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,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 56051C433B4 for ; Mon, 10 May 2021 17:00:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2DADA6147E for ; Mon, 10 May 2021 17:00:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232406AbhEJRBQ (ORCPT ); Mon, 10 May 2021 13:01:16 -0400 Received: from mail.kernel.org ([198.145.29.99]:52924 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232117AbhEJRAx (ORCPT ); Mon, 10 May 2021 13:00:53 -0400 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 A225B6157E; Mon, 10 May 2021 16:59:45 +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 4.94.2) (envelope-from ) id 1lg9Fv-000Uqg-Sy; Mon, 10 May 2021 17:59:44 +0100 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 , Haibo Xu , James Morse , Suzuki K Poulose , Alexandru Elisei , kernel-team@android.com, Jintack Lim Subject: [PATCH v4 09/66] KVM: arm64: nv: Support virtual EL2 exceptions Date: Mon, 10 May 2021 17:58:23 +0100 Message-Id: <20210510165920.1913477-10-maz@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210510165920.1913477-1-maz@kernel.org> References: <20210510165920.1913477-1-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, haibo.xu@linaro.org, james.morse@arm.com, suzuki.poulose@arm.com, alexandru.elisei@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 Support injecting exceptions and performing exception returns to and from virtual EL2. This must be done entirely in software except when taking an exception from vEL0 to vEL2 when the virtual HCR_EL2.{E2H,TGE} == {1,1} (a VHE guest hypervisor). Signed-off-by: Jintack Lim Signed-off-by: Christoffer Dall [maz: switch to common exception injection framework] Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_arm.h | 17 +++ arch/arm64/include/asm/kvm_emulate.h | 10 ++ arch/arm64/kvm/Makefile | 2 +- arch/arm64/kvm/emulate-nested.c | 176 +++++++++++++++++++++++++++ arch/arm64/kvm/hyp/exception.c | 45 +++++-- arch/arm64/kvm/inject_fault.c | 63 ++++++++-- arch/arm64/kvm/trace_arm.h | 59 +++++++++ 7 files changed, 354 insertions(+), 18 deletions(-) create mode 100644 arch/arm64/kvm/emulate-nested.c diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h index 692c9049befa..e27da4165d43 100644 --- a/arch/arm64/include/asm/kvm_arm.h +++ b/arch/arm64/include/asm/kvm_arm.h @@ -335,4 +335,21 @@ #define CPACR_EL1_TTA (1 << 28) #define CPACR_EL1_DEFAULT (CPACR_EL1_FPEN | CPACR_EL1_ZEN_EL1EN) +#define kvm_mode_names \ + { PSR_MODE_EL0t, "EL0t" }, \ + { PSR_MODE_EL1t, "EL1t" }, \ + { PSR_MODE_EL1h, "EL1h" }, \ + { PSR_MODE_EL2t, "EL2t" }, \ + { PSR_MODE_EL2h, "EL2h" }, \ + { PSR_MODE_EL3t, "EL3t" }, \ + { PSR_MODE_EL3h, "EL3h" }, \ + { PSR_AA32_MODE_USR, "32-bit USR" }, \ + { PSR_AA32_MODE_FIQ, "32-bit FIQ" }, \ + { PSR_AA32_MODE_IRQ, "32-bit IRQ" }, \ + { PSR_AA32_MODE_SVC, "32-bit SVC" }, \ + { PSR_AA32_MODE_ABT, "32-bit ABT" }, \ + { PSR_AA32_MODE_HYP, "32-bit HYP" }, \ + { PSR_AA32_MODE_UND, "32-bit UND" }, \ + { PSR_AA32_MODE_SYS, "32-bit SYS" } + #endif /* __ARM64_KVM_ARM_H__ */ diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h index 706ef06c5f2b..1c10fbe7d1c3 100644 --- a/arch/arm64/include/asm/kvm_emulate.h +++ b/arch/arm64/include/asm/kvm_emulate.h @@ -33,6 +33,12 @@ enum exception_type { except_type_serror = 0x180, }; +#define kvm_exception_type_names \ + { except_type_sync, "SYNC" }, \ + { except_type_irq, "IRQ" }, \ + { except_type_fiq, "FIQ" }, \ + { except_type_serror, "SERROR" } + bool kvm_condition_valid32(const struct kvm_vcpu *vcpu); void kvm_skip_instr32(struct kvm_vcpu *vcpu); @@ -41,6 +47,10 @@ void kvm_inject_vabt(struct kvm_vcpu *vcpu); void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr); void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr); +void kvm_emulate_nested_eret(struct kvm_vcpu *vcpu); +int kvm_inject_nested_sync(struct kvm_vcpu *vcpu, u64 esr_el2); +int kvm_inject_nested_irq(struct kvm_vcpu *vcpu); + static __always_inline bool vcpu_el1_is_32bit(struct kvm_vcpu *vcpu) { return !(vcpu->arch.hcr_el2 & HCR_RW); diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index 589921392cb1..ebf6ddb3cd77 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -16,7 +16,7 @@ kvm-y := $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o \ inject_fault.o va_layout.o handle_exit.o \ guest.o debug.o reset.o sys_regs.o \ vgic-sys-reg-v3.o fpsimd.o pmu.o \ - arch_timer.o trng.o\ + arch_timer.o trng.o emulate-nested.o \ vgic/vgic.o vgic/vgic-init.o \ vgic/vgic-irqfd.o vgic/vgic-v2.o \ vgic/vgic-v3.o vgic/vgic-v4.o \ diff --git a/arch/arm64/kvm/emulate-nested.c b/arch/arm64/kvm/emulate-nested.c new file mode 100644 index 000000000000..ee91bcd925d8 --- /dev/null +++ b/arch/arm64/kvm/emulate-nested.c @@ -0,0 +1,176 @@ +/* + * Copyright (C) 2016 - Linaro and Columbia University + * Author: Jintack Lim + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +#include +#include + +#include +#include + +#include "hyp/include/hyp/adjust_pc.h" + +#include "trace.h" + +void kvm_emulate_nested_eret(struct kvm_vcpu *vcpu) +{ + u64 spsr, elr, mode; + bool direct_eret; + + /* + * Going through the whole put/load motions is a waste of time + * if this is a VHE guest hypervisor returning to its own + * userspace, or the hypervisor performing a local exception + * return. No need to save/restore registers, no need to + * switch S2 MMU. Just do the canonical ERET. + */ + spsr = vcpu_read_sys_reg(vcpu, SPSR_EL2); + mode = spsr & (PSR_MODE_MASK | PSR_MODE32_BIT); + + direct_eret = (mode == PSR_MODE_EL0t && + vcpu_el2_e2h_is_set(vcpu) && + vcpu_el2_tge_is_set(vcpu)); + direct_eret |= (mode == PSR_MODE_EL2h || mode == PSR_MODE_EL2t); + + if (direct_eret) { + *vcpu_pc(vcpu) = vcpu_read_sys_reg(vcpu, ELR_EL2); + *vcpu_cpsr(vcpu) = spsr; + trace_kvm_nested_eret(vcpu, *vcpu_pc(vcpu), spsr); + return; + } + + preempt_disable(); + kvm_arch_vcpu_put(vcpu); + + elr = __vcpu_sys_reg(vcpu, ELR_EL2); + + trace_kvm_nested_eret(vcpu, elr, spsr); + + /* + * Note that the current exception level is always the virtual EL2, + * since we set HCR_EL2.NV bit only when entering the virtual EL2. + */ + *vcpu_pc(vcpu) = elr; + *vcpu_cpsr(vcpu) = spsr; + + kvm_arch_vcpu_load(vcpu, smp_processor_id()); + preempt_enable(); +} + +static void kvm_inject_el2_exception(struct kvm_vcpu *vcpu, u64 esr_el2, + enum exception_type type) +{ + trace_kvm_inject_nested_exception(vcpu, esr_el2, type); + + switch (type) { + case except_type_sync: + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_ELx_SYNC; + break; + case except_type_irq: + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_ELx_IRQ; + break; + default: + WARN_ONCE(1, "Unsupported EL2 exception injection %d\n", type); + } + + vcpu->arch.flags |= (KVM_ARM64_EXCEPT_AA64_EL2 | + KVM_ARM64_PENDING_EXCEPTION); + + vcpu_write_sys_reg(vcpu, esr_el2, ESR_EL2); +} + +/* + * Emulate taking an exception to EL2. + * See ARM ARM J8.1.2 AArch64.TakeException() + */ +static int kvm_inject_nested(struct kvm_vcpu *vcpu, u64 esr_el2, + enum exception_type type) +{ + u64 pstate, mode; + bool direct_inject; + + if (!nested_virt_in_use(vcpu)) { + kvm_err("Unexpected call to %s for the non-nesting configuration\n", + __func__); + return -EINVAL; + } + + /* + * As for ERET, we can avoid doing too much on the injection path by + * checking that we either took the exception from a VHE host + * userspace or from vEL2. In these cases, there is no change in + * translation regime (or anything else), so let's do as little as + * possible. + */ + pstate = *vcpu_cpsr(vcpu); + mode = pstate & (PSR_MODE_MASK | PSR_MODE32_BIT); + + direct_inject = (mode == PSR_MODE_EL0t && + vcpu_el2_e2h_is_set(vcpu) && + vcpu_el2_tge_is_set(vcpu)); + direct_inject |= (mode == PSR_MODE_EL2h || mode == PSR_MODE_EL2t); + + if (direct_inject) { + kvm_inject_el2_exception(vcpu, esr_el2, type); + return 1; + } + + preempt_disable(); + kvm_arch_vcpu_put(vcpu); + + kvm_inject_el2_exception(vcpu, esr_el2, type); + + /* + * A hard requirement is that a switch between EL1 and EL2 + * contexts has to happen between a put/load, so that we can + * pick the correct timer and interrupt configuration, among + * other things. + * + * Make sure the exception actually took place before we load + * the new context. + */ + __adjust_pc(vcpu); + + kvm_arch_vcpu_load(vcpu, smp_processor_id()); + preempt_enable(); + + return 1; +} + +int kvm_inject_nested_sync(struct kvm_vcpu *vcpu, u64 esr_el2) +{ + return kvm_inject_nested(vcpu, esr_el2, except_type_sync); +} + +int kvm_inject_nested_irq(struct kvm_vcpu *vcpu) +{ + /* + * Do not inject an irq if the: + * - Current exception level is EL2, and + * - virtual HCR_EL2.TGE == 0 + * - virtual HCR_EL2.IMO == 0 + * + * See Table D1-17 "Physical interrupt target and masking when EL3 is + * not implemented and EL2 is implemented" in ARM DDI 0487C.a. + */ + + if (vcpu_mode_el2(vcpu) && !vcpu_el2_tge_is_set(vcpu) && + !(__vcpu_sys_reg(vcpu, HCR_EL2) & HCR_IMO)) + return 1; + + /* esr_el2 value doesn't matter for exits due to irqs. */ + return kvm_inject_nested(vcpu, 0, except_type_irq); +} diff --git a/arch/arm64/kvm/hyp/exception.c b/arch/arm64/kvm/hyp/exception.c index 73629094f903..b6424c01a85a 100644 --- a/arch/arm64/kvm/hyp/exception.c +++ b/arch/arm64/kvm/hyp/exception.c @@ -13,6 +13,7 @@ #include #include #include +#include #if !defined (__KVM_NVHE_HYPERVISOR__) && !defined (__KVM_VHE_HYPERVISOR__) #error Hypervisor code only! @@ -22,7 +23,9 @@ static inline u64 __vcpu_read_sys_reg(const struct kvm_vcpu *vcpu, int reg) { u64 val; - if (__vcpu_read_sys_reg_from_cpu(reg, &val)) + if (unlikely(nested_virt_in_use(vcpu))) + return vcpu_read_sys_reg(vcpu, reg); + else if (__vcpu_read_sys_reg_from_cpu(reg, &val)) return val; return __vcpu_sys_reg(vcpu, reg); @@ -30,14 +33,26 @@ static inline u64 __vcpu_read_sys_reg(const struct kvm_vcpu *vcpu, int reg) static inline void __vcpu_write_sys_reg(struct kvm_vcpu *vcpu, u64 val, int reg) { - if (__vcpu_write_sys_reg_to_cpu(val, reg)) + if (unlikely(nested_virt_in_use(vcpu))) + vcpu_write_sys_reg(vcpu, val, reg); + else if (__vcpu_write_sys_reg_to_cpu(val, reg)) return; __vcpu_sys_reg(vcpu, reg) = val; } -static void __vcpu_write_spsr(struct kvm_vcpu *vcpu, u64 val) +static void __vcpu_write_spsr(struct kvm_vcpu *vcpu, unsigned long target_mode, + u64 val) { + if (unlikely(nested_virt_in_use(vcpu))) { + if (target_mode == PSR_MODE_EL1h) + vcpu_write_sys_reg(vcpu, val, SPSR_EL1); + else + vcpu_write_sys_reg(vcpu, val, SPSR_EL2); + + return; + } + write_sysreg_el1(val, SYS_SPSR); } @@ -97,6 +112,11 @@ static void enter_exception64(struct kvm_vcpu *vcpu, unsigned long target_mode, sctlr = __vcpu_read_sys_reg(vcpu, SCTLR_EL1); __vcpu_write_sys_reg(vcpu, *vcpu_pc(vcpu), ELR_EL1); break; + case PSR_MODE_EL2h: + vbar = __vcpu_read_sys_reg(vcpu, VBAR_EL2); + sctlr = __vcpu_read_sys_reg(vcpu, SCTLR_EL2); + __vcpu_write_sys_reg(vcpu, *vcpu_pc(vcpu), ELR_EL2); + break; default: /* Don't do that */ BUG(); @@ -148,7 +168,7 @@ static void enter_exception64(struct kvm_vcpu *vcpu, unsigned long target_mode, new |= target_mode; *vcpu_cpsr(vcpu) = new; - __vcpu_write_spsr(vcpu, old); + __vcpu_write_spsr(vcpu, target_mode, old); } /* @@ -319,11 +339,22 @@ void kvm_inject_exception(struct kvm_vcpu *vcpu) KVM_ARM64_EXCEPT_AA64_EL1): enter_exception64(vcpu, PSR_MODE_EL1h, except_type_sync); break; + + case (KVM_ARM64_EXCEPT_AA64_ELx_SYNC | + KVM_ARM64_EXCEPT_AA64_EL2): + enter_exception64(vcpu, PSR_MODE_EL2h, except_type_sync); + break; + + case (KVM_ARM64_EXCEPT_AA64_ELx_IRQ | + KVM_ARM64_EXCEPT_AA64_EL2): + enter_exception64(vcpu, PSR_MODE_EL2h, except_type_irq); + break; + default: /* - * Only EL1_SYNC makes sense so far, EL2_{SYNC,IRQ} - * will be implemented at some point. Everything - * else gets silently ignored. + * Only EL1_SYNC and EL2_{SYNC,IRQ} makes + * sense so far. Everything else gets silently + * ignored. */ break; } diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c index b47df73e98d7..06df0bb848ca 100644 --- a/arch/arm64/kvm/inject_fault.c +++ b/arch/arm64/kvm/inject_fault.c @@ -12,19 +12,53 @@ #include #include +#include #include +static void pend_sync_exception(struct kvm_vcpu *vcpu) +{ + vcpu->arch.flags |= (KVM_ARM64_EXCEPT_AA64_ELx_SYNC | + KVM_ARM64_PENDING_EXCEPTION); + + /* If not nesting, EL1 is the only possible exception target */ + if (likely(!nested_virt_in_use(vcpu))) { + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_EL1; + return; + } + + /* + * With NV, we need to pick between EL1 and EL2. Note that we + * never deal with a nesting exception here, hence never + * changing context, and the exception itself can be delayed + * until the next entry. + */ + switch(*vcpu_cpsr(vcpu) & PSR_MODE_MASK) { + case