Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752468AbdGRRFW (ORCPT ); Tue, 18 Jul 2017 13:05:22 -0400 Received: from mail-io0-f175.google.com ([209.85.223.175]:36469 "EHLO mail-io0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752271AbdGRRAS (ORCPT ); Tue, 18 Jul 2017 13:00:18 -0400 From: Jintack Lim To: kvmarm@lists.cs.columbia.edu, christoffer.dall@linaro.org, marc.zyngier@arm.com Cc: corbet@lwn.net, pbonzini@redhat.com, rkrcmar@redhat.com, linux@armlinux.org.uk, catalin.marinas@arm.com, will.deacon@arm.com, akpm@linux-foundation.org, mchehab@kernel.org, cov@codeaurora.org, daniel.lezcano@linaro.org, david.daney@cavium.com, mark.rutland@arm.com, suzuki.poulose@arm.com, stefan@hello-penguin.com, andy.gross@linaro.org, wcohen@redhat.com, ard.biesheuvel@linaro.org, shankerd@codeaurora.org, vladimir.murzin@arm.com, james.morse@arm.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Jintack Lim Subject: [RFC PATCH v2 24/38] KVM: arm64: Respect virtual HCR_EL2.TWX setting Date: Tue, 18 Jul 2017 11:58:50 -0500 Message-Id: <1500397144-16232-25-git-send-email-jintack.lim@linaro.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1500397144-16232-1-git-send-email-jintack.lim@linaro.org> References: <1500397144-16232-1-git-send-email-jintack.lim@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2563 Lines: 82 Forward exceptions due to WFI or WFE instructions to the virtual EL2 if they are not coming from the virtual EL2 and virtual HCR_EL2.TWX is set. Signed-off-by: Jintack Lim --- arch/arm64/include/asm/kvm_host.h | 1 + arch/arm64/kvm/handle_exit.c | 13 ++++++++++++- arch/arm64/kvm/nested.c | 20 ++++++++++++++++++++ 3 files changed, 33 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 46880c3..53b0b33 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -442,5 +442,6 @@ static inline void __cpu_init_stage2(void) int __init kvmarm_nested_cfg(char *buf); int init_nested_virt(void); bool nested_virt_in_use(struct kvm_vcpu *vcpu); +int handle_wfx_nested(struct kvm_vcpu *vcpu, bool is_wfe); #endif /* __ARM64_KVM_HOST_H__ */ diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index 8b398b2..25ec824 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -107,7 +107,18 @@ static int handle_no_fpsimd(struct kvm_vcpu *vcpu, struct kvm_run *run) */ static int kvm_handle_wfx(struct kvm_vcpu *vcpu, struct kvm_run *run) { - if (kvm_vcpu_get_hsr(vcpu) & ESR_ELx_WFx_ISS_WFE) { + bool is_wfe = !!(kvm_vcpu_get_hsr(vcpu) & ESR_ELx_WFx_ISS_WFE); + + if (nested_virt_in_use(vcpu)) { + int ret = handle_wfx_nested(vcpu, is_wfe); + + if (ret < 0 && ret != -EINVAL) + return ret; + else if (ret >= 0) + return ret; + } + + if (is_wfe) { trace_kvm_wfx_arm64(*vcpu_pc(vcpu), true); vcpu->stat.wfe_exit_stat++; kvm_vcpu_on_spin(vcpu); diff --git a/arch/arm64/kvm/nested.c b/arch/arm64/kvm/nested.c index 9a05c76..042d304 100644 --- a/arch/arm64/kvm/nested.c +++ b/arch/arm64/kvm/nested.c @@ -18,6 +18,8 @@ #include #include +#include + static bool nested_param; int __init kvmarm_nested_cfg(char *buf) @@ -41,3 +43,21 @@ bool nested_virt_in_use(struct kvm_vcpu *vcpu) return false; } + +/* + * Inject wfx to the virtual EL2 if this is not from the virtual EL2 and + * the virtual HCR_EL2.TWX is set. Otherwise, let the host hypervisor + * handle this. + */ +int handle_wfx_nested(struct kvm_vcpu *vcpu, bool is_wfe) +{ + u64 hcr_el2 = vcpu_sys_reg(vcpu, HCR_EL2); + + if (vcpu_mode_el2(vcpu)) + return -EINVAL; + + if ((is_wfe && (hcr_el2 & HCR_TWE)) || (!is_wfe && (hcr_el2 & HCR_TWI))) + return kvm_inject_nested_sync(vcpu, kvm_vcpu_get_hsr(vcpu)); + + return -EINVAL; +} -- 1.9.1