// Deal with L2 EPT violation VM-exit.
_Use_decl_annotations_ void EptHandleEptViolationEx(EptData *ept_data, EptData *ept_data02, ULONG_PTR guest_pa, bool is_range_of_ept12) {
const EptViolationQualification exit_qualification = {
UtilVmRead(VmcsField::kExitQualification) };
ULONG_PTR fault_pa = 0;
if (!guest_pa)
{
fault_pa = UtilVmRead64(VmcsField::kGuestPhysicalAddress);
}
else
{
fault_pa = guest_pa;
}
const auto fault_va = reinterpret_cast<void *>(
exit_qualification.fields.valid_guest_linear_address
? UtilVmRead(VmcsField::kGuestLinearAddress)
: 0);
//GuestPhysicalAddress will be the guest physical adderss of EPT1-2 Entry , we disable it write in L2 first initial
if (!exit_qualification.fields.ept_readable &&
!exit_qualification.fields.ept_writeable &&
!exit_qualification.fields.ept_executable) {
const auto ept_entry = EptGetEptPtEntry(ept_data, fault_pa);
if (!ept_entry || !ept_entry->all) {
// EPT entry miss. It should be device memory.
HYPERPLATFORM_PERFORMANCE_MEASURE_THIS_SCOPE();
if (!IsReleaseBuild()) {
NT_VERIFY(EptpIsDeviceMemory(fault_pa));
}
EptpConstructTables(ept_data->ept_pml4, 4, fault_pa, ept_data);
UtilInveptGlobal();
return;
}
}
if (!exit_qualification.fields.ept_writeable && is_range_of_ept12)
{
EptCommonEntry* Ept01Pte = EptGetEptPtEntry(ept_data, UtilVmRead64(VmcsField::kGuestPhysicalAddress));
if (Ept01Pte)
{
EptCommonEntry* entry = (EptCommonEntry*)UtilVaFromPa(UtilVmRead64(VmcsField::kGuestPhysicalAddress));
Ept01Pte->fields.write_access = true;
HYPERPLATFORM_LOG_DEBUG_SAFE("Faced non-writable address but it is readble. :%p %p", UtilVmRead64(VmcsField::kGuestPhysicalAddress), entry->fields.physial_address);
UtilInveptGlobal();
}
}
}
// See: VMM SETUP & TEAR DOWN
_Use_decl_annotations_ static bool VmpEnterVmxMode(
ProcessorData *processor_data) {
PAGED_CODE();
// Apply FIXED bits
// See: VMX-FIXED BITS IN CR0
// IA32_VMX_CRx_FIXED0 IA32_VMX_CRx_FIXED1 Meaning
// Values 1 1 bit of CRx is fixed to 1
// Values 0 1 bit of CRx is flexible
// Values 0 0 bit of CRx is fixed to 0
const Cr0 cr0_fixed0 = {UtilReadMsr(Msr::kIa32VmxCr0Fixed0)};
const Cr0 cr0_fixed1 = {UtilReadMsr(Msr::kIa32VmxCr0Fixed1)};
Cr0 cr0 = {__readcr0()};
Cr0 cr0_original = cr0;
cr0.all &= cr0_fixed1.all;
cr0.all |= cr0_fixed0.all;
__writecr0(cr0.all);
HYPERPLATFORM_LOG_DEBUG("IA32_VMX_CR0_FIXED0 = %08x", cr0_fixed0.all);
HYPERPLATFORM_LOG_DEBUG("IA32_VMX_CR0_FIXED1 = %08x", cr0_fixed1.all);
HYPERPLATFORM_LOG_DEBUG("Original CR0 = %08x", cr0_original.all);
HYPERPLATFORM_LOG_DEBUG("Fixed CR0 = %08x", cr0.all);
// See: VMX-FIXED BITS IN CR4
const Cr4 cr4_fixed0 = {UtilReadMsr(Msr::kIa32VmxCr4Fixed0)};
const Cr4 cr4_fixed1 = {UtilReadMsr(Msr::kIa32VmxCr4Fixed1)};
Cr4 cr4 = {__readcr4()};
Cr4 cr4_original = cr4;
cr4.all &= cr4_fixed1.all;
cr4.all |= cr4_fixed0.all;
__writecr4(cr4.all);
HYPERPLATFORM_LOG_DEBUG("IA32_VMX_CR4_FIXED0 = %08x", cr4_fixed0.all);
HYPERPLATFORM_LOG_DEBUG("IA32_VMX_CR4_FIXED1 = %08x", cr4_fixed1.all);
HYPERPLATFORM_LOG_DEBUG("Original CR4 = %08x", cr4_original.all);
HYPERPLATFORM_LOG_DEBUG("Fixed CR4 = %08x", cr4.all);
// Write a VMCS revision identifier
const Ia32VmxBasicMsr vmx_basic_msr = {UtilReadMsr64(Msr::kIa32VmxBasic)};
processor_data->vmxon_region->revision_identifier =
vmx_basic_msr.fields.revision_identifier;
auto vmxon_region_pa = UtilPaFromVa(processor_data->vmxon_region);
if (__vmx_on(&vmxon_region_pa)) {
return false;
}
// See: Guidelines for Use of the INVVPID Instruction, and Guidelines for Use
// of the INVEPT Instruction
UtilInveptGlobal();
UtilInvvpidAllContext();
return true;
}
