Re: [PATCH v7 8/8] kbuild: rebuild multi-object modules when objtool is updated

From: Josh Poimboeuf
Date: Fri May 27 2022 - 11:51:18 EST


On Fri, May 27, 2022 at 07:01:55PM +0900, Masahiro Yamada wrote:
> When CONFIG_LTO_CLANG or CONFIG_X86_KERNEL_IBT is enabled, objtool for
> multi-object modules is postponed until the objects are linked together.
>
> Make sure to re-run objtool and re-link multi-object modules when
> objtool is updated.
>
> Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
> Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
> Acked-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
> Tested-by: Nathan Chancellor <nathan@xxxxxxxxxx>
> Reviewed-by: Nicolas Schier <n.schier@xxxxxx>
> Tested-by: Sedat Dilek <sedat.dilek@xxxxxxxxx> # LLVM-14 (x86-64)

Hi Masahiro,

Is it also possible to rebuild vmlinux.o when objtool changes, for
CONFIG_LTO_CLANG, CONFIG_X86_KERNEL_IBT, or CONFIG_NOINSTR_VALIDATION?
That doesn't seem to be happening.

--
Josh