Re: [PATCH v6 10/20] kbuild: generate KSYMTAB entries by modpost

From: Masahiro Yamada
Date: Fri Jun 02 2023 - 09:53:07 EST


On Fri, May 26, 2023 at 2:51 AM Nick Desaulniers
<ndesaulniers@xxxxxxxxxx> wrote:
>
> On Sun, May 21, 2023 at 9:05 AM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote:
> >
> > Commit 7b4537199a4a ("kbuild: link symbol CRCs at final link, removing
> > CONFIG_MODULE_REL_CRCS") made modpost output CRCs in the same way
> > whether the EXPORT_SYMBOL() is placed in *.c or *.S.
> >
> > Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
>
> Patch LGTM, but two questions, below.
>
> > diff --git a/arch/um/os-Linux/user_syms.c b/arch/um/os-Linux/user_syms.c
> > index 9b62a9d352b3..0b3a82aedbfa 100644
> > --- a/arch/um/os-Linux/user_syms.c
> > +++ b/arch/um/os-Linux/user_syms.c
> > @@ -38,10 +38,15 @@ EXPORT_SYMBOL(vsyscall_end);
> > #endif
> >
> > /* Export symbols used by GCC for the stack protector. */
> > -extern void __stack_smash_handler(void *) __attribute__((weak));
> > +/*
> > + * REVISIT:
> > + * ARCH=um cannot enable CONFIG_STACKPROTECTOR because
> > + * 'select HAVE_STACKPROTECTOR' is missing. Is this already broken?
>
> ^ Is there something better we can do here?
>
> Maybe this code should be deleted first?

Yes, we can delete the lines first.


>
> > diff --git a/include/asm-generic/export.h b/include/asm-generic/export.h
> > index 5e4b1f2369d2..0ae9f38a904c 100644
> > --- a/include/asm-generic/export.h
> > +++ b/include/asm-generic/export.h
> > @@ -3,86 +3,12 @@
> > #define __ASM_GENERIC_EXPORT_H
> >
> > /*
> > - * This comment block is used by fixdep. Please do not remove.
>
> ^ Sounds ominous. What are the implications of removing this comment block?

The same comment existed in <linux/export.h> and <asm-generic/export.h>
because they were independent from each other.


This commit changes <asm-generic/export.h> to a wrapper of <linux/export.h>.
So, the comment in <linux/export.h> triggers rebuilding when
CONFIG_MODVERSIONS is toggled.






--
Best Regards
Masahiro Yamada