| Message ID | 20190621093843.220980-24-marc.zyngier@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: arm64: ARMv8.3 Nested Virtualization support | expand |
On 06/21/2019 10:38 AM, Marc Zyngier wrote: > From: Jintack Lim <jintack.lim@linaro.org> > > 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 <jintack.lim@linaro.org> > Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> > --- > arch/arm64/include/asm/kvm_nested.h | 2 ++ > arch/arm64/kvm/Makefile | 1 + > arch/arm64/kvm/handle_exit.c | 13 +++++++++- > arch/arm64/kvm/nested.c | 39 +++++++++++++++++++++++++++++ > 4 files changed, 54 insertions(+), 1 deletion(-) > 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 8a3d121a0b42..645e5e11b749 100644 > --- a/arch/arm64/include/asm/kvm_nested.h > +++ b/arch/arm64/include/asm/kvm_nested.h > @@ -10,4 +10,6 @@ static inline bool nested_virt_in_use(const struct kvm_vcpu *vcpu) > test_bit(KVM_ARM_VCPU_NESTED_VIRT, vcpu->arch.features); > } > > +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 9e450aea7db6..f11bd8b0d837 100644 > --- a/arch/arm64/kvm/Makefile > +++ b/arch/arm64/kvm/Makefile > @@ -36,4 +36,5 @@ 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_HOST) += nested.o > kvm-$(CONFIG_KVM_ARM_HOST) += emulate-nested.o > diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c > index e348c15c81bc..ddba212fd6ec 100644 > --- a/arch/arm64/kvm/handle_exit.c > +++ b/arch/arm64/kvm/handle_exit.c > @@ -127,7 +127,18 @@ 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; I think you can simplify this: if (ret != -EINVAL) return ret; Cheers, Julien > + } > + > + 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..3872e3cf1691 > --- /dev/null > +++ b/arch/arm64/kvm/nested.c > @@ -0,0 +1,39 @@ > +/* > + * Copyright (C) 2017 - Columbia University and Linaro Ltd. > + * Author: Jintack Lim <jintack.lim@linaro.org> > + * > + * 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_hsr(vcpu)); > + > + return -EINVAL; > +} >
On 6/25/19 3:19 PM, Julien Thierry wrote: > > On 06/21/2019 10:38 AM, Marc Zyngier wrote: >> From: Jintack Lim <jintack.lim@linaro.org> >> >> 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 <jintack.lim@linaro.org> >> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> >> --- >> arch/arm64/include/asm/kvm_nested.h | 2 ++ >> arch/arm64/kvm/Makefile | 1 + >> arch/arm64/kvm/handle_exit.c | 13 +++++++++- >> arch/arm64/kvm/nested.c | 39 +++++++++++++++++++++++++++++ >> 4 files changed, 54 insertions(+), 1 deletion(-) >> 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 8a3d121a0b42..645e5e11b749 100644 >> --- a/arch/arm64/include/asm/kvm_nested.h >> +++ b/arch/arm64/include/asm/kvm_nested.h >> @@ -10,4 +10,6 @@ static inline bool nested_virt_in_use(const struct kvm_vcpu *vcpu) >> test_bit(KVM_ARM_VCPU_NESTED_VIRT, vcpu->arch.features); >> } >> >> +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 9e450aea7db6..f11bd8b0d837 100644 >> --- a/arch/arm64/kvm/Makefile >> +++ b/arch/arm64/kvm/Makefile >> @@ -36,4 +36,5 @@ 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_HOST) += nested.o >> kvm-$(CONFIG_KVM_ARM_HOST) += emulate-nested.o >> diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c >> index e348c15c81bc..ddba212fd6ec 100644 >> --- a/arch/arm64/kvm/handle_exit.c >> +++ b/arch/arm64/kvm/handle_exit.c >> @@ -127,7 +127,18 @@ 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; > I think you can simplify this: > > if (ret != -EINVAL) > return ret; And handle_wfx_nested can only return -EINVAL or 1 (from kvm_inject_nested_sync), so the condition is not only complicated, but also misleading. Thanks, Alex > > Cheers, > > Julien > > >> + } >> + >> + 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..3872e3cf1691 >> --- /dev/null >> +++ b/arch/arm64/kvm/nested.c >> @@ -0,0 +1,39 @@ >> +/* >> + * Copyright (C) 2017 - Columbia University and Linaro Ltd. >> + * Author: Jintack Lim <jintack.lim@linaro.org> >> + * >> + * 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_hsr(vcpu)); >> + >> + return -EINVAL; >> +} >>
