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Miller" , Andreas Larsson , linux-snps-arc@lists.infradead.org, linux-hexagon@vger.kernel.org, linux-openrisc@vger.kernel.org, sparclinux@vger.kernel.org, linux-arch@vger.kernel.org, Michal =?ISO-8859-1?Q?Such=E1nek?= , Jonathan Corbet , linux-doc@vger.kernel.org Date: Wed, 08 Jul 2026 16:57:51 -0400 In-Reply-To: <20260707190254.030598804@kernel.org> References: <20260707181957.433213175@kernel.org> <20260707190254.030598804@kernel.org> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.58.3 (3.58.3-1.fc43) X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 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 > Cc: Sven Schnelle > Cc: linux-s390@vger.kernel.org > --- > =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