From patchwork Wed Sep 14 08:35:00 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Will Deacon X-Patchwork-Id: 12975815 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 CBAA6ECAAD3 for ; Wed, 14 Sep 2022 08:37:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229731AbiINIh0 (ORCPT ); Wed, 14 Sep 2022 04:37:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37064 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229549AbiINIg6 (ORCPT ); Wed, 14 Sep 2022 04:36:58 -0400 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 66F0674BB0 for ; Wed, 14 Sep 2022 01:36:45 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id 173A0CE1474 for ; Wed, 14 Sep 2022 08:36:40 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id ACD03C43140; Wed, 14 Sep 2022 08:36:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1663144597; bh=MlWoZVA87h9kjzgVATfOatuufMJn9f6Ylb6LjSEGsNI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Zzq1DsNcFpuv9l/vvfs4uOEzPkpOehHeEupqvvhYZMnV32pSPMKLQl9V2lHOJclZH Tn7vL5YTssuTANKK0FXiteg/rQYdCLbtyXCmx4BmgO9R1OEC650leCyDbDbbkWBMUu 5gnIE21y9GgI6JmBLt4WoMJ5b4tloW+IsgsaDuWD7glhLPxPusRFsj/6eh9K7ur1D1 Ok1UgM/fZpylv8Tg8TdhcudMi1qzhsu42/mONPy1RW6D+Dl7jJB0hy/1//G2Rk1QdZ 3pA3nhoqrouHBCdOn8HwXnMIFiHmrxBi3Z6Z9gzRdoG+JngOdfxreXHqxrbMzm3cIx Lup7Y+6fPY6aA== From: Will Deacon To: kvmarm@lists.cs.columbia.edu Cc: Will Deacon , Sean Christopherson , Vincent Donnefort , Alexandru Elisei , Catalin Marinas , James Morse , Chao Peng , Quentin Perret , Suzuki K Poulose , Mark Rutland , Fuad Tabba , Oliver Upton , Marc Zyngier , kernel-team@android.com, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [RFC PATCH v3 25/25] KVM: arm64: Use the pKVM hyp vCPU structure in handle___kvm_vcpu_run() Date: Wed, 14 Sep 2022 09:35:00 +0100 Message-Id: <20220914083500.5118-26-will@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20220914083500.5118-1-will@kernel.org> References: <20220914083500.5118-1-will@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org As a stepping stone towards deprivileging the host's access to the guest's vCPU structures, introduce some naive flush/sync routines to copy most of the host vCPU into the hyp vCPU on vCPU run and back again on return to EL1. This allows us to run using the pKVM hyp structures when KVM is initialised in protected mode. Signed-off-by: Will Deacon --- arch/arm64/kvm/hyp/include/nvhe/pkvm.h | 4 ++ arch/arm64/kvm/hyp/nvhe/hyp-main.c | 79 +++++++++++++++++++++++++- arch/arm64/kvm/hyp/nvhe/pkvm.c | 28 +++++++++ 3 files changed, 109 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kvm/hyp/include/nvhe/pkvm.h b/arch/arm64/kvm/hyp/include/nvhe/pkvm.h index 5d456438445c..38424b98ed84 100644 --- a/arch/arm64/kvm/hyp/include/nvhe/pkvm.h +++ b/arch/arm64/kvm/hyp/include/nvhe/pkvm.h @@ -67,4 +67,8 @@ int __pkvm_init_vcpu(pkvm_handle_t handle, struct kvm_vcpu *host_vcpu, unsigned long vcpu_hva); int __pkvm_teardown_vm(pkvm_handle_t handle); +struct pkvm_hyp_vcpu *pkvm_load_hyp_vcpu(pkvm_handle_t handle, + unsigned int vcpu_idx); +void pkvm_put_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu); + #endif /* __ARM64_KVM_NVHE_PKVM_H__ */ diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c index b5f3fcfe9135..728e01d4536b 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c @@ -22,11 +22,86 @@ DEFINE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params); void __kvm_hyp_host_forward_smc(struct kvm_cpu_context *host_ctxt); +static void flush_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu) +{ + struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu; + + hyp_vcpu->vcpu.arch.ctxt = host_vcpu->arch.ctxt; + + hyp_vcpu->vcpu.arch.sve_state = kern_hyp_va(host_vcpu->arch.sve_state); + hyp_vcpu->vcpu.arch.sve_max_vl = host_vcpu->arch.sve_max_vl; + + hyp_vcpu->vcpu.arch.hw_mmu = host_vcpu->arch.hw_mmu; + + hyp_vcpu->vcpu.arch.hcr_el2 = host_vcpu->arch.hcr_el2; + hyp_vcpu->vcpu.arch.mdcr_el2 = host_vcpu->arch.mdcr_el2; + hyp_vcpu->vcpu.arch.cptr_el2 = host_vcpu->arch.cptr_el2; + + hyp_vcpu->vcpu.arch.iflags = host_vcpu->arch.iflags; + hyp_vcpu->vcpu.arch.fp_state = host_vcpu->arch.fp_state; + + hyp_vcpu->vcpu.arch.debug_ptr = kern_hyp_va(host_vcpu->arch.debug_ptr); + hyp_vcpu->vcpu.arch.host_fpsimd_state = host_vcpu->arch.host_fpsimd_state; + + hyp_vcpu->vcpu.arch.vsesr_el2 = host_vcpu->arch.vsesr_el2; + + hyp_vcpu->vcpu.arch.vgic_cpu.vgic_v3 = host_vcpu->arch.vgic_cpu.vgic_v3; +} + +static void sync_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu) +{ + struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu; + struct vgic_v3_cpu_if *hyp_cpu_if = &hyp_vcpu->vcpu.arch.vgic_cpu.vgic_v3; + struct vgic_v3_cpu_if *host_cpu_if = &host_vcpu->arch.vgic_cpu.vgic_v3; + unsigned int i; + + host_vcpu->arch.ctxt = hyp_vcpu->vcpu.arch.ctxt; + + host_vcpu->arch.hcr_el2 = hyp_vcpu->vcpu.arch.hcr_el2; + host_vcpu->arch.cptr_el2 = hyp_vcpu->vcpu.arch.cptr_el2; + + host_vcpu->arch.fault = hyp_vcpu->vcpu.arch.fault; + + host_vcpu->arch.iflags = hyp_vcpu->vcpu.arch.iflags; + host_vcpu->arch.fp_state = hyp_vcpu->vcpu.arch.fp_state; + + host_cpu_if->vgic_hcr = hyp_cpu_if->vgic_hcr; + for (i = 0; i < hyp_cpu_if->used_lrs; ++i) + host_cpu_if->vgic_lr[i] = hyp_cpu_if->vgic_lr[i]; +} + static void handle___kvm_vcpu_run(struct kvm_cpu_context *host_ctxt) { - DECLARE_REG(struct kvm_vcpu *, vcpu, host_ctxt, 1); + DECLARE_REG(struct kvm_vcpu *, host_vcpu, host_ctxt, 1); + int ret; + + host_vcpu = kern_hyp_va(host_vcpu); + + if (unlikely(is_protected_kvm_enabled())) { + struct pkvm_hyp_vcpu *hyp_vcpu; + struct kvm *host_kvm; + + host_kvm = kern_hyp_va(host_vcpu->kvm); + hyp_vcpu = pkvm_load_hyp_vcpu(host_kvm->arch.pkvm.handle, + host_vcpu->vcpu_idx); + if (!hyp_vcpu) { + ret = -EINVAL; + goto out; + } + + flush_hyp_vcpu(hyp_vcpu); + + ret = __kvm_vcpu_run(&hyp_vcpu->vcpu); + + sync_hyp_vcpu(hyp_vcpu); + pkvm_put_hyp_vcpu(hyp_vcpu); + } else { + /* The host is fully trusted, run its vCPU directly. */ + ret = __kvm_vcpu_run(host_vcpu); + } - cpu_reg(host_ctxt, 1) = __kvm_vcpu_run(kern_hyp_va(vcpu)); +out: + cpu_reg(host_ctxt, 1) = ret; } static void handle___kvm_adjust_pc(struct kvm_cpu_context *host_ctxt) diff --git a/arch/arm64/kvm/hyp/nvhe/pkvm.c b/arch/arm64/kvm/hyp/nvhe/pkvm.c index 3c9ce49dc15c..1b3f10aa4c20 100644 --- a/arch/arm64/kvm/hyp/nvhe/pkvm.c +++ b/arch/arm64/kvm/hyp/nvhe/pkvm.c @@ -241,6 +241,33 @@ static struct pkvm_hyp_vm *get_vm_by_handle(pkvm_handle_t handle) return vm_table[idx]; } +struct pkvm_hyp_vcpu *pkvm_load_hyp_vcpu(pkvm_handle_t handle, + unsigned int vcpu_idx) +{ + struct pkvm_hyp_vcpu *hyp_vcpu = NULL; + struct pkvm_hyp_vm *hyp_vm; + + hyp_spin_lock(&vm_table_lock); + hyp_vm = get_vm_by_handle(handle); + if (!hyp_vm || hyp_vm->nr_vcpus <= vcpu_idx) + goto unlock; + + hyp_vcpu = hyp_vm->vcpus[vcpu_idx]; + hyp_page_ref_inc(hyp_virt_to_page(hyp_vm)); +unlock: + hyp_spin_unlock(&vm_table_lock); + return hyp_vcpu; +} + +void pkvm_put_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu) +{ + struct pkvm_hyp_vm *hyp_vm = pkvm_hyp_vcpu_to_hyp_vm(hyp_vcpu); + + hyp_spin_lock(&vm_table_lock); + hyp_page_ref_dec(hyp_virt_to_page(hyp_vm)); + hyp_spin_unlock(&vm_table_lock); +} + static void unpin_host_vcpu(struct kvm_vcpu *host_vcpu) { if (host_vcpu) @@ -286,6 +313,7 @@ static int init_pkvm_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu, hyp_vcpu->vcpu.vcpu_idx = vcpu_idx; hyp_vcpu->vcpu.arch.hw_mmu = &hyp_vm->kvm.arch.mmu; + hyp_vcpu->vcpu.arch.cflags = READ_ONCE(host_vcpu->arch.cflags); done: if (ret) unpin_host_vcpu(host_vcpu);