On 25/06/2019 15:19, Julien Thierry wrote: > > > On 06/21/2019 10:38 AM, Marc Zyngier wrote: >> From: Jintack Lim <jintack.lim@linaro.org> >> >> 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 <jintack.lim@linaro.org> >> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> >> --- >> arch/arm64/include/asm/kvm_nested.h | 2 ++ >> arch/arm64/kvm/Makefile | 1 + >> arch/arm64/kvm/handle_exit.c | 13 +++++++++- >> arch/arm64/kvm/nested.c | 39 +++++++++++++++++++++++++++++ >> 4 files changed, 54 insertions(+), 1 deletion(-) >> 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 8a3d121a0b42..645e5e11b749 100644 >> --- a/arch/arm64/include/asm/kvm_nested.h >> +++ b/arch/arm64/include/asm/kvm_nested.h >> @@ -10,4 +10,6 @@ static inline bool nested_virt_in_use(const struct kvm_vcpu *vcpu) >> test_bit(KVM_ARM_VCPU_NESTED_VIRT, vcpu->arch.features); >> } >> >> +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 9e450aea7db6..f11bd8b0d837 100644 >> --- a/arch/arm64/kvm/Makefile >> +++ b/arch/arm64/kvm/Makefile >> @@ -36,4 +36,5 @@ 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_HOST) += nested.o >> kvm-$(CONFIG_KVM_ARM_HOST) += emulate-nested.o >> diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c >> index e348c15c81bc..ddba212fd6ec 100644 >> --- a/arch/arm64/kvm/handle_exit.c >> +++ b/arch/arm64/kvm/handle_exit.c >> @@ -127,7 +127,18 @@ static int handle_no_fpsimd(struct kvm_vcpu *vcpu, struct kvm_run *run) >> */ >> static int kvm_handle_wfx(struct kvm_vcpu *vcpu, struct kvm_run *run) >> { >> - if (kvm_vcpu_get_hsr(vcpu) & ESR_ELx_WFx_ISS_WFE) { >> + bool is_wfe = !!(kvm_vcpu_get_hsr(vcpu) & ESR_ELx_WFx_ISS_WFE); >> + >> + if (nested_virt_in_use(vcpu)) { >> + int ret = handle_wfx_nested(vcpu, is_wfe); >> + >> + if (ret < 0 && ret != -EINVAL) >> + return ret; >> + else if (ret >= 0) >> + return ret; > > I think you can simplify this: > > if (ret != -EINVAL) > return ret; Ah! Yes. ;-) M.
diff --git a/arch/arm64/include/asm/kvm_nested.h b/arch/arm64/include/asm/kvm_nested.h index 8a3d121a0b42..645e5e11b749 100644 --- a/arch/arm64/include/asm/kvm_nested.h +++ b/arch/arm64/include/asm/kvm_nested.h @@ -10,4 +10,6 @@ static inline bool nested_virt_in_use(const struct kvm_vcpu *vcpu) test_bit(KVM_ARM_VCPU_NESTED_VIRT, vcpu->arch.features); } +int handle_wfx_nested(struct kvm_vcpu *vcpu, bool is_wfe); + #endif /* __ARM64_KVM_NESTED_H */ diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index 9e450aea7db6..f11bd8b0d837 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -36,4 +36,5 @@ kvm-$(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_HOST) += nested.o kvm-$(CONFIG_KVM_ARM_HOST) += emulate-nested.o diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index e348c15c81bc..ddba212fd6ec 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -127,7 +127,18 @@ 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, vcpu_mode_priv(vcpu)); diff --git a/arch/arm64/kvm/nested.c b/arch/arm64/kvm/nested.c new file mode 100644 index 000000000000..3872e3cf1691 --- /dev/null +++ b/arch/arm64/kvm/nested.c @@ -0,0 +1,39 @@ +/* + * Copyright (C) 2017 - Columbia University and Linaro Ltd. + * Author: Jintack Lim <jintack.lim@linaro.org> + * + * 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_hsr(vcpu)); + + return -EINVAL; +}