| Message ID | 1500397144-16232-25-git-send-email-jintack.lim@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Jul 18, 2017 at 11:58:50AM -0500, Jintack Lim wrote: > 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> > --- > 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; This is very complicated and you're not documenting the return value of handle_wfx_nested. If you get rid of the defensive statement in kvm_inject_nested, you can turn that one into a void, and handle_wfx_nested can become a bool, and then this becomes: if (ret) return 1; If for some reason you don't like that, you can still just do: if (ret == 1) return 1; > + } > + > + 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 <linux/kvm.h> > #include <linux/kvm_host.h> > > +#include <asm/kvm_emulate.h> > + > 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 >
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 <linux/kvm.h> #include <linux/kvm_host.h> +#include <asm/kvm_emulate.h> + 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; +}
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> --- 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(-)