PSR_MODE_EL2h: + case PSR_MODE_EL2t: + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_EL2; + break; + case PSR_MODE_EL1h: + case PSR_MODE_EL1t: + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_EL1; + break; + case PSR_MODE_EL0t: + if (vcpu_el2_tge_is_set(vcpu) & HCR_TGE) + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_EL2; + else + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_EL1; + break; + default: + BUG(); + } +} + static void inject_abt64(struct kvm_vcpu *vcpu, bool is_iabt, unsigned long addr) { unsigned long cpsr = *vcpu_cpsr(vcpu); bool is_aarch32 = vcpu_mode_is_32bit(vcpu); u32 esr = 0; - vcpu->arch.flags |= (KVM_ARM64_EXCEPT_AA64_EL1 | - KVM_ARM64_EXCEPT_AA64_ELx_SYNC | - KVM_ARM64_PENDING_EXCEPTION); - - vcpu_write_sys_reg(vcpu, addr, FAR_EL1); + pend_sync_exception(vcpu); /* * Build an {i,d}abort, depending on the level and the @@ -45,16 +79,22 @@ static void inject_abt64(struct kvm_vcpu *vcpu, bool is_iabt, unsigned long addr if (!is_iabt) esr |= ESR_ELx_EC_DABT_LOW << ESR_ELx_EC_SHIFT; - vcpu_write_sys_reg(vcpu, esr | ESR_ELx_FSC_EXTABT, ESR_EL1); + esr |= ESR_ELx_FSC_EXTABT; + + if (vcpu->arch.flags & KVM_ARM64_EXCEPT_AA64_EL1) { + vcpu_write_sys_reg(vcpu, addr, FAR_EL1); + vcpu_write_sys_reg(vcpu, esr, ESR_EL1); + } else { + vcpu_write_sys_reg(vcpu, addr, FAR_EL2); + vcpu_write_sys_reg(vcpu, esr, ESR_EL2); + } } static void inject_undef64(struct kvm_vcpu *vcpu) { u32 esr = (ESR_ELx_EC_UNKNOWN << ESR_ELx_EC_SHIFT); - vcpu->arch.flags |= (KVM_ARM64_EXCEPT_AA64_EL1 | - KVM_ARM64_EXCEPT_AA64_ELx_SYNC | - KVM_ARM64_PENDING_EXCEPTION); + pend_sync_exception(vcpu); /* * Build an unknown exception, depending on the instruction @@ -63,7 +103,10 @@ static void inject_undef64(struct kvm_vcpu *vcpu) if (kvm_vcpu_trap_il_is32bit(vcpu)) esr |= ESR_ELx_IL; - vcpu_write_sys_reg(vcpu, esr, ESR_EL1); + if (vcpu->arch.flags & KVM_ARM64_EXCEPT_AA64_EL1) + vcpu_write_sys_reg(vcpu, esr, ESR_EL1); + else + vcpu_write_sys_reg(vcpu, esr, ESR_EL2); } #define DFSR_FSC_EXTABT_LPAE 0x10 diff --git a/arch/arm64/kvm/trace_arm.h b/arch/arm64/kvm/trace_arm.h index 33e4e7dd2719..f3e46a976125 100644 --- a/arch/arm64/kvm/trace_arm.h +++ b/arch/arm64/kvm/trace_arm.h @@ -2,6 +2,7 @@ #if !defined(_TRACE_ARM_ARM64_KVM_H) || defined(TRACE_HEADER_MULTI_READ) #define _TRACE_ARM_ARM64_KVM_H +#include #include #include @@ -301,6 +302,64 @@ TRACE_EVENT(kvm_timer_emulate, __entry->timer_idx, __entry->should_fire) ); +TRACE_EVENT(kvm_nested_eret, + TP_PROTO(struct kvm_vcpu *vcpu, unsigned long elr_el2, + unsigned long spsr_el2), + TP_ARGS(vcpu, elr_el2, spsr_el2), + + TP_STRUCT__entry( + __field(struct kvm_vcpu *, vcpu) + __field(unsigned long, elr_el2) + __field(unsigned long, spsr_el2) + __field(unsigned long, target_mode) + __field(unsigned long, hcr_el2) + ), + + TP_fast_assign( + __entry->vcpu = vcpu; + __entry->elr_el2 = elr_el2; + __entry->spsr_el2 = spsr_el2; + __entry->target_mode = spsr_el2 & (PSR_MODE_MASK | PSR_MODE32_BIT); + __entry->hcr_el2 = __vcpu_sys_reg(vcpu, HCR_EL2); + ), + + TP_printk("elr_el2: 0x%lx spsr_el2: 0x%08lx (M: %s) hcr_el2: %lx", + __entry->elr_el2, __entry->spsr_el2, + __print_symbolic(__entry->target_mode, kvm_mode_names), + __entry->hcr_el2) +); + +TRACE_EVENT(kvm_inject_nested_exception, + TP_PROTO(struct kvm_vcpu *vcpu, u64 esr_el2, int type), + TP_ARGS(vcpu, esr_el2, type), + + TP_STRUCT__entry( + __field(struct kvm_vcpu *, vcpu) + __field(unsigned long, esr_el2) + __field(int, type) + __field(unsigned long, spsr_el2) + __field(unsigned long, pc) + __field(unsigned long, source_mode) + __field(unsigned long, hcr_el2) + ), + + TP_fast_assign( + __entry->vcpu = vcpu; + __entry->esr_el2 = esr_el2; + __entry->type = type; + __entry->spsr_el2 = *vcpu_cpsr(vcpu); + __entry->pc = *vcpu_pc(vcpu); + __entry->source_mode = *vcpu_cpsr(vcpu) & (PSR_MODE_MASK | PSR_MODE32_BIT); + __entry->hcr_el2 = __vcpu_sys_reg(vcpu, HCR_EL2); + ), + + TP_printk("%s: esr_el2 0x%lx elr_el2: 0x%lx spsr_el2: 0x%08lx (M: %s) hcr_el2: %lx", + __print_symbolic(__entry->type, kvm_exception_type_names), + __entry->esr_el2, __entry->pc, __entry->spsr_el2, + __print_symbolic(__entry->source_mode, kvm_mode_names), + __entry->hcr_el2) +); + #endif /* _TRACE_ARM_ARM64_KVM_H */ #undef TRACE_INCLUDE_PATH -- 2.29.2 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,USER_AGENT_GIT autolearn=ham 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 99BEEC43460 for ; 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Mon, 10 May 2021 12:59:51 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id wv4n8zAL4FT4 for ; Mon, 10 May 2021 12:59:49 -0400 (EDT) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 1CB054B273 for ; Mon, 10 May 2021 12:59:46 -0400 (EDT) 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 A225B6157E; Mon, 10 May 2021 16:59:45 +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 4.94.2) (envelope-from ) id 1lg9Fv-000Uqg-Sy; Mon, 10 May 2021 17:59:44 +0100 From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org Subject: [PATCH v4 09/66] KVM: arm64: nv: Support virtual EL2 exceptions Date: Mon, 10 May 2021 17:58:23 +0100 Message-Id: <20210510165920.1913477-10-maz@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210510165920.1913477-1-maz@kernel.org> References: <20210510165920.1913477-1-maz@kernel.org> MIME-Version: 1.0 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, haibo.xu@linaro.org, james.morse@arm.com, suzuki.poulose@arm.com, alexandru.elisei@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 Cc: kernel-team@android.com, Andre Przywara , Jintack Lim X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu From: Jintack Lim Support injecting exceptions and performing exception returns to and from virtual EL2. This must be done entirely in software except when taking an exception from vEL0 to vEL2 when the virtual HCR_EL2.