| Message ID | 20241121204220.2378181-37-samitolvanen@google.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Implement DWARF modversions | expand |
On Fri, Nov 22, 2024 at 5:43 AM Sami Tolvanen <samitolvanen@google.com> wrote: > > When MODVERSIONS is enabled, allow selecting gendwarfksyms as the > implementation, but default to genksyms. > > Signed-off-by: Sami Tolvanen <samitolvanen@google.com> > --- > kernel/module/Kconfig | 25 ++++++++++++++++++++++++- > scripts/Makefile | 2 +- > scripts/Makefile.build | 35 +++++++++++++++++++++++++++++------ > 3 files changed, 54 insertions(+), 8 deletions(-) > > diff --git a/kernel/module/Kconfig b/kernel/module/Kconfig > index f9e5f82fa88b..e6b2427e5c19 100644 > --- a/kernel/module/Kconfig > +++ b/kernel/module/Kconfig > @@ -169,13 +169,36 @@ config MODVERSIONS > make them incompatible with the kernel you are running. If > unsure, say N. > > +choice > + prompt "Module versioning implementation" > + depends on MODVERSIONS > + default GENKSYMS This is redundant because the first entry is the default. > + help > + Select the tool used to calculate symbol versions for modules. > + > + If unsure, select GENKSYMS. > + > +config GENKSYMS > + bool "genksyms (from source code)" > + help > + Calculate symbol versions from pre-processed source code using > + genksyms. > + > + If unsure, say Y. > + > config GENDWARFKSYMS > - bool > + bool "gendwarfksyms (from debugging information)" > depends on DEBUG_INFO > # Requires full debugging information, split DWARF not supported. > depends on !DEBUG_INFO_REDUCED && !DEBUG_INFO_SPLIT > # Requires ELF object files. > depends on !LTO > + help > + Calculate symbol versions from DWARF debugging information using > + gendwarfksyms. Requires DEBUG_INFO to be enabled. > + > + If unsure, say N. > +endchoice > > config ASM_MODVERSIONS > bool > diff --git a/scripts/Makefile b/scripts/Makefile > index d7fec46d38c0..8533f4498885 100644 > --- a/scripts/Makefile > +++ b/scripts/Makefile > @@ -53,7 +53,7 @@ hostprogs += unifdef > targets += module.lds > > subdir-$(CONFIG_GCC_PLUGINS) += gcc-plugins > -subdir-$(CONFIG_MODVERSIONS) += genksyms > +subdir-$(CONFIG_GENKSYMS) += genksyms > subdir-$(CONFIG_GENDWARFKSYMS) += gendwarfksyms > subdir-$(CONFIG_SECURITY_SELINUX) += selinux > subdir-$(CONFIG_SECURITY_IPE) += ipe > diff --git a/scripts/Makefile.build b/scripts/Makefile.build > index f41ce2131979..d6b211a7b261 100644 > --- a/scripts/Makefile.build > +++ b/scripts/Makefile.build > @@ -107,13 +107,24 @@ cmd_cpp_i_c = $(CPP) $(c_flags) -o $@ $< > $(obj)/%.i: $(obj)/%.c FORCE > $(call if_changed_dep,cpp_i_c) > > +getexportsymbols = $(NM) $@ | sed -n 's/.* __export_symbol_\(.