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Miller" , Andreas Larsson , , , , , , =?UTF-8?Q?Michal_Such=C3=A1nek?= , Jonathan Corbet , References: <20260707181957.433213175@kernel.org> <20260707190254.030598804@kernel.org> From: Jinjie Ruan In-Reply-To: <20260707190254.030598804@kernel.org> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: kwepems500002.china.huawei.com (7.221.188.17) To dggpemf500011.china.huawei.com (7.185.36.131) On 7/8/2026 3:06 AM, Thomas Gleixner wrote: > 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 > Cc: Sven Schnelle > 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); Reviewed-by: Jinjie Ruan > + > regs->psw = get_lowcore()->svc_old_psw; > regs->int_code = get_lowcore()->svc_int_code; > update_timer_sys(); >