{E2H,TGE} == {1,1} (a VHE guest hypervisor). Signed-off-by: Jintack Lim Signed-off-by: Christoffer Dall [maz: switch to common exception injection framework] Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_arm.h | 17 +++ arch/arm64/include/asm/kvm_emulate.h | 10 ++ arch/arm64/kvm/Makefile | 2 +- arch/arm64/kvm/emulate-nested.c | 176 +++++++++++++++++++++++++++ arch/arm64/kvm/hyp/exception.c | 45 +++++-- arch/arm64/kvm/inject_fault.c | 63 ++++++++-- arch/arm64/kvm/trace_arm.h | 59 +++++++++ 7 files changed, 354 insertions(+), 18 deletions(-) create mode 100644 arch/arm64/kvm/emulate-nested.c diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h index 692c9049befa..e27da4165d43 100644 --- a/arch/arm64/include/asm/kvm_arm.h +++ b/arch/arm64/include/asm/kvm_arm.h @@ -335,4 +335,21 @@ #define CPACR_EL1_TTA (1 << 28) #define CPACR_EL1_DEFAULT (CPACR_EL1_FPEN | CPACR_EL1_ZEN_EL1EN) +#define kvm_mode_names \ + { PSR_MODE_EL0t, "EL0t" }, \ + { PSR_MODE_EL1t, "EL1t" }, \ + { PSR_MODE_EL1h, "EL1h" }, \ + { PSR_MODE_EL2t, "EL2t" }, \ + { PSR_MODE_EL2h, "EL2h" }, \ + { PSR_MODE_EL3t, "EL3t" }, \ + { PSR_MODE_EL3h, "EL3h" }, \ + { PSR_AA32_MODE_USR, "32-bit USR" }, \ + { PSR_AA32_MODE_FIQ, "32-bit FIQ" }, \ + { PSR_AA32_MODE_IRQ, "32-bit IRQ" }, \ + { PSR_AA32_MODE_SVC, "32-bit SVC" }, \ + { PSR_AA32_MODE_ABT, "32-bit ABT" }, \ + { PSR_AA32_MODE_HYP, "32-bit HYP" }, \ + { PSR_AA32_MODE_UND, "32-bit UND" }, \ + { PSR_AA32_MODE_SYS, "32-bit SYS" } + #endif /* __ARM64_KVM_ARM_H__ */ diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h index 706ef06c5f2b..1c10fbe7d1c3 100644 --- a/arch/arm64/include/asm/kvm_emulate.h +++ b/arch/arm64/include/asm/kvm_emulate.h @@ -33,6 +33,12 @@ enum exception_type { except_type_serror = 0x180, }; +#define kvm_exception_type_names \ + { except_type_sync, "SYNC" }, \ + { except_type_irq, "IRQ" }, \ + { except_type_fiq, "FIQ" }, \ + { except_type_serror, "SERROR" } + bool kvm_condition_valid32(const struct kvm_vcpu *vcpu); void kvm_skip_instr32(struct kvm_vcpu *vcpu); @@ -41,6 +47,10 @@ void kvm_inject_vabt(struct kvm_vcpu *vcpu); void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr); void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr); +void kvm_emulate_nested_eret(struct kvm_vcpu *vcpu); +int kvm_inject_nested_sync(struct kvm_vcpu *vcpu, u64 esr_el2); +int kvm_inject_nested_irq(struct kvm_vcpu *vcpu); + static __always_inline bool vcpu_el1_is_32bit(struct kvm_vcpu *vcpu) { return !(vcpu->arch.hcr_el2 & HCR_RW); diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index 589921392cb1..ebf6ddb3cd77 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -16,7 +16,7 @@ kvm-y := $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o \ inject_fault.o va_layout.o handle_exit.o \ guest.o debug.o reset.o sys_regs.o \ vgic-sys-reg-v3.o fpsimd.o pmu.o \ - arch_timer.o trng.o\ + arch_timer.o trng.o emulate-nested.o \ vgic/vgic.o vgic/vgic-init.o \ vgic/vgic-irqfd.o vgic/vgic-v2.o \ vgic/vgic-v3.o vgic/vgic-v4.o \ diff --git a/arch/arm64/kvm/emulate-nested.c b/arch/arm64/kvm/emulate-nested.c new file mode 100644 index 000000000000..ee91bcd925d8 --- /dev/null +++ b/arch/arm64/kvm/emulate-nested.c @@ -0,0 +1,176 @@ +/* + * Copyright (C) 2016 - Linaro and Columbia University + * Author: Jintack Lim + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +#include +#include + +#include +#include + +#include "hyp/include/hyp/adjust_pc.h" + +#include "trace.h" + +void kvm_emulate_nested_eret(struct kvm_vcpu *vcpu) +{ + u64 spsr, elr, mode; + bool direct_eret; + + /* + * Going through the whole put/load motions is a waste of time + * if this is a VHE guest hypervisor returning to its own + * userspace, or the hypervisor performing a local exception + * return. No need to save/restore registers, no need to + * switch S2 MMU. Just do the canonical ERET. + */ + spsr = vcpu_read_sys_reg(vcpu, SPSR_EL2); + mode = spsr & (PSR_MODE_MASK | PSR_MODE32_BIT); + + direct_eret = (mode == PSR_MODE_EL0t && + vcpu_el2_e2h_is_set(vcpu) && + vcpu_el2_tge_is_set(vcpu)); + direct_eret |= (mode == PSR_MODE_EL2h || mode == PSR_MODE_EL2t); + + if (direct_eret) { + *vcpu_pc(vcpu) = vcpu_read_sys_reg(vcpu, ELR_EL2); + *vcpu_cpsr(vcpu) = spsr; + trace_kvm_nested_eret(vcpu, *vcpu_pc(vcpu), spsr); + return; + } + + preempt_disable(); + kvm_arch_vcpu_put(vcpu); + + elr = __vcpu_sys_reg(vcpu, ELR_EL2); + + trace_kvm_nested_eret(vcpu, elr, spsr); + + /* + * Note that the current exception level is always the virtual EL2, + * since we set HCR_EL2.NV bit only when entering the virtual EL2. + */ + *vcpu_pc(vcpu) = elr; + *vcpu_cpsr(vcpu) = spsr; + + kvm_arch_vcpu_load(vcpu, smp_processor_id()); + preempt_enable(); +} + +static void kvm_inject_el2_exception(struct kvm_vcpu *vcpu, u64 esr_el2, + enum exception_type type) +{ + trace_kvm_inject_nested_exception(vcpu, esr_el2, type); + + switch (type) { + case except_type_sync: + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_ELx_SYNC; + break; + case except_type_irq: + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_ELx_IRQ; + break; + default: + WARN_ONCE(1, "Unsupported EL2 exception injection %d\n", type); + } + + vcpu->arch.flags |= (KVM_ARM64_EXCEPT_AA64_EL2 | + KVM_ARM64_PENDING_EXCEPTION); + + vcpu_write_sys_reg(vcpu, esr_el2, ESR_EL2); +} + +/* + * Emulate taking an exception to EL2. + * See ARM ARM J8.1.2 AArch64.TakeException() + */ +static int kvm_inject_nested(struct kvm_vcpu *vcpu, u64 esr_el2, + enum exception_type type) +{ + u64 pstate, mode; + bool direct_inject; + + if (!nested_virt_in_use(vcpu)) { + kvm_err("Unexpected call to %s for the non-nesting configuration\n", + __func__); + return -EINVAL; + } + + /* + * As for ERET, we can avoid doing too much on the injection path by + * checking that we either took the exception from a VHE host + * userspace or from vEL2. In these cases, there is no change in + * translation regime (or anything else), so let's do as little as + * possible. + */ + pstate = *vcpu_cpsr(vcpu); + mode = pstate & (PSR_MODE_MASK | PSR_MODE32_BIT); + + direct_inject = (mode == PSR_MODE_EL0t && + vcpu_el2_e2h_is_set(vcpu) && + vcpu_el2_tge_is_set(vcpu)); + direct_inject |= (mode == PSR_MODE_EL2h || mode == PSR_MODE_EL2t); + + if (direct_inject) { + kvm_inject_el2_exception(vcpu, esr_el2, type); + return 1; + } + + preempt_disable(); + kvm_arch_vcpu_put(vcpu); + + kvm_inject_el2_exception(vcpu, esr_el2, type); + + /* + * A hard requirement is that a switch between EL1 and EL2 + * contexts has to happen between a put/load, so that we can + * pick the correct timer and interrupt configuration, among + * other things. + * + * Make sure the exception actually took place before we load + * the new context. + */ + __adjust_pc(vcpu); + + kvm_arch_vcpu_load(vcpu, smp_processor_id()); + preempt_enable(); + + return 1; +} + +int kvm_inject_nested_sync(struct kvm_vcpu *vcpu, u64 esr_el2) +{ + return kvm_inject_nested(vcpu, esr_el2, except_type_sync); +} + +int kvm_inject_nested_irq(struct kvm_vcpu *vcpu) +{ + /* + * Do not inject an irq if the: + * - Current exception level is EL2, and + * - virtual HCR_EL2.TGE == 0 + * - virtual HCR_EL2.IMO == 0 + * + * See Table D1-17 "Physical interrupt target and masking when EL3 is + * not implemented and EL2 is implemented" in ARM DDI 0487C.a. + */ + + if (vcpu_mode_el2(vcpu) && !vcpu_el2_tge_is_set(vcpu) && + !