Re: [PATCH v7 01/26] ptrace,x86: Make user_64bit_mode() available to 32-bit builds

From: Borislav Petkov
Date: Sun May 21 2017 - 10:20:24 EST


On Fri, May 05, 2017 at 11:16:59AM -0700, Ricardo Neri wrote:
> In its current form, user_64bit_mode() can only be used when CONFIG_X86_64
> is selected. This implies that code built with CONFIG_X86_64=n cannot use
> it. If a piece of code needs to be built for both CONFIG_X86_64=y and
> CONFIG_X86_64=n and wants to use this function, it needs to wrap it in
> an #ifdef/#endif; potentially, in multiple places.
>
> This can be easily avoided with a single #ifdef/#endif pair within
> user_64bit_mode() itself.
>
> Suggested-by: Borislav Petkov <bp@xxxxxxx>
> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
> Cc: Adam Buchbinder <adam.buchbinder@xxxxxxxxx>
> Cc: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> Cc: Lorenzo Stoakes <lstoakes@xxxxxxxxx>
> Cc: Qiaowei Ren <qiaowei.ren@xxxxxxxxx>
> Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
> Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
> Cc: Kees Cook <keescook@xxxxxxxxxxxx>
> Cc: Thomas Garnier <thgarnie@xxxxxxxxxx>
> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> Cc: Borislav Petkov <bp@xxxxxxx>
> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
> Cc: Ravi V. Shankar <ravi.v.shankar@xxxxxxxxx>
> Cc: x86@xxxxxxxxxx
> Signed-off-by: Ricardo Neri <ricardo.neri-calderon@xxxxxxxxxxxxxxx>
> ---
> arch/x86/include/asm/ptrace.h | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)

Reviewed-by: Borislav Petkov <bp@xxxxxxx>

--
Regards/Gruss,
Boris.

SUSE Linux GmbH, GF: Felix ImendÃrffer, Jane Smithard, Graham Norton, HRB 21284 (AG NÃrnberg)
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