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

Radu Rendec <[email protected]> Wed, 08 Jul 2026 16:57:51 -0400
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Message-ID <[email protected]> 
On Tue, 2026-07-07 at 21:06 +0200, Thomas Gleixner wrote:
> enter_from_user_mode_randomize_stack() replaces enter_from_user_mode() an=
d
> the subsequent invocation of add_random_kstack_offset_irqsoff().
>=20
> As a bonus this avoids the overhead of get/put_cpu_var() in
> add_random_kstack_offset().
>=20
> No functional change.
>=20
> Signed-off-by: Thomas Gleixner <[email protected]>
> Cc: Sven Schnelle <[email protected]>
> Cc: [email protected]
> ---
> =C2=A0arch/s390/kernel/syscall.c |=C2=A0=C2=A0=C2=A0 4 ++--
> =C2=A01 file changed, 2 insertions(+), 2 deletions(-)
>=20
> --- a/arch/s390/kernel/syscall.c
> +++ b/arch/s390/kernel/syscall.c
> @@ -97,8 +97,8 @@ void noinstr __do_syscall(struct pt_regs
> =C2=A0{
> =C2=A0	unsigned long nr;
> =C2=A0
> -	enter_from_user_mode(regs);
> -	add_random_kstack_offset();
> +	enter_from_user_mode_randomize_stack(regs);
> +
> =C2=A0	regs->psw =3D get_lowcore()->svc_old_psw;
> =C2=A0	regs->int_code =3D get_lowcore()->svc_int_code;
> =C2=A0	update_timer_sys();

Reviewed-by: Radu Rendec <[email protected]>