(__vcpu_sys_reg(vcpu, HCR_EL2) & HCR_IMO)) + return 1; + + /* esr_el2 value doesn't matter for exits due to irqs. */ + return kvm_inject_nested(vcpu, 0, except_type_irq); +} diff --git a/arch/arm64/kvm/hyp/exception.c b/arch/arm64/kvm/hyp/exception.c index 73629094f903..b6424c01a85a 100644 --- a/arch/arm64/kvm/hyp/exception.c +++ b/arch/arm64/kvm/hyp/exception.c @@ -13,6 +13,7 @@ #include #include #include +#include #if !defined (__KVM_NVHE_HYPERVISOR__) && !defined (__KVM_VHE_HYPERVISOR__) #error Hypervisor code only! @@ -22,7 +23,9 @@ static inline u64 __vcpu_read_sys_reg(const struct kvm_vcpu *vcpu, int reg) { u64 val; - if (__vcpu_read_sys_reg_from_cpu(reg, &val)) + if (unlikely(nested_virt_in_use(vcpu))) + return vcpu_read_sys_reg(vcpu, reg); + else if (__vcpu_read_sys_reg_from_cpu(reg, &val)) return val; return __vcpu_sys_reg(vcpu, reg); @@ -30,14 +33,26 @@ static inline u64 __vcpu_read_sys_reg(const struct kvm_vcpu *vcpu, int reg) static inline void __vcpu_write_sys_reg(struct kvm_vcpu *vcpu, u64 val, int reg) { - if (__vcpu_write_sys_reg_to_cpu(val, reg)) + if (unlikely(nested_virt_in_use(vcpu))) + vcpu_write_sys_reg(vcpu, val, reg); + else if (__vcpu_write_sys_reg_to_cpu(val, reg)) return; __vcpu_sys_reg(vcpu, reg) = val; } -static void __vcpu_write_spsr(struct kvm_vcpu *vcpu, u64 val) +static void __vcpu_write_spsr(struct kvm_vcpu *vcpu, unsigned long target_mode, + u64 val) { + if (unlikely(nested_virt_in_use(vcpu))) { + if (target_mode == PSR_MODE_EL1h) + vcpu_write_sys_reg(vcpu, val, SPSR_EL1); + else + vcpu_write_sys_reg(vcpu, val, SPSR_EL2); + + return; + } + write_sysreg_el1(val, SYS_SPSR); } @@ -97,6 +112,11 @@ static void enter_exception64(struct kvm_vcpu *vcpu, unsigned long target_mode, sctlr = __vcpu_read_sys_reg(vcpu, SCTLR_EL1); __vcpu_write_sys_reg(vcpu, *vcpu_pc(vcpu), ELR_EL1); break; + case PSR_MODE_EL2h: + vbar = __vcpu_read_sys_reg(vcpu, VBAR_EL2); + sctlr = __vcpu_read_sys_reg(vcpu, SCTLR_EL2); + __vcpu_write_sys_reg(vcpu, *vcpu_pc(vcpu), ELR_EL2); + break; default: /* Don't do that */ BUG(); @@ -148,7 +168,7 @@ static void enter_exception64(struct kvm_vcpu *vcpu, unsigned long target_mode, new |= target_mode; *vcpu_cpsr(vcpu) = new; - __vcpu_write_spsr(vcpu, old); + __vcpu_write_spsr(vcpu, target_mode, old); } /* @@ -319,11 +339,22 @@ void kvm_inject_exception(struct kvm_vcpu *vcpu) KVM_ARM64_EXCEPT_AA64_EL1): enter_exception64(vcpu, PSR_MODE_EL1h, except_type_sync); break; + + case (KVM_ARM64_EXCEPT_AA64_ELx_SYNC | + KVM_ARM64_EXCEPT_AA64_EL2): + enter_exception64(vcpu, PSR_MODE_EL2h, except_type_sync); + break; + + case (KVM_ARM64_EXCEPT_AA64_ELx_IRQ | + KVM_ARM64_EXCEPT_AA64_EL2): + enter_exception64(vcpu, PSR_MODE_EL2h, except_type_irq); + break; + default: /* - * Only EL1_SYNC makes sense so far, EL2_{SYNC,IRQ} - * will be implemented at some point. Everything - * else gets silently ignored. + * Only EL1_SYNC and EL2_{SYNC,IRQ} makes + * sense so far. Everything else gets silently + * ignored. */ break; } diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c index b47df73e98d7..06df0bb848ca 100644 --- a/arch/arm64/kvm/inject_fault.c +++ b/arch/arm64/kvm/inject_fault.c @@ -12,19 +12,53 @@ #include #include +#include #include +static void pend_sync_exception(struct kvm_vcpu *vcpu) +{ + vcpu->arch.flags |= (KVM_ARM64_EXCEPT_AA64_ELx_SYNC | + KVM_ARM64_PENDING_EXCEPTION); + + /* If not nesting, EL1 is the only possible exception target */ + if (likely(!nested_virt_in_use(vcpu))) { + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_EL1; + return; + } + + /* + * With NV, we need to pick between EL1 and EL2. Note that we + * never deal with a nesting exception here, hence never + * changing context, and the exception itself can be delayed + * until the next entry. + */ + switch(*vcpu_cpsr(vcpu) & PSR_MODE_MASK) { + case PSR_MODE_EL2h: + case PSR_MODE_EL2t: + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_EL2; + break; + case PSR_MODE_EL1h: + case PSR_MODE_EL1t: + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_EL1; + break; + case PSR_MODE_EL0t: + if (vcpu_el2_tge_is_set(vcpu) & HCR_TGE) + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_EL2; + else + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_EL1; + break; + default: + BUG(); + } +} + static void inject_abt64(struct kvm_vcpu *vcpu, bool is_iabt, unsigned long addr) { unsigned long cpsr = *vcpu_cpsr(vcpu); bool is_aarch32 = vcpu_mode_is_32bit(vcpu); u32 esr = 0; - vcpu->arch.flags |= (KVM_ARM64_EXCEPT_AA64_EL1 | - KVM_ARM64_EXCEPT_AA64_ELx_SYNC | - KVM_ARM64_PENDING_EXCEPTION); - - vcpu_write_sys_reg(vcpu, addr, FAR_EL1); + pend_sync_exception(vcpu); /* * Build an {i,d}abort, depending on the level and the @@ -45,16 +79,22 @@ static void inject_abt64(struct kvm_vcpu *vcpu, bool is_iabt, unsigned long addr if (!is_iabt) esr |= ESR_ELx_EC_DABT_LOW << ESR_ELx_EC_SHIFT; - vcpu_write_sys_reg(vcpu, esr | ESR_ELx_FSC_EXTABT, ESR_EL1); + esr |= ESR_ELx_FSC_EXTABT; + + if (vcpu->arch.flags & KVM_ARM64_EXCEPT_AA64_EL1) { + vcpu_write_sys_reg(vcpu, addr, FAR_EL1); + vcpu_write_sys_reg(vcpu, esr, ESR_EL1); + } else { + vcpu_write_sys_reg(vcpu, addr, FAR_EL2); + vcpu_write_sys_reg(vcpu, esr, ESR_EL2); + } } static void inject_undef64(struct kvm_vcpu *vcpu) { u32 esr = (ESR_ELx_EC_UNKNOWN << ESR_ELx_EC_SHIFT); - vcpu->arch.flags |= (KVM_ARM64_EXCEPT_AA64_EL1 | - KVM_ARM64_EXCEPT_AA64_ELx_SYNC | - KVM_ARM64_PENDING_EXCEPTION); + pend_sync_exception(vcpu); /* * Build an unknown exception, depending on the instruction @@ -63,7 +103,10 @@ static void inject_undef64(struct kvm_vcpu *vcpu) if (kvm_vcpu_trap_il_is32bit(vcpu)) esr |= ESR_ELx_IL; - vcpu_write_sys_reg(vcpu, esr, ESR_EL1); + if (vcpu->arch.flags & KVM_ARM64_EXCEPT_AA64_EL1) + vcpu_write_sys_reg(vcpu, esr, ESR_EL1); + else + vcpu_write_sys_reg(vcpu, esr, ESR_EL2); } #define DFSR_FSC_EXTABT_LPAE 0x10 diff --git