From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.mindbit.ro (xs1.mindbit.ro [80.86.107.70]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9E7EB3ACA5E; Wed, 8 Jul 2026 20:58:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=80.86.107.70 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783544299; cv=none; b=oa7FfvkRphbZDe1cxWwrAav/lgtFf9KI5FsON1GrD+9A/BWb3FmbwMI33F03Obcb7sUzDUBjNlrvuikO3Cp8Ny3GesZtTtJUYv9ETGLVJ2+CMhF9NkkUid3CvVexcEOHVP98Di8f3Er2PX+agjHMKZ7qV5KsnZpAHE4Qd8+gYv4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783544299; c=relaxed/simple; bh=KapMEa4fkNwzhFYaHcDynpkcuOR37YUwMAHpBwDRVP4=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=nBBdYt8ph8Cfst0ZXh6Tz8PWXnIPBwhZdTfs3mBVVFywpVBprdpd/30YgM5XeNIyDxf3mrc8edCvz/qiEce4UgVNW3FCm54KM95QtHgnuAffM8tuw+ePN+x710UftTJW/iWfmgU58bsn34JHhDyclEAzsnnpJRb5PJkVYJi4GtA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=rendec.net; spf=pass smtp.mailfrom=rendec.net; dkim=pass (2048-bit key) header.d=rendec.net header.i=@rendec.net header.b=ASe5j6xg; arc=none smtp.client-ip=80.86.107.70 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=rendec.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rendec.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=rendec.net header.i=@rendec.net header.b="ASe5j6xg" Received: from bat.kanata.rendec.net (unknown [24.114.111.125]) by mail.mindbit.ro (Postfix) with ESMTPSA id 16270C3449; Wed, 8 Jul 2026 23:57:54 +0300 (EEST) DKIM-Filter: OpenDKIM Filter v2.11.0 mail.mindbit.ro 16270C3449 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rendec.net; s=default; t=1783544296; bh=hJBHj3v5/Gy9cfslRHy86J9BqBTgDtn5Jmjc8wTF3Qk=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=ASe5j6xgqpQoGzd8fN2p0AV5mCM1uJJHCeUg2Rlxt6R3B/rFXg4YDm9qyballB0nF MeA/AN3+LNtRqPRnWZ4RGvlOENBWHlzAAxkuy1RqiTPYNETGIv1etVCKTLohwMPCoB NT/6RCbGnbqh9lOdElft3AHTFq8jVQMEygtI/j0tzDA/4gvnPpYZvymBxJHR3zU5cs Ryz4Il9J/Fs/gye2m6KRNK1BfV12o1cIIRYuxI4bkUCt9PsJIjMYawd5vkU/JPUcgj eyZA8hvZdnwNhc4mJqzKcQusbBCBJYXxbEKsRMMMd2jYEyC+qotSrdgXnQbdMbEvhN tyu/tFqF5098Q== Message-ID: Subject: Re: [patch 07/18] s390/syscall: Use enter_from_user_mode_randomize_stack() From: Radu Rendec To: Thomas Gleixner , LKML Cc: Peter Zijlstra , Sven Schnelle , linux-s390@vger.kernel.org, Michael Ellerman , Shrikanth Hegde , linuxppc-dev@lists.ozlabs.org, Kees Cook , Huacai Chen , loongarch@lists.linux.dev, Paul Walmsley , Palmer Dabbelt , linux-riscv@lists.infradead.org, x86@kernel.org, Mark Rutland , Jinjie Ruan , Andy Lutomirski , Oleg Nesterov , Richard Henderson , Russell King , Catalin Marinas , Guo Ren , Geert Uytterhoeven , Thomas Bogendoerfer , Helge Deller , Yoshinori Sato , Richard Weinberger , Chris Zankel , linux-arm-kernel@lists.infradead.org, linux-alpha@vger.kernel.org, linux-csky@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linux-sh@vger.kernel.org, linux-um@lists.infradead.org, Arnd Bergmann , Vineet Gupta , Will Deacon , Brian Cain , Michal Simek , Dinh Nguyen , "David S. 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) Precedence: bulk X-Mailing-List: linux-s390@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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