diff options
| -rw-r--r-- | sys/arch/amd64/amd64/vmm.c | 109 |
1 files changed, 108 insertions, 1 deletions
diff --git a/sys/arch/amd64/amd64/vmm.c b/sys/arch/amd64/amd64/vmm.c index 27d46b65c4f..e146c7fa7c0 100644 --- a/sys/arch/amd64/amd64/vmm.c +++ b/sys/arch/amd64/amd64/vmm.c @@ -1,4 +1,4 @@ -/* $OpenBSD: vmm.c,v 1.205 2018/07/02 05:37:18 mlarkin Exp $ */ +/* $OpenBSD: vmm.c,v 1.206 2018/07/05 03:48:45 mlarkin Exp $ */ /* * Copyright (c) 2014 Mike Larkin <mlarkin@openbsd.org> * @@ -175,6 +175,8 @@ int vmm_get_guest_faulttype(void); int vmx_get_guest_faulttype(void); int svm_get_guest_faulttype(struct vmcb *); int vmx_get_exit_qualification(uint64_t *); +int vmm_get_guest_cpu_cpl(struct vcpu *); +int vmm_get_guest_cpu_mode(struct vcpu *); int svm_fault_page(struct vcpu *, paddr_t); int vmx_fault_page(struct vcpu *, paddr_t); int vmx_handle_np_fault(struct vcpu *); @@ -4894,6 +4896,111 @@ vmx_handle_np_fault(struct vcpu *vcpu) } /* + * vmm_get_guest_cpu_cpl + * + * Determines current CPL of 'vcpu'. On VMX/Intel, this is gathered from the + * VMCS field for the DPL of SS (this seems odd, but is documented that way + * in the SDM). For SVM/AMD, this is gathered directly from the VMCB's 'cpl' + * field, as per the APM. + * + * Parameters: + * vcpu: guest VCPU for which CPL is to be checked + * + * Return Values: + * -1: the CPL could not be determined + * 0-3 indicating the current CPL. For real mode operation, 0 is returned. + */ +int +vmm_get_guest_cpu_cpl(struct vcpu *vcpu) +{ + int mode; + struct vmcb *vmcb; + uint64_t ss_ar; + + mode = vmm_get_guest_cpu_mode(vcpu); + + if (mode == VMM_CPU_MODE_UNKNOWN) + return (-1); + + if (mode == VMM_CPU_MODE_REAL) + return (0); + + if (vmm_softc->mode == VMM_MODE_SVM || + vmm_softc->mode == VMM_MODE_RVI) { + vmcb = (struct vmcb *)vcpu->vc_control_va; + return (vmcb->v_cpl); + } else if (vmm_softc->mode == VMM_MODE_VMX || + vmm_softc->mode == VMM_MODE_EPT) { + if (vmread(VMCS_GUEST_IA32_SS_AR, &ss_ar)) + return (-1); + return ((ss_ar & 0x60) >> 5); + } else + return (-1); +} + +/* + * vmm_get_guest_cpu_mode + * + * Determines current CPU mode of 'vcpu'. + * + * Parameters: + * vcpu: guest VCPU for which mode is to be checked + * + * Return Values: + * One of VMM_CPU_MODE_*, or VMM_CPU_MODE_UNKNOWN if the mode could not be + * ascertained. + */ +int +vmm_get_guest_cpu_mode(struct vcpu *vcpu) +{ + uint64_t cr0, efer, cs_ar; + uint8_t l, dib; + struct vmcb *vmcb; + struct vmx_msr_store *msr_store; + + if (vmm_softc->mode == VMM_MODE_SVM || + vmm_softc->mode == VMM_MODE_RVI) { + vmcb = (struct vmcb *)vcpu->vc_control_va; + cr0 = vmcb->v_cr0; + efer = vmcb->v_efer; + cs_ar = vmcb->v_cs.vs_attr; + cs_ar = (cs_ar & 0xff) | ((cs_ar << 4) & 0xf000); + } else if (vmm_softc->mode == VMM_MODE_VMX || + vmm_softc->mode == VMM_MODE_EPT) { + if (vmread(VMCS_GUEST_IA32_CR0, &cr0)) + return (VMM_CPU_MODE_UNKNOWN); + if (vmread(VMCS_GUEST_IA32_CS_AR, &cs_ar)) + return (VMM_CPU_MODE_UNKNOWN); + msr_store = + (struct vmx_msr_store *)vcpu->vc_vmx_msr_exit_save_va; + efer = msr_store[VCPU_REGS_EFER].vms_data; + } else + return (VMM_CPU_MODE_UNKNOWN); + + l = (cs_ar & 0x2000) >> 13; + dib = (cs_ar & 0x4000) >> 14; + + /* Check CR0.PE */ + if (!(cr0 & CR0_PE)) + return (VMM_CPU_MODE_REAL); + + /* Check EFER */ + if (efer & EFER_LMA) { + /* Could be compat or long mode, check CS.L */ + if (l) + return (VMM_CPU_MODE_LONG); + else + return (VMM_CPU_MODE_COMPAT); + } + + /* Check prot vs prot32 */ + if (dib) + return (VMM_CPU_MODE_PROT32); + else + return (VMM_CPU_MODE_PROT); +} + +/* * svm_handle_inout * * Exit handler for IN/OUT instructions. |