Re: [PATCH v5 3/6] x86/arch_prctl Add a new do_arch_prctl

[Andy Lutomirski <luto@amacapital.net>]

On Wed, Sep 21, 2016 at 11:58 AM, Kyle Huey <me@kylehuey.com> wrote:
> Add a new do_arch_prctl to handle arch_prctls that are not specific to 64
> bits. Call it from the syscall entry point, but not any of the other
> callsites in the kernel, which all want one of the existing 64 bit only
> arch_prctls.
>
> Signed-off-by: Kyle Huey <khuey@kylehuey.com>
> ---
>  arch/x86/include/asm/proto.h | 1 +
>  arch/x86/kernel/process.c    | 5 +++++
>  arch/x86/kernel/process_64.c | 8 +++++++-
>  3 files changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/include/asm/proto.h b/arch/x86/include/asm/proto.h
> index 95c3e51..94a57cc 100644
> --- a/arch/x86/include/asm/proto.h
> +++ b/arch/x86/include/asm/proto.h
> @@ -30,6 +30,7 @@ void x86_report_nx(void);
>
>  extern int reboot_force;
>
> +long do_arch_prctl(struct task_struct *task, int code, unsigned long arg2);
>  #ifdef CONFIG_X86_64
>  long do_arch_prctl_64(struct task_struct *task, int code, unsigned long arg2);
>  #endif
> diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
> index 62c0b0e..97aa104 100644
> --- a/arch/x86/kernel/process.c
> +++ b/arch/x86/kernel/process.c
> @@ -567,3 +567,8 @@ unsigned long get_wchan(struct task_struct *p)
>         } while (count++ < 16 && p->state != TASK_RUNNING);
>         return 0;
>  }
> +
> +long do_arch_prctl(struct task_struct *task, int code, unsigned long arg2)
> +{
> +       return -EINVAL;
> +}

This should be do_arch_prctl_common or similar to avoid confusion.

P.S. The subject should be "x86/arch_prctl: ...".