Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751500AbdFFWHM (ORCPT ); Tue, 6 Jun 2017 18:07:12 -0400 Received: from mx1.redhat.com ([209.132.183.28]:36486 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751401AbdFFWHK (ORCPT ); Tue, 6 Jun 2017 18:07:10 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 0D0F885545 Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=bsd@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 0D0F885545 From: Bandan Das To: Jintack Lim Cc: KVM General , Catalin Marinas , Will Deacon , kvmarm@lists.cs.columbia.edu, Shih-Wei Li , lorenzo.pieralisi@arm.com, linux@armlinux.org.uk, arm-mail-list , Marc Zyngier , Andre Przywara , kevin.brodsky@arm.com, wcohen@redhat.com, anna-maria@linutronix.de, geoff@infradead.org, lkml - Kernel Mailing List , Paolo Bonzini , Jintack Lim Subject: Re: [RFC 11/55] KVM: arm64: Emulate taking an exception to the guest hypervisor References: <1483943091-1364-1-git-send-email-jintack@cs.columbia.edu> <1483943091-1364-12-git-send-email-jintack@cs.columbia.edu> Date: Tue, 06 Jun 2017 18:07:07 -0400 In-Reply-To: (Jintack Lim's message of "Tue, 6 Jun 2017 16:38:56 -0400") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Tue, 06 Jun 2017 22:07:10 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7289 Lines: 202 Hi Jintack, Jintack Lim writes: > Hi Bandan, > > On Tue, Jun 6, 2017 at 4:21 PM, Bandan Das wrote: >> Jintack Lim writes: >> >>> Emulate taking an exception to the guest hypervisor running in the >>> virtual EL2 as described in ARM ARM AArch64.TakeException(). >> >> ARM newbie here, I keep thinking of ARM ARM as a typo ;) > > ARM ARM means ARM Architecture Reference Manual :) > >> ... >>> +static inline int kvm_inject_nested_sync(struct kvm_vcpu *vcpu, u64 esr_el2) >>> +{ >>> + kvm_err("Unexpected call to %s for the non-nesting configuration\n", >>> + __func__); >>> + return -EINVAL; >>> +} >>> + >>> +static inline int kvm_inject_nested_irq(struct kvm_vcpu *vcpu) >>> +{ >>> + kvm_err("Unexpected call to %s for the non-nesting configuration\n", >>> + __func__); >>> + return -EINVAL; >>> +} >>> + >> >> I see these function stubs for aarch32 in the patches. I don't see how they >> can actually be called though. Is this because eventually, there will be >> a virtual el2 mode for aarch32 ? > > Current RFC doesn't support nested virtualization on 32bit arm > architecture and those functions will be never called. Those functions > are there for the compilation. Do you mean that compilation will fail ? It seems these functions are defined separately in 32/64 bit specific header files. Or is it that 64 bit compilation also depends on the 32 bit header file ? Bandan > Thanks, > Jintack > >> >> Bandan >> >>> static inline void kvm_arm_setup_shadow_state(struct kvm_vcpu *vcpu) { }; >>> static inline void kvm_arm_restore_shadow_state(struct kvm_vcpu *vcpu) { }; >>> static inline void kvm_arm_init_cpu_context(kvm_cpu_context_t *cpu_ctxt) { }; >>> diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h >>> index 8892c82..0987ee4 100644 >>> --- a/arch/arm64/include/asm/kvm_emulate.h >>> +++ b/arch/arm64/include/asm/kvm_emulate.h >>> @@ -42,6 +42,25 @@ >>> void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr); >>> void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr); >>> >>> +#ifdef CONFIG_KVM_ARM_NESTED_HYP >>> +int kvm_inject_nested_sync(struct kvm_vcpu *vcpu, u64 esr_el2); >>> +int kvm_inject_nested_irq(struct kvm_vcpu *vcpu); >>> +#else >>> +static inline int kvm_inject_nested_sync(struct kvm_vcpu *vcpu, u64 esr_el2) >>> +{ >>> + kvm_err("Unexpected call to %s for the non-nesting configuration\n", >>> + __func__); >>> + return -EINVAL; >>> +} >>> + >>> +static inline int kvm_inject_nested_irq(struct kvm_vcpu *vcpu) >>> +{ >>> + kvm_err("Unexpected call to %s for the non-nesting configuration\n", >>> + __func__); >>> + return -EINVAL; >>> +} >>> +#endif >>> + >>> void kvm_arm_setup_shadow_state(struct kvm_vcpu *vcpu); >>> void kvm_arm_restore_shadow_state(struct kvm_vcpu *vcpu); >>> void kvm_arm_init_cpu_context(kvm_cpu_context_t *cpu_ctxt); >>> diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile >>> index 7811d27..b342bdd 100644 >>> --- a/arch/arm64/kvm/Makefile >>> +++ b/arch/arm64/kvm/Makefile >>> @@ -34,3 +34,5 @@ kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic/vgic-its.o >>> kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/irqchip.o >>> kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/arch_timer.o >>> kvm-$(CONFIG_KVM_ARM_PMU) += $(KVM)/arm/pmu.o >>> + >>> +kvm-$(CONFIG_KVM_ARM_NESTED_HYP) += emulate-nested.o >>> diff --git a/arch/arm64/kvm/emulate-nested.c b/arch/arm64/kvm/emulate-nested.c >>> new file mode 100644 >>> index 0000000..59d147f >>> --- /dev/null >>> +++ b/arch/arm64/kvm/emulate-nested.c >>> @@ -0,0 +1,66 @@ >>> +/* >>> + * Copyright (C) 2016 - 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 "trace.h" >>> + >>> +#define EL2_EXCEPT_SYNC_OFFSET 0x400 >>> +#define EL2_EXCEPT_ASYNC_OFFSET 0x480 >>> + >>> + >>> +/* >>> + * Emulate taking an exception. See ARM ARM J8.1.2 AArch64.TakeException() >>> + */ >>> +static int kvm_inject_nested(struct kvm_vcpu *vcpu, u64 esr_el2, >>> + int exception_offset) >>> +{ >>> + int ret = 1; >>> + kvm_cpu_context_t *ctxt = &vcpu->arch.ctxt; >>> + >>> + /* We don't inject an exception recursively to virtual EL2 */ >>> + if (vcpu_mode_el2(vcpu)) >>> + BUG(); >>> + >>> + ctxt->el2_regs[SPSR_EL2] = *vcpu_cpsr(vcpu); >>> + ctxt->el2_regs[ELR_EL2] = *vcpu_pc(vcpu); >>> + ctxt->el2_regs[ESR_EL2] = esr_el2; >>> + >>> + /* On an exception, PSTATE.SP = 1 */ >>> + *vcpu_cpsr(vcpu) = PSR_MODE_EL2h; >>> + *vcpu_cpsr(vcpu) |= (PSR_A_BIT | PSR_F_BIT | PSR_I_BIT | PSR_D_BIT); >>> + *vcpu_pc(vcpu) = ctxt->el2_regs[VBAR_EL2] + exception_offset; >>> + >>> + trace_kvm_inject_nested_exception(vcpu, esr_el2, *vcpu_pc(vcpu)); >>> + >>> + return ret; >>> +} >>> + >>> +int kvm_inject_nested_sync(struct kvm_vcpu *vcpu, u64 esr_el2) >>> +{ >>> + return kvm_inject_nested(vcpu, esr_el2, EL2_EXCEPT_SYNC_OFFSET); >>> +} >>> + >>> +int kvm_inject_nested_irq(struct kvm_vcpu *vcpu) >>> +{ >>> + u64 esr_el2 = kvm_vcpu_get_hsr(vcpu); >>> + /* We supports only IRQ and FIQ, so the esr_el2 is not updated. */ >>> + return kvm_inject_nested(vcpu, esr_el2, EL2_EXCEPT_ASYNC_OFFSET); >>> +} >>> diff --git a/arch/arm64/kvm/trace.h b/arch/arm64/kvm/trace.h >>> index 7fb0008..7c86cfb 100644 >>> --- a/arch/arm64/kvm/trace.h >>> +++ b/arch/arm64/kvm/trace.h >>> @@ -167,6 +167,26 @@ >>> ); >>> >>> >>> +TRACE_EVENT(kvm_inject_nested_exception, >>> + TP_PROTO(struct kvm_vcpu *vcpu, unsigned long esr_el2, >>> + unsigned long pc), >>> + TP_ARGS(vcpu, esr_el2, pc), >>> + >>> + TP_STRUCT__entry( >>> + __field(struct kvm_vcpu *, vcpu) >>> + __field(unsigned long, esr_el2) >>> + __field(unsigned long, pc) >>> + ), >>> + >>> + TP_fast_assign( >>> + __entry->vcpu = vcpu; >>> + __entry->esr_el2 = esr_el2; >>> + __entry->pc = pc; >>> + ), >>> + >>> + TP_printk("vcpu: %p, inject exception to vEL2: ESR_EL2 0x%lx, vector: 0x%016lx", >>> + __entry->vcpu, __entry->esr_el2, __entry->pc) >>> +); >>> #endif /* _TRACE_ARM64_KVM_H */ >>> >>> #undef TRACE_INCLUDE_PATH >> _______________________________________________ >> kvmarm mailing list >> kvmarm@lists.cs.columbia.edu >> https://lists.cs.columbia.edu/mailman/listinfo/kvmarm