2018-07-06 12:50:32

by Arnd Bergmann

[permalink] [raw]
Subject: [PATCH] ARM: module: fix modsign build error

The asm/module.h header file can not be included standalone, which
breaks the module signing code after a recent change:

In file included from kernel/module-internal.h:13,
from kernel/module_signing.c:17:
arch/arm/include/asm/module.h:37:27: error: 'struct module' declared inside parameter list will not be visible outside of this definition or declaration [-Werror]
u32 get_module_plt(struct module *mod, unsigned long loc, Elf32_Addr val);

This adds a forward declaration of struct module to make it all work.

Fixes: f314dfea16a0 ("modsign: log module name in the event of an error")
Signed-off-by: Arnd Bergmann <[email protected]>
---
I guess it would be useful if Jessica can pick this change up
in her tree that introduced the warning.
---
arch/arm/include/asm/module.h | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/arm/include/asm/module.h b/arch/arm/include/asm/module.h
index 89ad0596033a..9e81b7c498d8 100644
--- a/arch/arm/include/asm/module.h
+++ b/arch/arm/include/asm/module.h
@@ -34,6 +34,7 @@ struct mod_arch_specific {
#endif
};

+struct module;
u32 get_module_plt(struct module *mod, unsigned long loc, Elf32_Addr val);

/*
--
2.9.0



2018-07-06 13:02:56

by Russell King (Oracle)

[permalink] [raw]
Subject: Re: [PATCH] ARM: module: fix modsign build error

On Fri, Jul 06, 2018 at 02:48:47PM +0200, Arnd Bergmann wrote:
> The asm/module.h header file can not be included standalone, which
> breaks the module signing code after a recent change:
>
> In file included from kernel/module-internal.h:13,
> from kernel/module_signing.c:17:
> arch/arm/include/asm/module.h:37:27: error: 'struct module' declared inside parameter list will not be visible outside of this definition or declaration [-Werror]
> u32 get_module_plt(struct module *mod, unsigned long loc, Elf32_Addr val);
>
> This adds a forward declaration of struct module to make it all work.
>
> Fixes: f314dfea16a0 ("modsign: log module name in the event of an error")
> Signed-off-by: Arnd Bergmann <[email protected]>

We used to have a general rule that where an asm/foo.h header and
linux/foo.h header exists, and the linux/foo.h includes the asm/foo.h,
then the linux/foo.h header will be used for including in .c files
rather than the asm/ version of the same. Is there a reason why
that can't be done here?

That said, adding this is no bad thing.

Acked-by: Russell King <[email protected]>

Thanks.

> ---
> I guess it would be useful if Jessica can pick this change up
> in her tree that introduced the warning.
> ---
> arch/arm/include/asm/module.h | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm/include/asm/module.h b/arch/arm/include/asm/module.h
> index 89ad0596033a..9e81b7c498d8 100644
> --- a/arch/arm/include/asm/module.h
> +++ b/arch/arm/include/asm/module.h
> @@ -34,6 +34,7 @@ struct mod_arch_specific {
> #endif
> };
>
> +struct module;
> u32 get_module_plt(struct module *mod, unsigned long loc, Elf32_Addr val);
>
> /*
> --
> 2.9.0
>

--
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
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2018-07-09 18:36:30

by Jessica Yu

[permalink] [raw]
Subject: Re: [PATCH] ARM: module: fix modsign build error

+++ Russell King - ARM Linux [06/07/18 14:00 +0100]:
>On Fri, Jul 06, 2018 at 02:48:47PM +0200, Arnd Bergmann wrote:
>> The asm/module.h header file can not be included standalone, which
>> breaks the module signing code after a recent change:
>>
>> In file included from kernel/module-internal.h:13,
>> from kernel/module_signing.c:17:
>> arch/arm/include/asm/module.h:37:27: error: 'struct module' declared inside parameter list will not be visible outside of this definition or declaration [-Werror]
>> u32 get_module_plt(struct module *mod, unsigned long loc, Elf32_Addr val);
>>
>> This adds a forward declaration of struct module to make it all work.
>>
>> Fixes: f314dfea16a0 ("modsign: log module name in the event of an error")
>> Signed-off-by: Arnd Bergmann <[email protected]>
>
>We used to have a general rule that where an asm/foo.h header and
>linux/foo.h header exists, and the linux/foo.h includes the asm/foo.h,
>then the linux/foo.h header will be used for including in .c files
>rather than the asm/ version of the same. Is there a reason why
>that can't be done here?

Generally yes, it's just that in this case module_signing.c neither
needs nor includes linux/module.h. The needed load_info struct
definition just requires definitions for Elf_[SPE]hdr, Elf_Addr,
Elf_Sym, etc. and those are all defined in asm/module.h.

>That said, adding this is no bad thing.
>
>Acked-by: Russell King <[email protected]>
>
>Thanks.

Thanks! Queued in modules-next.

Jessica