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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 D0F94C64E7C for ; Tue, 24 Nov 2020 15:51:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 92067206F7 for ; Tue, 24 Nov 2020 15:51:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="yNprGCkZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389951AbgKXPvC (ORCPT ); Tue, 24 Nov 2020 10:51:02 -0500 Received: from mail.kernel.org ([198.145.29.99]:50306 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389441AbgKXPvB (ORCPT ); Tue, 24 Nov 2020 10:51:01 -0500 Received: from localhost.localdomain (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A3779206FA; Tue, 24 Nov 2020 15:50:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1606233061; bh=iGTW5DCrEcoewVMIU6VCUDyE6/613GOz/GK75KZKNjA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=yNprGCkZci+nY/k9S7bX+CIu2pXQVSeXYPSxqj3QRWeAoQN9lE4ckpdrm55w7hAAl X4j8xbx0oENN7L45Vw1V4aw512dKvmEo4mEmj4VD4N84aHzmWrfXB5BXlYsDkusr9r tIUnKgXX3HYobLwcovBi3dn0x4bo+cScstjtIju4= From: Will Deacon To: linux-arm-kernel@lists.infradead.org Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Will Deacon , Catalin Marinas , Marc Zyngier , Greg Kroah-Hartman , Peter Zijlstra , Morten Rasmussen , Qais Yousef , Suren Baghdasaryan , Quentin Perret , Tejun Heo , Li Zefan , Johannes Weiner , Ingo Molnar , Juri Lelli , Vincent Guittot , kernel-team@android.com Subject: [PATCH v4 03/14] KVM: arm64: Kill 32-bit vCPUs on systems with mismatched EL0 support Date: Tue, 24 Nov 2020 15:50:28 +0000 Message-Id: <20201124155039.13804-4-will@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20201124155039.13804-1-will@kernel.org> References: <20201124155039.13804-1-will@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org If a vCPU is caught running 32-bit code on a system with mismatched support at EL0, then we should kill it. Acked-by: Marc Zyngier Signed-off-by: Will Deacon --- arch/arm64/kvm/arm.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 5750ec34960e..d322ac0f4a8e 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -633,6 +633,15 @@ static void check_vcpu_requests(struct kvm_vcpu *vcpu) } } +static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu) +{ + if (likely(!vcpu_mode_is_32bit(vcpu))) + return false; + + return !system_supports_32bit_el0() || + static_branch_unlikely(&arm64_mismatched_32bit_el0); +} + /** * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code * @vcpu: The VCPU pointer @@ -816,7 +825,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) * with the asymmetric AArch32 case), return to userspace with * a fatal error. */ - if (!system_supports_32bit_el0() && vcpu_mode_is_32bit(vcpu)) { + if (vcpu_mode_is_bad_32bit(vcpu)) { /* * As we have caught the guest red-handed, decide that * it isn't fit for purpose anymore by making the vcpu -- 2.29.2.454.gaff20da3a2-goog