Re: [patch 07/18] s390/syscall: Use enter_from_user_mode_randomize_stack()

[Sven Schnelle <svens@linux.ibm.com>]

Thomas Gleixner <tglx@kernel.org> writes:

> enter_from_user_mode_randomize_stack() replaces enter_from_user_mode() and
> the subsequent invocation of add_random_kstack_offset_irqsoff().
>
> As a bonus this avoids the overhead of get/put_cpu_var() in
> add_random_kstack_offset().
>
> No functional change.
>
> Signed-off-by: Thomas Gleixner <tglx@kernel.org>
> Cc: Sven Schnelle <svens@linux.ibm.com>
> Cc: linux-s390@vger.kernel.org
> ---
>  arch/s390/kernel/syscall.c |    4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> --- a/arch/s390/kernel/syscall.c
> +++ b/arch/s390/kernel/syscall.c
> @@ -97,8 +97,8 @@ void noinstr __do_syscall(struct pt_regs
>  {
>  	unsigned long nr;
>  
> -	enter_from_user_mode(regs);
> -	add_random_kstack_offset();
> +	enter_from_user_mode_randomize_stack(regs);
> +
>  	regs->psw = get_lowcore()->svc_old_psw;
>  	regs->int_code = get_lowcore()->svc_int_code;
>  	update_timer_sys();

Reviewed-by: Sven Schnelle <svens@linux.ibm.com>