From: Jintack Lim <[email protected]> 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 <[email protected]> Signed-off-by: Marc Zyngier <[email protected]> --- arch/arm64/include/asm/kvm_nested.h | 2 ++ arch/arm64/kvm/Makefile | 2 +- arch/arm64/kvm/handle_exit.c | 11 +++++++- arch/arm64/kvm/nested.c | 40 +++++++++++++++++++++++++++++ 4 files changed, 53 insertions(+), 2 deletions(-) create mode 100644 arch/arm64/kvm/nested.c diff --git a/arch/arm64/include/asm/kvm_nested.h b/arch/arm64/include/asm/kvm_nested.h index 67a2c0d05233..4c2ac9650a3e 100644 --- a/arch/arm64/include/asm/kvm_nested.h +++ b/arch/arm64/include/asm/kvm_nested.h @@ -61,4 +61,6 @@ static inline u64 translate_cnthctl_el2_to_cntkctl_el1(u64 cnthctl) (cnthctl & (CNTHCTL_EVNTI | CNTHCTL_EVNTDIR | CNTHCTL_EVNTEN))); } +int handle_wfx_nested(struct kvm_vcpu *vcpu, bool is_wfe); + #endif /* __ARM64_KVM_NESTED_H */ diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index ebf6ddb3cd77..598526c064f7 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 emulate-nested.o \ + arch_timer.o trng.o emulate-nested.o 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/handle_exit.c b/arch/arm64/kvm/handle_exit.c index f0fc99c7c9ca..2f579152df0b 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -119,7 +119,16 @@ static int handle_no_fpsimd(struct kvm_vcpu *vcpu) */ static int kvm_handle_wfx(struct kvm_vcpu *vcpu) { - if (kvm_vcpu_get_esr(vcpu) & ESR_ELx_WFx_ISS_WFE) { + bool is_wfe = !!(kvm_vcpu_get_esr(vcpu) & ESR_ELx_WFx_ISS_WFE); + + if (nested_virt_in_use(vcpu)) { + int ret = handle_wfx_nested(vcpu, is_wfe); + + if (ret != -EINVAL) + return ret; + } + + if (is_wfe) { trace_kvm_wfx_arm64(*vcpu_pc(vcpu), true); vcpu->stat.wfe_exit_stat++; kvm_vcpu_on_spin(vcpu, vcpu_mode_priv(vcpu)); diff --git a/arch/arm64/kvm/nested.c b/arch/arm64/kvm/nested.c new file mode 100644 index 000000000000..42a96c8d2adc --- /dev/null +++ b/arch/arm64/kvm/nested.c @@ -0,0 +1,40 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2017 - Columbia University and Linaro Ltd. + * Author: Jintack Lim <[email protected]> + * + * 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 <http://www.gnu.org/licenses/>. + */ + +#include <linux/kvm.h> +#include <linux/kvm_host.h> + +#include <asm/kvm_emulate.h> + +/* + * 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_esr(vcpu)); + + return -EINVAL; +} -- 2.29.2 _______________________________________________ kvmarm mailing list [email protected] https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