a/arch/arm64/kvm/trace_arm.h b/arch/arm64/kvm/trace_arm.h index 33e4e7dd2719..f3e46a976125 100644 --- a/arch/arm64/kvm/trace_arm.h +++ b/arch/arm64/kvm/trace_arm.h @@ -2,6 +2,7 @@ #if !defined(_TRACE_ARM_ARM64_KVM_H) || defined(TRACE_HEADER_MULTI_READ) #define _TRACE_ARM_ARM64_KVM_H +#include #include #include @@ -301,6 +302,64 @@ TRACE_EVENT(kvm_timer_emulate, __entry->timer_idx, __entry->should_fire) ); +TRACE_EVENT(kvm_nested_eret, + TP_PROTO(struct kvm_vcpu *vcpu, unsigned long elr_el2, + unsigned long spsr_el2), + TP_ARGS(vcpu, elr_el2, spsr_el2), + + TP_STRUCT__entry( + __field(struct kvm_vcpu *, vcpu) + __field(unsigned long, elr_el2) + __field(unsigned long, spsr_el2) + __field(unsigned long, target_mode) + __field(unsigned long, hcr_el2) + ), + + TP_fast_assign( + __entry->vcpu = vcpu; + __entry->elr_el2 = elr_el2; + __entry->spsr_el2 = spsr_el2; + __entry->target_mode = spsr_el2 & (PSR_MODE_MASK | PSR_MODE32_BIT); + __entry->hcr_el2 = __vcpu_sys_reg(vcpu, HCR_EL2); + ), + + TP_printk("elr_el2: 0x%lx spsr_el2: 0x%08lx (M: %s) hcr_el2: %lx", + __entry->elr_el2, __entry->spsr_el2, + __print_symbolic(__entry->target_mode, kvm_mode_names), + __entry->hcr_el2) +); + +TRACE_EVENT(kvm_inject_nested_exception, + TP_PROTO(struct kvm_vcpu *vcpu, u64 esr_el2, int type), + TP_ARGS(vcpu, esr_el2, type), + + TP_STRUCT__entry( + __field(struct kvm_vcpu *, vcpu) + __field(unsigned long, esr_el2) + __field(int, type) + __field(unsigned long, spsr_el2) + __field(unsigned long, pc) + __field(unsigned long, source_mode) + __field(unsigned long, hcr_el2) + ), + + TP_fast_assign( + __entry->vcpu = vcpu; + __entry->esr_el2 = esr_el2; + __entry->type = type; + __entry->spsr_el2 = *vcpu_cpsr(vcpu); + __entry->pc = *vcpu_pc(vcpu); + __entry->source_mode = *vcpu_cpsr(vcpu) & (PSR_MODE_MASK | PSR_MODE32_BIT); + __entry->hcr_el2 = __vcpu_sys_reg(vcpu, HCR_EL2); + ), + + TP_printk("%s: esr_el2 0x%lx elr_el2: 0x%lx spsr_el2: 0x%08lx (M: %s) hcr_el2: %lx", + __print_symbolic(__entry->type, kvm_exception_type_names), + __entry->esr_el2, __entry->pc, __entry->spsr_el2, + __print_symbolic(__entry->source_mode, kvm_mode_names), + __entry->hcr_el2) +); + #endif /* _TRACE_ARM_ARM64_KVM_H */ #undef TRACE_INCLUDE_PATH -- 2.29.2 _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm 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=-17.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,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 22056C433B4 for ; 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Mon, 10 May 2021 17:59:44 +0100 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 , Haibo Xu , James Morse , Suzuki K Poulose , Alexandru Elisei , kernel-team@android.com, Jintack Lim Subject: [PATCH v4 09/66] KVM: arm64: nv: Support virtual EL2 exceptions Date: Mon, 10 May 2021 17:58:23 +0100 Message-Id: <20210510165920.1913477-10-maz@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210510165920.1913477-1-maz@kernel.org> References: <20210510165920.1913477-1-maz@kernel.org> MIME-Version: 1.0 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, haibo.xu@linaro.org, james.morse@arm.com, suzuki.poulose@arm.com, alexandru.elisei@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 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210510_095946_145148_0AAB4F18 X-CRM114-Status: GOOD ( 35.14 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Jintack Lim Support injecting exceptions and performing exception returns to and from virtual EL2. This must be done entirely in software except when taking an exception from vEL0 to vEL2 when the virtual HCR_EL2.{E2H,TGE} == {1,1} (a VHE guest hypervisor). Signed-off-by: Jintack Lim Signed-off-by: Christoffer Dall [maz: switch to common exception injection framework] Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_arm.h | 17 +++ arch/arm64/include/asm/kvm_emulate.h | 10 ++ arch/arm64/kvm/Makefile | 2 +- arch/arm64/kvm/emulate-nested.c | 176 +++++++++++++++++++++++++++ arch/arm64/kvm/hyp/exception.c | 45 +++++-- arch/arm64/kvm/inject_fault.c | 63 ++++++++-- arch/arm64/kvm/trace_arm.h | 59 +++++++++ 7 files changed, 354 insertions(+), 18 deletions(-) create mode 100644 arch/arm64/kvm/emulate-nested.c diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h index 692c9049befa..e27da4165d43 100644 --- a/arch/arm64/include/asm/kvm_arm.h +++ b/arch/arm64/include/asm/kvm_arm.h @@ -335,4 +335,21 @@ #define CPACR_EL1_TTA (1 << 28) #define CPACR_EL1_DEFAULT (CPACR_EL1_FPEN | CPACR_EL1_ZEN_EL1EN) +#define kvm_mode_names \ + { PSR_MODE_EL0t, "EL0t" }, \ + { PSR_MODE_EL1t, "EL1t" }, \ + { PSR_MODE_EL1h, "EL1h" }, \ + { PSR_MODE_EL2t, "EL2t" }, \ + { PSR_MODE_EL2h, "EL2h" }, \ + { PSR_MODE_EL3t, "EL3t" }, \ + { PSR_MODE_EL3h, "EL3h" }, \ + { PSR_AA32_MODE_USR, "32-bit USR" }, \ + { PSR_AA32_MODE_FIQ, "32-bit FIQ" }, \ + { PSR_AA32_MODE_IRQ, "32-bit IRQ" }, \ + { PSR_AA32_MODE_SVC, "32-bit SVC" }, \ + { PSR_AA32_MODE_ABT, "32-bit ABT" }, \ + { PSR_AA32_MODE_HYP, "32-bit HYP" }, \ + { PSR_AA32_MODE_UND, "32-bit UND" }, \ + { PSR_AA32_MODE_SYS, "32-bit SYS" } + #endif /* __ARM64_KVM_ARM_H__ */ diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h index 706ef06c5f2b..1c10fbe7d1c3 100644 --- a/arch/arm64/include/asm/kvm_emulate.h +++ b/arch/arm64/include/asm/kvm_emulate.h @@ -33,6 +33,12 @@ enum exception_type { except_type_serror = 0x180, }; +#define kvm_exception_type_names \ + { except_type_sync, "SYNC" }, \ + { except_type_irq, "IRQ" }, \ + { except_type_fiq, "FIQ" }, \ + { except_type_serror, "SERROR" } + bool kvm_condition_valid32(const struct kvm_vcpu *vcpu); void kvm_skip_instr32(struct kvm_vcpu *vcpu); @@ -41,6 +47,10 @@ void kvm_inject_vabt(struct kvm_vcpu *vcpu); void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr); void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr); +void kvm_emulate_nested_eret(struct kvm_vcpu *vcpu); +int kvm_inject_nested_sync(struct kvm_vcpu *vcpu, u64 esr_el2); +int kvm_inject_nested_irq(struct kvm_vcpu *vcpu); + static __always_inline bool vcpu_el1_is_32bit(struct kvm_vcpu *vcpu) { return !