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=-17.0 required=3.0 tests=BAYES_00,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 8BB51C4361B for ; Thu, 10 Dec 2020 16:22:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 65A1A22E01 for ; Thu, 10 Dec 2020 16:22:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2392258AbgLJQFw (ORCPT ); Thu, 10 Dec 2020 11:05:52 -0500 Received: from mail.kernel.org ([198.145.29.99]:34578 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392245AbgLJQFu (ORCPT ); Thu, 10 Dec 2020 11:05:50 -0500 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 7DEF723E1B; Thu, 10 Dec 2020 16:04:56 +0000 (UTC) Received: from 78.163-31-62.static.virginmediabusiness.co.uk ([62.31.163.78] helo=why.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94) (envelope-from ) id 1knOND-0008Di-CE; Thu, 10 Dec 2020 16:00:56 +0000 From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org Cc: Andre Przywara , Christoffer Dall , Jintack Lim , Alexandru Elisei , James Morse , Julien Thierry , Suzuki K Poulose , kernel-team@android.com, Jintack Lim Subject: [PATCH v3 24/66] KVM: arm64: nv: Respect the virtual HCR_EL2.NV bit setting Date: Thu, 10 Dec 2020 15:59:20 +0000 Message-Id: <20201210160002.1407373-25-maz@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201210160002.1407373-1-maz@kernel.org> References: <20201210160002.1407373-1-maz@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 62.31.163.78 X-SA-Exim-Rcpt-To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, andre.przywara@arm.com, christoffer.dall@arm.com, jintack@cs.columbia.edu, alexandru.elisei@arm.com, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com, kernel-team@android.com, jintack.lim@linaro.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Jintack Lim Forward traps due to HCR_EL2.NV bit to the virtual EL2 if they are not coming from the virtual EL2 and the virtual HCR_EL2.NV bit is set. In addition to EL2 register accesses, setting NV bit will also make EL12 register accesses trap to EL2. To emulate this for the virtual EL2, forword traps due to EL12 register accessses to the virtual EL2 if the virtual HCR_EL2.NV bit is set. This is for recursive nested virtualization. Signed-off-by: Jintack Lim [Moved code to emulate-nested.c] Signed-off-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_arm.h | 1 + arch/arm64/include/asm/kvm_nested.h | 2 ++ arch/arm64/kvm/emulate-nested.c | 27 +++++++++++++++++++++++++++ arch/arm64/kvm/handle_exit.c | 7 +++++++ arch/arm64/kvm/sys_regs.c | 24 ++++++++++++++++++++++++ 5 files changed, 61 insertions(+) diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h index 3bd29fd01d80..c18edb1b35bf 100644 --- a/arch/arm64/include/asm/kvm_arm.h +++ b/arch/arm64/include/asm/kvm_arm.h @@ -14,6 +14,7 @@ /* Hyp Configuration Register (HCR) bits */ #define HCR_ATA (UL(1) << 56) #define HCR_FWB (UL(1) << 46) +#define HCR_NV (UL(1) << 42) #define HCR_API (UL(1) << 41) #define HCR_APK (UL(1) << 40) #define HCR_TEA (UL(1) << 37) diff --git a/arch/arm64/include/asm/kvm_nested.h b/arch/arm64/include/asm/kvm_nested.h index 4c2ac9650a3e..26cba7b4d743 100644 --- a/arch/arm64/include/asm/kvm_nested.h +++ b/arch/arm64/include/asm/kvm_nested.h @@ -62,5 +62,7 @@ static inline u64 translate_cnthctl_el2_to_cntkctl_el1(u64 cnthctl) } int handle_wfx_nested(struct kvm_vcpu *vcpu, bool is_wfe); +extern bool forward_traps(struct kvm_vcpu *vcpu, u64 control_bit); +extern bool forward_nv_traps(struct