diff mbox series

[RFC,1/2] objtool: Run objtool only if either of the config options are selected

Message ID 20240422092206.147078-1-sv@linux.ibm.com (mailing list archive)
State New, archived
Headers show
Series [RFC,1/2] objtool: Run objtool only if either of the config options are selected | expand

Commit Message

Sathvika Vasireddy April 22, 2024, 9:22 a.m. UTC
Currently, when objtool is enabled and none of the supported options
are triggered, kernel build errors out with the below error:
error: objtool: At least one command required.

To address this, ensure that objtool is run only when either of the
config options are selected.

Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
---
 scripts/Makefile.lib | 3 +++
 1 file changed, 3 insertions(+)

Comments

Masahiro Yamada April 22, 2024, 12:09 p.m. UTC | #1
On Mon, Apr 22, 2024 at 6:25 PM Sathvika Vasireddy <sv@linux.ibm.com> wrote:
>
> Currently, when objtool is enabled and none of the supported options
> are triggered, kernel build errors out with the below error:
> error: objtool: At least one command required.


Then, I think CONFIG_OBJTOOL should be disabled.


>
> To address this, ensure that objtool is run only when either of the
> config options are selected.
>
> Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
> ---
>  scripts/Makefile.lib | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
> index 3179747cbd2c..c65bb0fbd136 100644
> --- a/scripts/Makefile.lib
> +++ b/scripts/Makefile.lib
> @@ -286,7 +286,10 @@ objtool-args = $(objtool-args-y)                                   \
>
>  delay-objtool := $(or $(CONFIG_LTO_CLANG),$(CONFIG_X86_KERNEL_IBT))
>
> +ifneq ($(objtool-args-y),)
>  cmd_objtool = $(if $(objtool-enabled), ; $(objtool) $(objtool-args) $@)
> +endif
> +
>  cmd_gen_objtooldep = $(if $(objtool-enabled), { echo ; echo '$@: $$(wildcard $(objtool))' ; } >> $(dot-target).cmd)
>
>  endif # CONFIG_OBJTOOL
> --
> 2.34.1
>
Masahiro Yamada May 6, 2024, 5:39 p.m. UTC | #2
On Tue, Apr 23, 2024 at 1:19 AM Sathvika Vasireddy
<sv@linux.vnet.ibm.com> wrote:
>
> Hi Masahiro, thanks for reviewing.
>
> On 4/22/24 5:39 PM, Masahiro Yamada wrote:
>
> On Mon, Apr 22, 2024 at 6:25 PM Sathvika Vasireddy <sv@linux.ibm.com> wrote:
>
> Currently, when objtool is enabled and none of the supported options
> are triggered, kernel build errors out with the below error:
> error: objtool: At least one command required.
>
> Then, I think CONFIG_OBJTOOL should be disabled.
>
> A subsequent patch introduces --ftr-fixup as an option to objtool to do feature fixup at build-time via CONFIG_HAVE_OBJTOOL_FTR_FIXUP option. If CONFIG_OBJTOOL is not selected, then objtool cannot be used to pass --ftr-fixup option.
>
> In cases where none of the supported options (like --mcount on powerpc for example) is triggered, but still require --ftr-fixup option to be passed to objtool, we see "error: objtool: At least one command required" errors. So, to address this, run only when either of the config options are selected.
>
> Thanks,
> Sathvika



Same as my first comment.


Bad things happen because you select OBJTOOL.

Preferably, this should be a separate program
as in the first draft, but if you insist on
integrating it into objtool, I recommend keeping
CONFIG_OBJTOOL and CONFIG_HAVE_OBJTOOL_FTR_FIXUP
as separate, unlated options.


I attach a fix-up patch applicable on top of your work.
diff mbox series

Patch

diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 3179747cbd2c..c65bb0fbd136 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -286,7 +286,10 @@  objtool-args = $(objtool-args-y)					\
 
 delay-objtool := $(or $(CONFIG_LTO_CLANG),$(CONFIG_X86_KERNEL_IBT))
 
+ifneq ($(objtool-args-y),)
 cmd_objtool = $(if $(objtool-enabled), ; $(objtool) $(objtool-args) $@)
+endif
+
 cmd_gen_objtooldep = $(if $(objtool-enabled), { echo ; echo '$@: $$(wildcard $(objtool))' ; } >> $(dot-target).cmd)
 
 endif # CONFIG_OBJTOOL