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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EF2ACC433FE for ; Tue, 1 Feb 2022 14:32:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239354AbiBAOcq (ORCPT ); Tue, 1 Feb 2022 09:32:46 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54154 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239361AbiBAOcm (ORCPT ); Tue, 1 Feb 2022 09:32:42 -0500 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [IPv6:2001:4d48:ad52:32c8:5054:ff:fe00:142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F28B4C061714 for ; Tue, 1 Feb 2022 06:32:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=I18tNObjVFDm/kZz3nk5PXOupFozTlFQM8ZlXVFWPRs=; b=XrkHdF9USSifp4SbR3sZpOZ0kz Oi3rg5K3Jj5wB03eUvBmUIJ8/vXxdMtjf37JlmIjTsY9QvCIm8OGDbIXaQPu+BUQSlHjH0tRsqgZL FH2K7sOcOVSl8qx79SSqds2hpS+K6WT+8ojS25qzquvzfo2yGJG0oO6/i7RU8uKnz/lrO+HjrN76z FbIdSkNyY/G+wHjIG50uF/d4Yj7lEjZs6FiBww7q7cZnf26Afopz5cIy2krYoHsCOcxon3nSeVZ8U 02fO7PBYwYzcpz3R9eVDMJt7H73cKtAH3Lh+ne5l4GrojSutG6k8JKx3qN/fd9MGhYMKh9cEe6O5h fF6cOQfQ==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:56966) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1nEuCw-0000hf-Bi; Tue, 01 Feb 2022 14:32:34 +0000 Received: from linux by shell.armlinux.org.uk with local (Exim 4.94.2) (envelope-from ) id 1nEuCo-00028V-8b; Tue, 01 Feb 2022 14:32:26 +0000 Date: Tue, 1 Feb 2022 14:32:26 +0000 From: "Russell King (Oracle)" To: Marc Zyngier Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, Andre Przywara , Christoffer Dall , Jintack Lim , Haibo Xu , Ganapatrao Kulkarni , Chase Conklin , James Morse , Suzuki K Poulose , Alexandru Elisei , karl.heubaum@oracle.com, mihai.carabas@oracle.com, miguel.luis@oracle.com, kernel-team@android.com Subject: Re: [PATCH v6 07/64] KVM: arm64: nv: Handle HCR_EL2.NV system register traps Message-ID: References: <20220128121912.509006-1-maz@kernel.org> <20220128121912.509006-8-maz@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220128121912.509006-8-maz@kernel.org> Sender: Russell King (Oracle) Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Fri, Jan 28, 2022 at 12:18:15PM +0000, Marc Zyngier wrote: > From: Jintack Lim > > ARM v8.3 introduces a new bit in the HCR_EL2, which is the NV bit. When > this bit is set, accessing EL2 registers in EL1 traps to EL2. In > addition, executing the following instructions in EL1 will trap to EL2: > tlbi, at, eret, and msr/mrs instructions to access SP_EL1. Most of the > instructions that trap to EL2 with the NV bit were undef at EL1 prior to > ARM v8.3. The only instruction that was not undef is eret. > > This patch sets up a handler for EL2 registers and SP_EL1 register > accesses at EL1. The host hypervisor keeps those register values in > memory, and will emulate their behavior. > > This patch doesn't set the NV bit yet. It will be set in a later patch > once nested virtualization support is completed. > > Signed-off-by: Jintack Lim > [maz: EL2_REG() macros] > Signed-off-by: Marc Zyngier Reviewed-by: Russell King (Oracle) Thanks! -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!