kvm_vcpu *vcpu); #endif /* __ARM64_KVM_NESTED_H */ diff --git a/arch/arm64/kvm/emulate-nested.c b/arch/arm64/kvm/emulate-nested.c index ee91bcd925d8..feb9b5eded96 100644 --- a/arch/arm64/kvm/emulate-nested.c +++ b/arch/arm64/kvm/emulate-nested.c @@ -25,11 +25,38 @@ #include "trace.h" +bool forward_traps(struct kvm_vcpu *vcpu, u64 control_bit) +{ + bool control_bit_set; + + if (!nested_virt_in_use(vcpu)) + return false; + + control_bit_set = __vcpu_sys_reg(vcpu, HCR_EL2) & control_bit; + if (!vcpu_mode_el2(vcpu) && control_bit_set) { + kvm_inject_nested_sync(vcpu, kvm_vcpu_get_esr(vcpu)); + return true; + } + return false; +} + +bool forward_nv_traps(struct kvm_vcpu *vcpu) +{ + return forward_traps(vcpu, HCR_NV); +} + void kvm_emulate_nested_eret(struct kvm_vcpu *vcpu) { u64 spsr, elr, mode; bool direct_eret; + /* + * Forward this trap to the virtual EL2 if the virtual + * HCR_EL2.NV bit is set and this is coming from !EL2. + */ + if (forward_nv_traps(vcpu)) + return; + /* * Going through the whole put/load motions is a waste of time * if this is a VHE guest hypervisor returning to its own diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index 5276e8563367..0ad20457d0f1 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -64,6 +64,13 @@ static int handle_smc(struct kvm_vcpu *vcpu) { int ret; + /* + * Forward this trapped smc instruction to the virtual EL2 if + * the guest has asked for it. + */ + if (forward_traps(vcpu, HCR_TSC)) + return 1; + /* * "If an SMC instruction executed at Non-secure EL1 is * trapped to EL2 because HCR_EL2.TSC is 1, the exception is a diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 4410d399f8e2..8b0be7f0f44d 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -267,10 +267,19 @@ static u32 get_ccsidr(u32 csselr) return ccsidr; } +static bool el12_reg(struct sys_reg_params *p) +{ + /* All *_EL12 registers have Op1=5. */ + return (p->Op1 == 5); +} + static bool access_rw(struct kvm_vcpu *vcpu, struct sys_reg_params *p, const struct sys_reg_desc *r) { + if (el12_reg(p) && forward_nv_traps(vcpu)) + return false; + if (p->is_write) vcpu_write_sys_reg(vcpu, p->regval, r->reg); else @@ -294,6 +303,9 @@ static bool access_sctlr_el2(struct kvm_vcpu *vcpu, struct sys_reg_params *p, const struct sys_reg_desc *r) { + if (el12_reg(p) && forward_nv_traps(vcpu)) + return false; + if (p->is_write) { u64 val = p->regval; @@ -378,6 +390,9 @@ static bool access_vm_reg(struct kvm_vcpu *vcpu, bool was_enabled = vcpu_has_cache_enabled(vcpu); u64 val, mask, shift; + if (el12_reg(p) && forward_nv_traps(vcpu)) + return false; + /* We don't expect TRVM on the host */ BUG_ON(!vcpu_mode_el2(vcpu) && !p->is_write); @@ -1571,6 +1586,9 @@ static bool access_elr(struct kvm_vcpu *vcpu, struct sys_reg_params *p, const struct sys_reg_desc *r) { + if (el12_reg(p) && forward_nv_traps(vcpu)) + return false; + if (p->is_write) vcpu_write_sys_reg(vcpu, p->regval, ELR_EL1); else @@ -1583,6 +1601,9 @@ static bool access_spsr(struct kvm_vcpu *vcpu, struct sys_reg_params *p, const struct sys_reg_desc *r) { + if (el12_reg(p) && forward_nv_traps(vcpu)) + return false; + if (p->is_write) __vcpu_sys_reg(vcpu, SPSR_EL1) = p->regval; else @@ -1595,6 +1616,9 @@ static bool access_spsr_el2(struct kvm_vcpu *vcpu, struct sys_reg_params *p, const struct sys_reg_desc *r) { + if (el12_reg(p) && forward_nv_traps(vcpu)) + return false; + if (p->is_write) vcpu_write_sys_reg(vcpu, p->regval, SPSR_EL2); else -- 2.29.2