From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EE7E4C433DF for ; Mon, 15 Jun 2020 10:45:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C730020679 for ; Mon, 15 Jun 2020 10:45:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592217913; bh=NQzIZ8HPcQkoHR2c+q1ZkigBSIf8XsDf44QYuMwZ1eI=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=dtSGo67MjmxRxGQ/0DY5MGOjthP+9De3Y+yOO4+cUFhlkNGZPENU1wC0jXZKhtF43 ZzDi04VEAFYxYDhguHzHykHQn81PUxzJgAWQq26VH8CwfRkGz8tYlZw86YzHuQHk38 24szHQKu/dPHHxE493n5dqGx9yJy5qO081j24654= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729402AbgFOKpN (ORCPT ); Mon, 15 Jun 2020 06:45:13 -0400 Received: from mail.kernel.org ([198.145.29.99]:54240 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729027AbgFOKpL (ORCPT ); Mon, 15 Jun 2020 06:45:11 -0400 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 440DE20679; Mon, 15 Jun 2020 10:45:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592217910; bh=NQzIZ8HPcQkoHR2c+q1ZkigBSIf8XsDf44QYuMwZ1eI=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=1RtG08G/L03qKYK1oCOce5i21jHfrQ3NbZC8zOJcMgDMZ0czTmcyDD4bt7pC2BB3o qecG3/VcX504T1V2WOzpEUg5g2RXJmqv2ter5zGq7x6z+iBfsdH0JfYpj/dt2FmqRm v2hCvpW4bzXkjj+JNt21eLWPEaZqZnHxFtfGSm14= Received: from disco-boy.misterjones.org ([51.254.78.96] helo=www.loen.fr) by disco-boy.misterjones.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1jkmc0-0034QJ-RE; Mon, 15 Jun 2020 11:45:08 +0100 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Mon, 15 Jun 2020 11:45:08 +0100 From: Marc Zyngier To: Andrew Scull Cc: kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, James Morse , Julien Thierry , Suzuki K Poulose , kernel-team@android.com Subject: Re: [PATCH 1/4] KVM: arm64: Enable Pointer Authentication at EL2 if available In-Reply-To: <20200615084857.GD177680@google.com> References: <20200615081954.6233-1-maz@kernel.org> <20200615081954.6233-2-maz@kernel.org> <20200615084857.GD177680@google.com> User-Agent: Roundcube Webmail/1.4.4 Message-ID: <8683c038040236e1fefed067649c31d9@kernel.org> X-Sender: maz@kernel.org X-SA-Exim-Connect-IP: 51.254.78.96 X-SA-Exim-Rcpt-To: ascull@google.com, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com, kernel-team@android.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Hi Andrew, On 2020-06-15 09:48, Andrew Scull wrote: > On Mon, Jun 15, 2020 at 09:19:51AM +0100, Marc Zyngier wrote: >> While initializing EL2, switch Pointer Authentication if detected > > ^ nit: on? Yes. > >> from EL1. We use the EL1-provided keys though. >> >> Signed-off-by: Marc Zyngier >> --- >> arch/arm64/kvm/hyp-init.S | 11 +++++++++++ >> 1 file changed, 11 insertions(+) >> >> diff --git a/arch/arm64/kvm/hyp-init.S b/arch/arm64/kvm/hyp-init.S >> index 6e6ed5581eed..81732177507d 100644 >> --- a/arch/arm64/kvm/hyp-init.S >> +++ b/arch/arm64/kvm/hyp-init.S >> @@ -104,6 +104,17 @@ alternative_else_nop_endif >> */ >> mov_q x4, (SCTLR_EL2_RES1 | (SCTLR_ELx_FLAGS & ~SCTLR_ELx_A)) >> CPU_BE( orr x4, x4, #SCTLR_ELx_EE) >> +alternative_if ARM64_HAS_ADDRESS_AUTH_ARCH >> + b 1f >> +alternative_else_nop_endif >> +alternative_if_not ARM64_HAS_ADDRESS_AUTH_IMP_DEF >> + b 2f >> +alternative_else_nop_endif >> +1: >> + orr x4, x4, #(SCTLR_ELx_ENIA | SCTLR_ELx_ENIB) >> + orr x4, x4, #SCTLR_ELx_ENDA >> + orr x4, x4, #SCTLR_ELx_ENDB > > mm/proc.S builds the mask with ldr and ors it in one go, would be nice > to use the same pattern. Do you actually mean kernel/head.S, or even __ptrauth_keys_init_cpu in asm/asm_pointer_auth.h? If so, I agree that it'd be good to make it look similar by using the mov_q macro, at the expense of a spare register (which we definitely can afford here). Thanks, M. -- Jazz is not dead. It just smells funny...