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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 09490C433FE for ; Mon, 13 Sep 2021 14:20:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E8B4F60249 for ; Mon, 13 Sep 2021 14:20:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345942AbhIMOU1 (ORCPT ); Mon, 13 Sep 2021 10:20:27 -0400 Received: from 8bytes.org ([81.169.241.247]:56642 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343515AbhIMOPO (ORCPT ); Mon, 13 Sep 2021 10:15:14 -0400 Received: from cap.home.8bytes.org (p549ad441.dip0.t-ipconnect.de [84.154.212.65]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 91800E7C; Mon, 13 Sep 2021 16:13:56 +0200 (CEST) From: Joerg Roedel To: Paolo Bonzini Cc: Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , x86@kernel.org, Brijesh Singh , Tom Lendacky , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Joerg Roedel Subject: [PATCH v3 2/4] KVM: SVM: Add support to handle AP reset MSR protocol Date: Mon, 13 Sep 2021 16:13:43 +0200 Message-Id: <20210913141345.27175-3-joro@8bytes.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210913141345.27175-1-joro@8bytes.org> References: <20210913141345.27175-1-joro@8bytes.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Tom Lendacky Add support for AP Reset Hold being invoked using the GHCB MSR protocol, available in version 2 of the GHCB specification. Signed-off-by: Tom Lendacky Signed-off-by: Brijesh Singh Signed-off-by: Joerg Roedel --- arch/x86/include/asm/kvm_host.h | 10 ++++++- arch/x86/kvm/svm/sev.c | 48 ++++++++++++++++++++++++++------- arch/x86/kvm/x86.c | 5 +++- 3 files changed, 51 insertions(+), 12 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index f8f48a7ec577..2f84cda48cdf 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -237,6 +237,11 @@ enum x86_intercept_stage; KVM_GUESTDBG_INJECT_DB | \ KVM_GUESTDBG_BLOCKIRQ) +enum ap_reset_hold_type { + AP_RESET_HOLD_NONE, + AP_RESET_HOLD_NAE_EVENT, + AP_RESET_HOLD_MSR_PROTO, +}; #define PFERR_PRESENT_BIT 0 #define PFERR_WRITE_BIT 1 @@ -909,6 +914,8 @@ struct kvm_vcpu_arch { #if IS_ENABLED(CONFIG_HYPERV) hpa_t hv_root_tdp; #endif + + enum ap_reset_hold_type reset_hold_type; }; struct kvm_lpage_info { @@ -1675,7 +1682,8 @@ int kvm_fast_pio(struct kvm_vcpu *vcpu, int size, unsigned short port, int in); int kvm_emulate_cpuid(struct kvm_vcpu *vcpu); int kvm_emulate_halt(struct kvm_vcpu *vcpu); int kvm_vcpu_halt(struct kvm_vcpu *vcpu); -int kvm_emulate_ap_reset_hold(struct kvm_vcpu *vcpu); +int kvm_emulate_ap_reset_hold(struct kvm_vcpu *vcpu, + enum ap_reset_hold_type type); int kvm_emulate_wbinvd(struct kvm_vcpu *vcpu); void kvm_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg); diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index f368390a5563..8cd1e4ebb4a8 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -2214,6 +2214,9 @@ static int sev_es_validate_vmgexit(struct vcpu_svm *svm) void sev_es_unmap_ghcb(struct vcpu_svm *svm) { + /* Clear any indication that the vCPU is in a type of AP Reset Hold */ + svm->vcpu.arch.reset_hold_type = AP_RESET_HOLD_NONE; + if (!svm->ghcb) return; @@ -2357,6 +2360,11 @@ static u64 ghcb_msr_cpuid_resp(u64 reg, u64 value) return msr; } +static u64 ghcb_msr_ap_rst_resp(u64 value) +{ + return (u64)GHCB_MSR_AP_RESET_HOLD_RESP | (value << GHCB_DATA_LOW); +} + static int sev_handle_vmgexit_msr_protocol(struct vcpu_svm *svm) { struct vmcb_control_area *control = &svm->vmcb->control; @@ -2405,6 +2413,16 @@ static int sev_handle_vmgexit_msr_protocol(struct vcpu_svm *svm) break; } + case GHCB_MSR_AP_RESET_HOLD_REQ: + ret = kvm_emulate_ap_reset_hold(&svm->vcpu, AP_RESET_HOLD_MSR_PROTO); + + /* + * Preset the result to a non-SIPI return and then only set + * the result to non-zero when delivering a SIPI. + */ + svm->vmcb->control.ghcb_gpa = ghcb_msr_ap_rst_resp(0); + + break; case GHCB_MSR_TERM_REQ: { u64 reason_set, reason_code; @@ -2490,7 +2508,7 @@ int sev_handle_vmgexit(struct kvm_vcpu *vcpu) ret = svm_invoke_exit_handler(vcpu, SVM_EXIT_IRET); break; case SVM_VMGEXIT_AP_HLT_LOOP: - ret = kvm_emulate_ap_reset_hold(vcpu); + ret = kvm_emulate_ap_reset_hold(vcpu, AP_RESET_HOLD_NAE_EVENT); break; case SVM_VMGEXIT_AP_JUMP_TABLE: { struct kvm_sev_info *sev = &to_kvm_svm(vcpu->kvm)->sev_info; @@ -2627,13 +2645,23 @@ void sev_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector) return; } - /* - * Subsequent SIPI: Return from an AP Reset Hold VMGEXIT, where - * the guest will set the CS and RIP. Set SW_EXIT_INFO_2 to a - * non-zero value. - */ - if (!svm->ghcb) - return; - - ghcb_set_sw_exit_info_2(svm->ghcb, 1); + /* Subsequent SIPI */ + switch (vcpu->arch.reset_hold_type) { + case AP_RESET_HOLD_NAE_EVENT: + /* + * Return from an AP Reset Hold VMGEXIT, where the guest will + * set the CS and RIP. Set SW_EXIT_INFO_2 to a non-zero value. + */ + ghcb_set_sw_exit_info_2(svm->ghcb, 1); + break; + case AP_RESET_HOLD_MSR_PROTO: + /* + * Return from an AP Reset Hold VMGEXIT, where the guest will + * set the CS and RIP. Set GHCB data field to a non-zero value. + */ + svm->vmcb->control.ghcb_gpa = ghcb_msr_ap_rst_resp(1); + break; + default: + break; + } } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 28ef14155726..412a195b07af 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -8516,10 +8516,13 @@ int kvm_emulate_halt(struct kvm_vcpu *vcpu) } EXPORT_SYMBOL_GPL(kvm_emulate_halt); -int kvm_emulate_ap_reset_hold(struct kvm_vcpu *vcpu) +int kvm_emulate_ap_reset_hold(struct kvm_vcpu *vcpu, + enum ap_reset_hold_type type) { int ret = kvm_skip_emulated_instruction(vcpu); + vcpu->arch.reset_hold_type = type; + return __kvm_vcpu_halt(vcpu, KVM_MP_STATE_AP_RESET_HOLD, KVM_EXIT_AP_RESET_HOLD) && ret; } EXPORT_SYMBOL_GPL(kvm_emulate_ap_reset_hold); -- 2.33.0