*\)/$(1)/p' > + > +gendwarfksyms = $(objtree)/scripts/gendwarfksyms/gendwarfksyms \ > + $(if $(KBUILD_SYMTYPES), --symtypes $(@:.o=.symtypes)) \ > + $(if $(KBUILD_GENDWARFKSYMS_STABLE), --stable) > + > genksyms = $(objtree)/scripts/genksyms/genksyms \ > $(if $(KBUILD_SYMTYPES), -T $(@:.o=.symtypes)) \ > $(if $(KBUILD_PRESERVE), -p) \ > $(addprefix -r , $(wildcard $(@:.o=.symref))) > > # These mirror gensymtypes_S and co below, keep them in synch. > +ifdef CONFIG_GENDWARFKSYMS > +cmd_gensymtypes_c = $(if $(skip_gendwarfksyms),, \ > + $(call getexportsymbols,\1) | $(gendwarfksyms) $@) > +else > cmd_gensymtypes_c = $(CPP) -D__GENKSYMS__ $(c_flags) $< | $(genksyms) > +endif # CONFIG_GENDWARFKSYMS > > # LLVM assembly > # Generate .ll files from .c > @@ -279,14 +290,26 @@ $(obj)/%.ll: $(obj)/%.rs FORCE > # This is convoluted. The .S file must first be preprocessed to run guards and > # expand names, then the resulting exports must be constructed into plain > # EXPORT_SYMBOL(symbol); to build our dummy C file, and that gets preprocessed > -# to make the genksyms input. > +# to make the genksyms input or compiled into an object for gendwarfksyms. > # > # These mirror gensymtypes_c and co above, keep them in synch. > -cmd_gensymtypes_S = \ > - { echo "\#include <linux/kernel.h>" ; \ > - echo "\#include <asm/asm-prototypes.h>" ; \ > - $(NM) $@ | sed -n 's/.* __export_symbol_\(.*\)/EXPORT_SYMBOL(\1);/p' ; } | \ > - $(CPP) -D__GENKSYMS__ $(c_flags) -xc - | $(genksyms) > +getasmexports = \ > + { echo "\#include <linux/kernel.h>" ; \ > + echo "\#include <linux/string.h>" ; \ > + echo "\#include <asm/asm-prototypes.h>" ; \ > + $(call getexportsymbols,EXPORT_SYMBOL(\1);) ; } > + > +ifdef CONFIG_GENDWARFKSYMS > +cmd_gensymtypes_S = \ > + $(getasmexports) | \ > + $(CC) $(c_flags) -c -o $(@:.o=.gendwarfksyms.o) -xc -; \ > + $(call getexportsymbols,\1) | \ > + $(gendwarfksyms) $(@:.o=.gendwarfksyms.o) > +else > +cmd_gensymtypes_S = \ > + $(getasmexports) | \ > + $(CPP) -D__GENKSYMS__ $(c_flags) -xc - | $(genksyms) > +endif # CONFIG_GENDWARFKSYMS > > quiet_cmd_cpp_s_S = CPP $(quiet_modtag) $@ > cmd_cpp_s_S = $(CPP) $(a_flags) -o $@ $< > -- > 2.47.0.371.ga323438b13-goog >
diff --git a/kernel/module/Kconfig b/kernel/module/Kconfig index f9e5f82fa88b..e6b2427e5c19 100644 --- a/kernel/module/Kconfig +++ b/kernel/module/Kconfig @@ -169,13 +169,36 @@ config MODVERSIONS make them incompatible with the kernel you are running. If unsure, say N. +choice + prompt "Module versioning implementation" + depends on MODVERSIONS + default GENKSYMS + help + Select the tool used to calculate symbol versions for modules. + + If unsure, select GENKSYMS. + +config GENKSYMS + bool "genksyms (from source code)" + help + Calculate symbol versions from pre-processed source code using + genksyms. + + If unsure, say Y. + config GENDWARFKSYMS - bool + bool "gendwarfksyms (from debugging information)" depends on DEBUG_INFO # Requires full debugging information, split DWARF not supported. depends on !DEBUG_INFO_REDUCED && !DEBUG_INFO_SPLIT # Requires ELF object files. depends on !LTO + help + Calculate symbol versions from DWARF debugging information using + gendwarfksyms. Requires DEBUG_INFO to be enabled. + + If unsure, say N. +endchoice config ASM_MODVERSIONS bool diff --git a/scripts/Makefile b/scripts/Makefile index d7fec46d38c0..8533f4498885 100644 --- a/scripts/Makefile +++ b/scripts/Makefile @@ -53,7 +53,7 @@ hostprogs += unifdef targets += module.lds subdir-$(CONFIG_GCC_PLUGINS) += gcc-plugins -subdir-$(CONFIG_MODVERSIONS) += genksyms +subdir-$(CONFIG_GENKSYMS) += genksyms subdir-$(CONFIG_GENDWARFKSYMS) += gendwarfksyms subdir-$(CONFIG_SECURITY_SELINUX) += selinux subdir-$(CONFIG_SECURITY_IPE) += ipe diff --git a/scripts/Makefile.build b/scripts/Makefile.build index f41ce2131979..d6b211a7b261 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -107,13 +107,24 @@ cmd_cpp_i_c = $(CPP) $(c_flags) -o $@ $< $(obj)/%.i: $(obj)/%.c FORCE $(call if_changed_dep,cpp_i_c) +getexportsymbols = $(NM) $@ | sed -n 's/.* __export_symbol_\(.*\)/$(1)/p' + +gendwarfksyms = $(objtree)/scripts/gendwarfksyms/gendwarfksyms \ + $(if $(KBUILD_SYMTYPES), --symtypes $(@:.o=.symtypes)) \ + $(if $(KBUILD_GENDWARFKSYMS_STABLE), --stable) + genksyms = $(objtree)/scripts/genksyms/genksyms \ $(if $(KBUILD_SYMTYPES), -T $(@:.o=.symtypes)) \ $(if $(KBUILD_PRESERVE), -p) \ $(addprefix -r , $(wildcard $(@:.o=.symref))) # These mirror gensymtypes_S and co below, keep them in synch. +ifdef CONFIG_GENDWARFKSYMS +cmd_gensymtypes_c = $(if $(skip_gendwarfksyms),, \ + $(call getexportsymbols,\1) | $(gendwarfksyms) $@) +else cmd_gensymtypes_c = $(CPP) -D__GENKSYMS__ $(c_flags) $< | $(genksyms) +endif # CONFIG_GENDWARFKSYMS # LLVM assembly # Generate .ll files from .c @@ -279,14 +290,26 @@ $(obj)/%.ll: $(obj)/%.rs FORCE # This is convoluted. The .S file must first be preprocessed to run guards and # expand names, then the resulting exports must be constructed into plain # EXPORT_SYMBOL(symbol); to build our dummy C file, and that gets preprocessed -# to make the genksyms input. +# to make the genksyms input or compiled into an object for gendwarfksyms. # # These mirror gensymtypes_c and co above, keep them in synch. -cmd_gensymtypes_S = \ - { echo "\#include <linux/kernel.h>" ; \ - echo "\#include <asm/asm-prototypes.h>" ; \ - $(NM) $@ | sed -n 's/.* __export_symbol_\(.*\)/EXPORT_SYMBOL(\1);/p' ; } | \ - $(CPP) -D__GENKSYMS__ $(c_flags) -xc - | $(genksyms) +getasmexports = \ + { echo "\#include <linux/kernel.h>" ; \ + echo "\#include <linux/string.h>" ; \ + echo "\#include <asm/asm-prototypes.h>" ; \ + $(call getexportsymbols,EXPORT_SYMBOL(\1);) ; } + +ifdef CONFIG_GENDWARFKSYMS +cmd_gensymtypes_S = \ + $(getasmexports) | \ + $(CC) $(c_flags) -c -o $(@:.o=.gendwarfksyms.o) -xc -; \ + $(call getexportsymbols,\1) | \ + $(gendwarfksyms) $(@:.o=.gendwarfksyms.o) +else +cmd_gensymtypes_S = \ + $(getasmexports) | \ + $(CPP) -D__GENKSYMS__ $(c_flags) -xc - | $(genksyms) +endif # CONFIG_GENDWARFKSYMS quiet_cmd_cpp_s_S = CPP $(quiet_modtag) $@ cmd_cpp_s_S = $(CPP) $(a_flags) -o $@ $<
When MODVERSIONS is enabled, allow selecting gendwarfksyms as the implementation, but default to genksyms. Signed-off-by: Sami Tolvanen <samitolvanen@google.com> --- kernel/module/Kconfig | 25 ++++++++++++++++++++++++- scripts/Makefile | 2 +- scripts/Makefile.build | 35 +++++++++++++++++++++++++++++------ 3 files changed, 54 insertions(+), 8 deletions(-)