(vcpu->arch.hcr_el2 & HCR_RW); diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index 589921392cb1..ebf6ddb3cd77 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -16,7 +16,7 @@ kvm-y := $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o \ inject_fault.o va_layout.o handle_exit.o \ guest.o debug.o reset.o sys_regs.o \ vgic-sys-reg-v3.o fpsimd.o pmu.o \ - arch_timer.o trng.o\ + arch_timer.o trng.o emulate-nested.o \ vgic/vgic.o vgic/vgic-init.o \ vgic/vgic-irqfd.o vgic/vgic-v2.o \ vgic/vgic-v3.o vgic/vgic-v4.o \ diff --git a/arch/arm64/kvm/emulate-nested.c b/arch/arm64/kvm/emulate-nested.c new file mode 100644 index 000000000000..ee91bcd925d8 --- /dev/null +++ b/arch/arm64/kvm/emulate-nested.c @@ -0,0 +1,176 @@ +/* + * Copyright (C) 2016 - Linaro and Columbia University + * Author: Jintack Lim + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +#include +#include + +#include +#include + +#include "hyp/include/hyp/adjust_pc.h" + +#include "trace.h" + +void kvm_emulate_nested_eret(struct kvm_vcpu *vcpu) +{ + u64 spsr, elr, mode; + bool direct_eret; + + /* + * Going through the whole put/load motions is a waste of time + * if this is a VHE guest hypervisor returning to its own + * userspace, or the hypervisor performing a local exception + * return. No need to save/restore registers, no need to + * switch S2 MMU. Just do the canonical ERET. + */ + spsr = vcpu_read_sys_reg(vcpu, SPSR_EL2); + mode = spsr & (PSR_MODE_MASK | PSR_MODE32_BIT); + + direct_eret = (mode == PSR_MODE_EL0t && + vcpu_el2_e2h_is_set(vcpu) && + vcpu_el2_tge_is_set(vcpu)); + direct_eret |= (mode == PSR_MODE_EL2h || mode == PSR_MODE_EL2t); + + if (direct_eret) { + *vcpu_pc(vcpu) = vcpu_read_sys_reg(vcpu, ELR_EL2); + *vcpu_cpsr(vcpu) = spsr; + trace_kvm_nested_eret(vcpu, *vcpu_pc(vcpu), spsr); + return; + } + + preempt_disable(); + kvm_arch_vcpu_put(vcpu); + + elr = __vcpu_sys_reg(vcpu, ELR_EL2); + + trace_kvm_nested_eret(vcpu, elr, spsr); + + /* + * Note that the current exception level is always the virtual EL2, + * since we set HCR_EL2.NV bit only when entering the virtual EL2. + */ + *vcpu_pc(vcpu) = elr; + *vcpu_cpsr(vcpu) = spsr; + + kvm_arch_vcpu_load(vcpu, smp_processor_id()); + preempt_enable(); +} + +static void kvm_inject_el2_exception(struct kvm_vcpu *vcpu, u64 esr_el2, + enum exception_type type) +{ + trace_kvm_inject_nested_exception(vcpu, esr_el2, type); + + switch (type) { + case except_type_sync: + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_ELx_SYNC; + break; + case except_type_irq: + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_ELx_IRQ; + break; + default: + WARN_ONCE(1, "Unsupported EL2 exception injection %d\n", type); + } + + vcpu->arch.flags |= (KVM_ARM64_EXCEPT_AA64_EL2 | + KVM_ARM64_PENDING_EXCEPTION); + + vcpu_write_sys_reg(vcpu, esr_el2, ESR_EL2); +} + +/* + * Emulate taking an exception to EL2. + * See ARM ARM J8.1.2 AArch64.TakeException() + */ +static int kvm_inject_nested(struct kvm_vcpu *vcpu, u64 esr_el2, + enum exception_type type) +{ + u64 pstate, mode; + bool direct_inject; + + if (!nested_virt_in_use(vcpu)) { + kvm_err("Unexpected call to %s for the non-nesting configuration\n", + __func__); + return -EINVAL; + } + + /* + * As for ERET, we can avoid doing too much on the injection path by + * checking that we either took the exception from a VHE host + * userspace or from vEL2. In these cases, there is no change in + * translation regime (or anything else), so let's do as little as + * possible. + */ + pstate = *vcpu_cpsr(vcpu); + mode = pstate & (PSR_MODE_MASK | PSR_MODE32_BIT); + + direct_inject = (mode == PSR_MODE_EL0t && + vcpu_el2_e2h_is_set(vcpu) && + vcpu_el2_tge_is_set(vcpu)); + direct_inject |= (mode == PSR_MODE_EL2h || mode == PSR_MODE_EL2t); + + if (direct_inject) { + kvm_inject_el2_exception(vcpu, esr_el2, type); + return 1; + } + + preempt_disable(); + kvm_arch_vcpu_put(vcpu); + + kvm_inject_el2_exception(vcpu, esr_el2, type); + + /* + * A hard requirement is that a switch between EL1 and EL2 + * contexts has to happen between a put/load, so that we can + * pick the correct timer and interrupt configuration, among + * other things. + * + * Make sure the exception actually took place before we load + * the new context. + */ + __adjust_pc(vcpu); + + kvm_arch_vcpu_load(vcpu, smp_processor_id()); + preempt_enable(); + + return 1; +} + +int kvm_inject_nested_sync(struct kvm_vcpu *vcpu, u64 esr_el2) +{ + return kvm_inject_nested(vcpu, esr_el2, except_type_sync); +} + +int kvm_inject_nested_irq(struct kvm_vcpu *vcpu) +{ + /* + * Do not inject an irq if the: + * - Current exception level is EL2, and + * - virtual HCR_EL2.TGE == 0 + * - virtual HCR_EL2.IMO == 0 + * + * See Table D1-17 "Physical interrupt target and masking when EL3 is + * not implemented and EL2 is implemented" in ARM DDI 0487C.a. + */ + + if (vcpu_mode_el2(vcpu) && !vcpu_el2_tge_is_set(vcpu) && + !(__vcpu_sys_reg(vcpu, HCR_EL2) & HCR_IMO)) + return 1; + + /* esr_el2 value doesn't matter for exits due to irqs. */ + return kvm_inject_nested(vcpu, 0, except_type_irq); +} diff --git a/arch/arm64/kvm/hyp/exception.c b/arch/arm64/kvm/hyp/exception.c index 73629094f903..b6424c01a85a 100644 --- a/arch/arm64/kvm/hyp/exception.c +++ b/arch/arm64/kvm/hyp/exception.c @@ -13,6 +13,7 @@ #include #include #include +#include #if !defined (__KVM_NVHE_HYPERVISOR__) && !defined (__KVM_VHE_HYPERVISOR__) #error Hypervisor code only! @@ -22,7 +23,9 @@ static inline u64 __vcpu_read_sys_reg(const struct kvm_vcpu *vcpu, int reg) { u64 val; - if (__vcpu_read_sys_reg_from_cpu(reg, &val)) + if (unlikely(nested_virt_in_use(vcpu))) + return vcpu_read_sys_reg(vcpu, reg); + else if (__vcpu_read_sys_reg_from_cpu(reg, &val)) return val; return __vcpu_sys_reg(vcpu, reg); @@ -30,14 +33,26 @@ static inline u64 __vcpu_read_sys_reg(const struct kvm_vcpu *vcpu, int reg) static inline void __vcpu_write_sys_reg(struct kvm_vcpu *vcpu, u64 val, int reg) { - if (__vcpu_write_sys_reg_to_cpu(val, reg)) + if (unlikely(nested_virt_in_use(vcpu))) + vcpu_write_sys_reg(vcpu, val, reg); + else if (__vcpu_write_sys_reg_to_cpu(val, reg)) return; __vcpu_sys_reg(vcpu, reg) = val; } -static void __vcpu_write_spsr(struct kvm_vcpu *vcpu, u64 val) +static void __vcpu_write_spsr(struct kvm_vcpu *vcpu, unsigned long target_mode, + u64 val) { + if (unlikely(nested_virt_in_use(vcpu))) { + if (target_mode == PSR_MODE_EL1h) + vcpu_write_sys_reg(vcpu, val, SPSR_EL1); + else + vcpu_write_sys_reg(vcpu, val, SPSR_EL2); + + return; + } + write_sysreg_el1(val, SYS_SPSR); } @@ -97,6 +112,11 @@ static void enter_exception64(struct kvm_vcpu *vcpu, unsigned long target_mode, sctlr = __vcpu_read_sys_reg(vcpu, SCTLR_EL1); __vcpu_write_sys_reg(vcpu, *vcpu_pc(vcpu), ELR_EL1); break; + case PSR_MODE_EL2h: + vbar = __vcpu_read_sys_reg(vcpu, VBAR_EL2); + sctlr = __vcpu_read_sys_reg(vcpu, SCTLR_EL2); + __vcpu_write_sys_reg(vcpu, *vcpu_pc(vcpu), ELR_EL2); + break; default: /* Don't do that */ BUG(); @@ -148,7 +168,7 @@ static void enter_exception64(struct kvm_vcpu *vcpu, unsigned long target_mode, new |= target_mode; *vcpu_cpsr(vcpu) = new; - __vcpu_write_spsr(vcpu, old); + __vcpu_write_spsr(vcpu, target_mode, old); } /* @@ -319,11 +339,22 @@ void kvm_inject_exception(struct kvm_vcpu *vcpu) KVM_ARM64_EXCEPT_AA64_EL1): enter_exception64(vcpu, PSR_MODE_EL1h, except_type_sync); break; + + case (KVM_ARM64_EXCEPT_AA64_ELx_SYNC | + KVM_ARM64_EXCEPT_AA64_EL2): + enter_exception64(vcpu, PSR_MODE_EL2h, except_type_sync); + break; + + case (KVM_ARM64_EXCEPT_AA64_ELx_IRQ | + KVM_ARM64_EXCEPT_AA64_EL2): + enter_exception64(vcpu, PSR_MODE_EL2h, except_type_irq); + break; + default: /* - * Only EL1_SYNC makes sense so far, EL2_{SYNC,IRQ} - * will be implemented at some point. Everything - * else gets silently ignored. + * Only EL1_SYNC and EL2_{SYNC,IRQ} makes + * sense so far. Everything else gets silently + * ignored. */ break; } diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c index b47df73e98d7..06df0bb848ca 100644 --- a/arch/arm64/kvm/inject_fault.c +++ b/arch/arm64/kvm/inject_fault.c @@ -12,19 +12,53 @@ #include #include +#include #include +static void pend_sync_exception(struct kvm_vcpu *vcpu) +{ + vcpu->arch.flags |= (KVM_ARM64_EXCEPT_AA64_ELx_SYNC | + KVM_ARM64_PENDING_EXCEPTION); + + /* If not nesting, EL1 is the only possible exception target */ + if (likely(!nested_virt_in_use(vcpu))) { + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_EL1; + return; + } + + /* + * With NV, we need to pick between EL1 and EL2. Note that we + * never deal with a nesting exception here, hence never + * changing context, and the exception itself can be delayed + * until the next entry. + */ + switch(*vcpu_cpsr(vcpu) & PSR_MODE_MASK) { + case PSR_MODE_EL2h: + case PSR_MODE_EL2t: + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_EL2; + break; + case PSR_MODE_EL1h: + case PSR_MODE_EL1t: + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_EL1; + break; + case PSR_MODE_EL0t: + if (vcpu_el2_tge_is_set(vcpu) & HCR_TGE) + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_EL2; + else + vcpu->arch.flags |= KVM_ARM64_EXCEPT_AA64_EL1; + break; + default: + BUG(); + } +} + static void inject_abt64(struct kvm_vcpu *vcpu, bool is_iabt, unsigned long addr) { unsigned long cpsr = *vcpu_cpsr(vcpu); bool is_aarch32 = vcpu_mode_is_32bit(vcpu); u32 esr = 0; - vcpu->arch.flags |= (KVM_ARM64_EXCEPT_AA64_EL1 | - KVM_ARM64_EXCEPT_AA64_ELx_SYNC | - KVM_ARM64_PENDING_EXCEPTION); - - vcpu_write_sys_reg(vcpu, addr, FAR_EL1); + pend_sync_exception(vcpu); /* * Build an {i,d}abort, depending on the level and the @@ -45,16 +79,22 @@ static void inject_abt64(struct kvm_vcpu *vcpu, bool is_iabt, unsigned long addr if (!is_iabt) esr |= ESR_ELx_EC_DABT_LOW << ESR_ELx_EC_SHIFT; - vcpu_write_sys_reg(vcpu, esr | ESR_ELx_FSC_EXTABT, ESR_EL1); + esr |= ESR_ELx_FSC_EXTABT; + + if (vcpu->arch.flags & KVM_ARM64_EXCEPT_AA64_EL1) { + vcpu_write_sys_reg(vcpu, addr, FAR_EL1); + vcpu_write_sys_reg(vcpu, esr, ESR_EL1); + } else { + vcpu_write_sys_reg(vcpu, addr, FAR_EL2); + vcpu_write_sys_reg(vcpu, esr, ESR_EL2); + } } static void inject_undef64(struct kvm_vcpu *vcpu) { u32 esr = (ESR_ELx_EC_UNKNOWN << ESR_ELx_EC_SHIFT); - vcpu->arch.flags |= (KVM_ARM64_EXCEPT_AA64_EL1 | - KVM_ARM64_EXCEPT_AA64_ELx_SYNC | - KVM_ARM64_PENDING_EXCEPTION); + pend_sync_exception(vcpu); /* * Build an unknown exception, depending on the instruction @@ -63,7 +103,10 @@ static void inject_undef64(struct kvm_vcpu *vcpu) if (kvm_vcpu_trap_il_is32bit(vcpu)) esr |= ESR_ELx_IL; - vcpu_write_sys_reg(vcpu, esr, ESR_EL1); + if (vcpu->arch.flags & KVM_ARM64_EXCEPT_AA64_EL1) + vcpu_write_sys_reg(vcpu, esr, ESR_EL1); + else + vcpu_write_sys_reg(vcpu, esr, ESR_EL2); } #define DFSR_FSC_EXTABT_LPAE 0x10 diff --git a/arch/arm64/kvm/trace_arm.h b/arch/arm64/kvm/trace_arm.h index 33e4e7dd2719..f3e46a976125 100644 --- a/arch/arm64/kvm/trace_arm.h +++ b/arch/arm64/kvm/trace_arm.h @@ -2,6 +2,7 @@ #if !defined(_TRACE_ARM_ARM64_KVM_H) || defined(TRACE_HEADER_MULTI_READ) #define _TRACE_ARM_ARM64_KVM_H +#include #include #include @@ -301,6 +302,64 @@ TRACE_EVENT(kvm_timer_emulate, __entry->timer_idx, __entry->should_fire) ); +TRACE_EVENT(kvm_nested_eret, + TP_PROTO(struct kvm_vcpu *vcpu, unsigned long elr_el2, + unsigned long spsr_el2), + TP_ARGS(vcpu, elr_el2, spsr_el2), + + TP_STRUCT__entry( + __field(struct kvm_vcpu *, vcpu) + __field(unsigned long, elr_el2) + __field(unsigned long, spsr_el2) + __field(unsigned long, target_mode) + __field(unsigned long, hcr_el2) + ), + + TP_fast_assign( + __entry->vcpu = vcpu; + __entry->elr_el2 = elr_el2; + __entry->spsr_el2 = spsr_el2; + __entry->target_mode = spsr_el2 & (PSR_MODE_MASK | PSR_MODE32_BIT); + __entry->hcr_el2 = __vcpu_sys_reg(vcpu, HCR_EL2); + ), + + TP_printk("elr_el2: 0x%lx spsr_el2: 0x%08lx (M: %s) hcr_el2: %lx", + __entry->elr_el2, __entry->spsr_el2, + __print_symbolic(__entry->target_mode, kvm_mode_names), + __entry->hcr_el2) +); + +TRACE_EVENT(kvm_inject_nested_exception, + TP_PROTO(struct kvm_vcpu *vcpu, u64 esr_el2, int type), + TP_ARGS(vcpu, esr_el2, type), + + TP_STRUCT__entry( + __field(struct kvm_vcpu *, vcpu) + __field(unsigned long, esr_el2) + __field(int, type) + __field(unsigned long, spsr_el2) + __field(unsigned long, pc) + __field(unsigned long, source_mode) + __field(unsigned long, hcr_el2) + ), + + TP_fast_assign( + __entry->vcpu = vcpu; + __entry->esr_el2 = esr_el2; + __entry->type = type; + __entry->spsr_el2 = *vcpu_cpsr(vcpu); + __entry->pc = *vcpu_pc(vcpu); + __entry->source_mode = *vcpu_cpsr(vcpu) & (PSR_MODE_MASK | PSR_MODE32_BIT); + __entry->hcr_el2 = __vcpu_sys_reg(vcpu, HCR_EL2); + ), + + TP_printk("%s: esr_el2 0x%lx elr_el2: 0x%lx spsr_el2: 0x%08lx (M: %s) hcr_el2: %lx", + __print_symbolic(__entry->type, kvm_exception_type_names), + __entry->esr_el2, __entry->pc, __entry->spsr_el2, + __print_symbolic(__entry->source_mode, kvm_mode_names), + __entry->hcr_el2) +); + #endif /* _TRACE_ARM_ARM64_KVM_H */ #undef TRACE_INCLUDE_PATH -- 2.29.2 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel