1 -D_LP64 -D__LP64__
OBJCOPYFLAGS := --strip-all OBJCOPYFLAGS := --strip-all
LDFLAGS_vmlinux := -static LDFLAGS_vmlinux := -static
KBUILD_LDS_MODULE += $(srctree)/arch/ia64/module.lds
KBUILD_AFLAGS_KERNEL := -mconstant-gp KBUILD_AFLAGS_KERNEL := -mconstant-gp
EXTRA := EXTRA :=

View File

@ -75,7 +75,6 @@ KBUILD_CPPFLAGS += -D__uClinux__
endif endif
KBUILD_LDFLAGS := -m m68kelf KBUILD_LDFLAGS := -m m68kelf
KBUILD_LDS_MODULE += $(srctree)/arch/m68k/kernel/module.lds
ifdef CONFIG_SUN3 ifdef CONFIG_SUN3
LDFLAGS_vmlinux = -N LDFLAGS_vmlinux = -N

View File

@ -65,7 +65,6 @@ UTS_MACHINE := $(subst $(space),,$(machine-y))
ifdef CONFIG_PPC32 ifdef CONFIG_PPC32
KBUILD_LDFLAGS_MODULE += arch/powerpc/lib/crtsavres.o KBUILD_LDFLAGS_MODULE += arch/powerpc/lib/crtsavres.o
else else
KBUILD_LDS_MODULE += $(srctree)/arch/powerpc/kernel/module.lds
ifeq ($(call ld-ifversion, -ge, 225000000, y),y) ifeq ($(call ld-ifversion, -ge, 225000000, y),y)
# Have the linker provide sfpr if possible. # Have the linker provide sfpr if possible.
# There is a corresponding test in arch/powerpc/lib/Makefile # There is a corresponding test in arch/powerpc/lib/Makefile

View File

@ -53,9 +53,6 @@ endif
ifeq ($(CONFIG_CMODEL_MEDANY),y) ifeq ($(CONFIG_CMODEL_MEDANY),y)
KBUILD_CFLAGS += -mcmodel=medany KBUILD_CFLAGS += -mcmodel=medany
endif endif
ifeq ($(CONFIG_MODULE_SECTIONS),y)
KBUILD_LDS_MODULE += $(srctree)/arch/riscv/kernel/module.lds
endif
ifeq ($(CONFIG_PERF_EVENTS),y) ifeq ($(CONFIG_PERF_EVENTS),y)
KBUILD_CFLAGS += -fno-omit-frame-pointer KBUILD_CFLAGS += -fno-omit-frame-pointer
endif endif

View File

@ -1,8 +1,9 @@
/* SPDX-License-Identifier: GPL-2.0 */ /* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (C) 2017 Andes Technology Corporation */ /* Copyright (C) 2017 Andes Technology Corporation */
#ifdef CONFIG_MODULE_SECTIONS
SECTIONS { SECTIONS {
.plt (NOLOAD) : { BYTE(0) } .plt (NOLOAD) : { BYTE(0) }
.got (NOLOAD) : { BYTE(0) } .got (NOLOAD) : { BYTE(0) }
.got.plt (NOLOAD) : { BYTE(0) } .got.plt (NOLOAD) : { BYTE(0) }
} }
#endif

View File

@ -16,6 +16,7 @@ generic-y += kdebug.h
generic-y += mcs_spinlock.h generic-y += mcs_spinlock.h
generic-y += mm-arch-hooks.h generic-y += mm-arch-hooks.h
generic-y += mmiowb.h generic-y += mmiowb.h
generic-y += module.lds.h
generic-y += param.h generic-y += param.h
generic-y += pci.h generic-y += pci.h
generic-y += percpu.h generic-y += percpu.h

View File

@ -40,6 +40,7 @@ mandatory-y += mmiowb.h
mandatory-y += mmu.h mandatory-y += mmu.h
mandatory-y += mmu_context.h mandatory-y += mmu_context.h
mandatory-y += module.h mandatory-y += module.h
mandatory-y += module.lds.h
mandatory-y += msi.h mandatory-y += msi.h
mandatory-y += pci.h mandatory-y += pci.h
mandatory-y += percpu.h mandatory-y += percpu.h

View File

@ -0,0 +1,10 @@
/* SPDX-License-Identifier: GPL-2.0-only */
#ifndef __ASM_GENERIC_MODULE_LDS_H
#define __ASM_GENERIC_MODULE_LDS_H
/*
* <asm/module.lds.h> can specify arch-specific sections for linking modules.
* Empty for the asm-generic header.
*/
#endif /* __ASM_GENERIC_MODULE_LDS_H */

1
scripts/.gitignore vendored
View File

@ -8,3 +8,4 @@ asn1_compiler
extract-cert extract-cert
sign-file sign-file
insert-sys-cert insert-sys-cert
/module.lds

View File

@ -29,6 +29,9 @@ endif
# The following programs are only built on demand # The following programs are only built on demand
hostprogs += unifdef hostprogs += unifdef
# The module linker script is preprocessed on demand
targets += module.lds
subdir-$(CONFIG_GCC_PLUGINS) += gcc-plugins subdir-$(CONFIG_GCC_PLUGINS) += gcc-plugins
subdir-$(CONFIG_MODVERSIONS) += genksyms subdir-$(CONFIG_MODVERSIONS) += genksyms
subdir-$(CONFIG_SECURITY_SELINUX) += selinux subdir-$(CONFIG_SECURITY_SELINUX) += selinux

View File

@ -33,11 +33,10 @@ quiet_cmd_ld_ko_o = LD [M] $@
cmd_ld_ko_o = \ cmd_ld_ko_o = \
$(LD) -r $(KBUILD_LDFLAGS) \ $(LD) -r $(KBUILD_LDFLAGS) \
$(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE) \ $(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE) \
$(addprefix -T , $(KBUILD_LDS_MODULE)) \ -T scripts/module.lds -o $@ $(filter %.o, $^); \
-o $@ $(filter %.o, $^); \
$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true) $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
$(modules): %.ko: %.o %.mod.o $(KBUILD_LDS_MODULE) FORCE $(modules): %.ko: %.o %.mod.o scripts/module.lds FORCE
+$(call if_changed,ld_ko_o) +$(call if_changed,ld_ko_o)
targets += $(modules) $(modules:.ko=.mod.o) targets += $(modules) $(modules:.ko=.mod.o)

View File

@ -24,3 +24,6 @@ SECTIONS {
__jump_table 0 : ALIGN(8) { KEEP(*(__jump_table)) } __jump_table 0 : ALIGN(8) { KEEP(*(__jump_table)) }
} }
/* bring in arch-specific sections */
#include <asm/module.lds.h>

View File

@ -55,7 +55,7 @@ deploy_kernel_headers () {
cd $srctree cd $srctree
find . arch/$SRCARCH -maxdepth 1 -name Makefile\* find . arch/$SRCARCH -maxdepth 1 -name Makefile\*
find include scripts -type f -o -type l find include scripts -type f -o -type l
find arch/$SRCARCH -name module.lds -o -name Kbuild.platforms -o -name Platform find arch/$SRCARCH -name Kbuild.platforms -o -name Platform
find $(find arch/$SRCARCH -name include -o -name scripts -type d) -type f find $(find arch/$SRCARCH -name include -o -name scripts -type d) -type f
) > debian/hdrsrcfiles ) > debian/hdrsrcfiles