From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Machek Subject: Re: [PATCHv3 11/11] arm64: docs: document pointer authentication Date: Sun, 22 Apr 2018 11:00:03 +0200 Message-ID: <20180422090003.GA24344@amd> References: <20180417183735.56985-1-mark.rutland@arm.com> <20180417183735.56985-12-mark.rutland@arm.com> <20180422080520.GC17875@amd> <86h8o3r5jy.wl-marc.zyngier@arm.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="jRHKVT23PllUwdXP" Return-path: Content-Disposition: inline In-Reply-To: <86h8o3r5jy.wl-marc.zyngier@arm.com> Sender: linux-kernel-owner@vger.kernel.org To: Marc Zyngier Cc: Mark Rutland , linux-arm-kernel@lists.infradead.org, arnd@arndb.de, catalin.marinas@arm.com, cdall@kernel.org, drjones@redhat.com, kvmarm@lists.cs.columbia.edu, linux-arch@vger.kernel.org, ramana.radhakrishnan@arm.com, suzuki.poulose@arm.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, awallis@codeaurora.org, kernel-hardening@lists.openwall.com List-Id: linux-arch.vger.kernel.org --jRHKVT23PllUwdXP Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sun 2018-04-22 09:47:29, Marc Zyngier wrote: > On Sun, 22 Apr 2018 09:05:21 +0100, > Pavel Machek wrote: > >=20 > > Hi! > >=20 > > > @@ -205,6 +205,14 @@ Before jumping into the kernel, the following co= nditions must be met: > > > ICC_SRE_EL2.SRE (bit 0) must be initialised to 0b0. > > > - The DT or ACPI tables must describe a GICv2 interrupt controller. > > > =20 > > > + For CPUs with pointer authentication functionality: > > > + - If EL3 is present: > > > + SCR_EL3.APK (bit 16) must be initialised to 0b1 > > > + SCR_EL3.API (bit 17) must be initialised to 0b1 > > > + - If the kernel is entered at EL1: > > > + HCR_EL2.APK (bit 40) must be initialised to 0b1 > > > + HCR_EL2.API (bit 41) must be initialised to 0b1 > > > + > >=20 > > 0b1 is quite confusing way to write 1. >=20 > Do you find 0x1 equally confusing? It is slightly better. Still I'd not use it for describing single bit. > 0bx is a pretty common way of describing bit-fields of a hardware > register. It is also consistent with the rest of this document. =2E..and inconsistent with rest of the world :-). Pavel --=20 (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo= g.html --jRHKVT23PllUwdXP Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAlrcTxMACgkQMOfwapXb+vKI0ACeMo1/1nh61yFTOI/1mDSHcvzC YrMAoIhqWJC2fBZtLjTJysk3kqkTVZC/ =h4Dt -----END PGP SIGNATURE----- --jRHKVT23PllUwdXP-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:56802 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750814AbeDVJAF (ORCPT ); Sun, 22 Apr 2018 05:00:05 -0400 Date: Sun, 22 Apr 2018 11:00:03 +0200 From: Pavel Machek Subject: Re: [PATCHv3 11/11] arm64: docs: document pointer authentication Message-ID: <20180422090003.GA24344@amd> References: <20180417183735.56985-1-mark.rutland@arm.com> <20180417183735.56985-12-mark.rutland@arm.com> <20180422080520.GC17875@amd> <86h8o3r5jy.wl-marc.zyngier@arm.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="jRHKVT23PllUwdXP" Content-Disposition: inline In-Reply-To: <86h8o3r5jy.wl-marc.zyngier@arm.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Marc Zyngier Cc: Mark Rutland , linux-arm-kernel@lists.infradead.org, arnd@arndb.de, catalin.marinas@arm.com, cdall@kernel.org, drjones@redhat.com, kvmarm@lists.cs.columbia.edu, linux-arch@vger.kernel.org, ramana.radhakrishnan@arm.com, suzuki.poulose@arm.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, awallis@codeaurora.org, kernel-hardening@lists.openwall.com Message-ID: <20180422090003.8QWy2HNNA9QbMnd3A7dWFuLEDRVJsAdARo1AKR5AkG8@z> --jRHKVT23PllUwdXP Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sun 2018-04-22 09:47:29, Marc Zyngier wrote: > On Sun, 22 Apr 2018 09:05:21 +0100, > Pavel Machek wrote: > >=20 > > Hi! > >=20 > > > @@ -205,6 +205,14 @@ Before jumping into the kernel, the following co= nditions must be met: > > > ICC_SRE_EL2.SRE (bit 0) must be initialised to 0b0. > > > - The DT or ACPI tables must describe a GICv2 interrupt controller. > > > =20 > > > + For CPUs with pointer authentication functionality: > > > + - If EL3 is present: > > > + SCR_EL3.APK (bit 16) must be initialised to 0b1 > > > + SCR_EL3.API (bit 17) must be initialised to 0b1 > > > + - If the kernel is entered at EL1: > > > + HCR_EL2.APK (bit 40) must be initialised to 0b1 > > > + HCR_EL2.API (bit 41) must be initialised to 0b1 > > > + > >=20 > > 0b1 is quite confusing way to write 1. >=20 > Do you find 0x1 equally confusing? It is slightly better. Still I'd not use it for describing single bit. > 0bx is a pretty common way of describing bit-fields of a hardware > register. It is also consistent with the rest of this document. =2E..and inconsistent with rest of the world :-). Pavel --=20 (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo= g.html --jRHKVT23PllUwdXP Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAlrcTxMACgkQMOfwapXb+vKI0ACeMo1/1nh61yFTOI/1mDSHcvzC YrMAoIhqWJC2fBZtLjTJysk3kqkTVZC/ =h4Dt -----END PGP SIGNATURE----- --jRHKVT23PllUwdXP--