Re: [PATCH] arm64: ftrace: fix building without CONFIG_MODULES

From: Will Deacon
Date: Fri Jun 09 2017 - 07:38:48 EST


Hi Arnd,

On Fri, Jun 09, 2017 at 12:27:06PM +0200, Arnd Bergmann wrote:
> When CONFIG_MODULES is disabled, we cannot dereference a module pointer:
>
> arch/arm64/kernel/ftrace.c: In function 'ftrace_make_call':
> arch/arm64/kernel/ftrace.c:107:36: error: dereferencing pointer to incomplete type 'struct module'
> trampoline = (unsigned long *)mod->arch.ftrace_trampoline;
>
> Also, the within_module() function is not defined:
>
> arch/arm64/kernel/ftrace.c: In function 'ftrace_make_nop':
> arch/arm64/kernel/ftrace.c:171:8: error: implicit declaration of function 'within_module'; did you mean 'init_module'? [-Werror=implicit-function-declaration]
>
> This addresses both by adding the appropriate stubs.
>
> Fixes: e71a4e1bebaf ("arm64: ftrace: add support for far branches to dynamic ftrace")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
> arch/arm64/include/asm/module.h | 6 ++++++
> arch/arm64/kernel/ftrace.c | 2 +-
> include/linux/module.h | 5 +++++
> 3 files changed, 12 insertions(+), 1 deletion(-)

I can't seem to reproduce this simply by disabling MODULES in defconfig.
Could you share your .config, please?

Will