Re: [PATCH] sparc: vdso: fix build error of vdso32

From: Kees Cook
Date: Wed Nov 13 2019 - 18:59:46 EST


On Sun, Sep 22, 2019 at 08:34:36PM +0900, Masahiro Yamada wrote:
> Since commit 54b8ae66ae1a ("kbuild: change *FLAGS_<basetarget>.o to
> take the path relative to $(obj)"), sparc allmodconfig fails to build
> as follows:
>
> CC arch/sparc/vdso/vdso32/vclock_gettime.o
> unrecognized e_machine 18 arch/sparc/vdso/vdso32/vclock_gettime.o
> arch/sparc/vdso/vdso32/vclock_gettime.o: failed
>
> The cause of the breakage is that -pg flag not being dropped.
>
> The vdso32 files are located in the vdso32/ subdirectory, but I missed
> to update the Makefile.
>
> Fixes: 54b8ae66ae1a ("kbuild: change *FLAGS_<basetarget>.o to take the path relative to $(obj)")
> Reported-by: Anatoly Pugachev <matorola@xxxxxxxxx>
> Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>

I've tripped over this as well. Since no one has picked this up, can you
take it via your tree Masahiro?

Thanks!

-Kees

> ---
>
> arch/sparc/vdso/Makefile | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/arch/sparc/vdso/Makefile b/arch/sparc/vdso/Makefile
> index 324a23947585..399bc22b1cf8 100644
> --- a/arch/sparc/vdso/Makefile
> +++ b/arch/sparc/vdso/Makefile
> @@ -67,12 +67,14 @@ $(vobjs): KBUILD_CFLAGS := $(filter-out $(GCC_PLUGINS_CFLAGS) $(SPARC_REG_CFLAGS
> #
> CFLAGS_REMOVE_vdso-note.o = -pg
> CFLAGS_REMOVE_vclock_gettime.o = -pg
> +CFLAGS_REMOVE_vdso32/vdso-note.o = -pg
> +CFLAGS_REMOVE_vdso32/vclock_gettime.o = -pg
>
> $(obj)/%.so: OBJCOPYFLAGS := -S
> $(obj)/%.so: $(obj)/%.so.dbg FORCE
> $(call if_changed,objcopy)
>
> -CPPFLAGS_vdso32.lds = $(CPPFLAGS_vdso.lds)
> +CPPFLAGS_vdso32/vdso32.lds = $(CPPFLAGS_vdso.lds)
> VDSO_LDFLAGS_vdso32.lds = -m elf32_sparc -soname linux-gate.so.1
>
> #This makes sure the $(obj) subdirectory exists even though vdso32/
> --
> 2.17.1
>

--
Kees Cook