StmApi.h File Reference

Data Structures
struct	STM_FEAT
struct	SOFTWARE_STM_HEADER
struct	STM_HEADER
struct	STM_MAP_ADDRESS_RANGE_DESCRIPTOR
struct	STM_UNMAP_ADDRESS_RANGE_DESCRIPTOR
struct	STM_ADDRESS_LOOKUP_DESCRIPTOR
struct	STM_VMCS_DATABASE_REQUEST
struct	STM_EVENT_LOG_MANAGEMENT_REQUEST
struct	LOG_ENTRY_HEADER
struct	ENTRY_EVT_LOG_STARTED
struct	ENTRY_EVT_LOG_STOPPED
struct	ENTRY_EVT_LOG_INVALID_PARAM
struct	ENTRY_EVT_LOG_HANDLED_PROTECTION_EXCEPTION
struct	ENTRY_EVT_BIOS_ACCESS_UNCLAIMED_RSC
struct	ENTRY_EVT_MLE_RSC_PROT_GRANTED
struct	ENTRY_EVT_MLE_RSC_PROT_DENIED
struct	ENTRY_EVT_MLE_RSC_UNPROT
struct	ENTRY_EVT_MLE_RSC_UNPROT_ERROR
struct	ENTRY_EVT_MLE_DOMAIN_TYPE_DEGRADED
union	LOG_ENTRY_DATA
struct	STM_LOG_ENTRY
struct	STM_PROTECTION_EXCEPTION_STACK_FRAME_IA32
struct	STM_PROTECTION_EXCEPTION_STACK_FRAME_X64
union	STM_PROTECTION_EXCEPTION_STACK_FRAME
struct	STM_PROTECTION_EXCEPTION_HANDLER
struct	STM_SMM_ENTRY_STATE
struct	STM_SMM_RESUME_STATE
struct	STM_SMM_STATE
struct	TXT_PROCESSOR_SMM_DESCRIPTOR

Macros
#define	STM_SPEC_VERSION_MAJOR   1
#define	STM_SPEC_VERSION_MINOR   0
#define	STM_API_MAP_ADDRESS_RANGE   0x00000001
#define	STM_API_UNMAP_ADDRESS_RANGE   0x00000002
#define	STM_API_ADDRESS_LOOKUP   0x00000003
#define	STM_API_RETURN_FROM_PROTECTION_EXCEPTION   0x00000004
#define	STM_API_START   (BIT16 | 1)
#define	STM_API_STOP   (BIT16 | 2)
#define	STM_API_PROTECT_RESOURCE   (BIT16 | 3)
#define	STM_API_UNPROTECT_RESOURCE   (BIT16 | 4)
#define	STM_API_GET_BIOS_RESOURCES   (BIT16 | 5)
#define	STM_API_MANAGE_VMCS_DATABASE   (BIT16 | 6)
#define	STM_API_INITIALIZE_PROTECTION   (BIT16 | 7)
#define	STM_API_MANAGE_EVENT_LOG   (BIT16 | 8)
#define	STM_LOG_ENTRY_SIZE   256
#define	TXT_SMM_PSD_OFFSET   0xfb00
#define	TXT_PROCESSOR_SMM_DESCRIPTOR_SIGNATURE   SIGNATURE_64('T', 'X', 'T', 'P', 'S', 'S', 'I', 'G')
#define	TXT_PROCESSOR_SMM_DESCRIPTOR_VERSION_MAJOR   1
#define	TXT_PROCESSOR_SMM_DESCRIPTOR_VERSION_MINOR   0
#define	STM_MAP_ADDRESS_RANGE_PAT_CACHE_TYPE_ST_UC   0x00
#define	STM_MAP_ADDRESS_RANGE_PAT_CACHE_TYPE_WC   0x01
#define	STM_MAP_ADDRESS_RANGE_PAT_CACHE_TYPE_WT   0x04
#define	STM_MAP_ADDRESS_RANGE_PAT_CACHE_TYPE_WP   0x05
#define	STM_MAP_ADDRESS_RANGE_PAT_CACHE_TYPE_WB   0x06
#define	STM_MAP_ADDRESS_RANGE_PAT_CACHE_TYPE_UC   0x07
#define	STM_MAP_ADDRESS_RANGE_PAT_CACHE_TYPE_FOLLOW_MTRR   0xFFFFFFFF
#define	STM_ADDRESS_LOOKUP_DESCRIPTOR_DO_NOT_MAP   0
#define	STM_ADDRESS_LOOKUP_DESCRIPTOR_ONE_TO_ONE   1
#define	STM_ADDRESS_LOOKUP_DESCRIPTOR_VIRTUAL_ADDRESS_SPECIFIED   3
#define	STM_CONFIG_SMI_UNBLOCKING_BY_VMX_OFF   BIT0
#define	DOMAIN_UNPROTECTED   0
#define	DOMAIN_DISALLOWED_IO_OUT   BIT0
#define	DOMAIN_DISALLOWED_IO_IN   BIT1
#define	DOMAIN_INTEGRITY   BIT2
#define	DOMAIN_CONFIDENTIALITY   BIT3
#define	DOMAIN_INTEGRITY_PROT_OUT_IN   (DOMAIN_INTEGRITY)
#define	DOMAIN_FULLY_PROT_OUT_IN   (DOMAIN_CONFIDENTIALITY | DOMAIN_INTEGRITY)
#define	DOMAIN_FULLY_PROT   (DOMAIN_FULLY_PROT_OUT_IN | DOMAIN_DISALLOWED_IO_IN | DOMAIN_DISALLOWED_IO_OUT)
#define	XSTATE_READWRITE   0x00
#define	XSTATE_READONLY   0x01
#define	XSTATE_SCRUB   0x03
#define	STM_VMCS_DATABASE_REQUEST_ADD   1
#define	STM_VMCS_DATABASE_REQUEST_REMOVE   0
#define	STM_RSC_BGI   BIT1
#define	STM_RSC_BGM   BIT2
#define	STM_RSC_MSR   BIT3
#define	STM_EVENT_LOG_MANAGEMENT_REQUEST_NEW_LOG   1
#define	STM_EVENT_LOG_MANAGEMENT_REQUEST_CONFIGURE_LOG   2
#define	STM_EVENT_LOG_MANAGEMENT_REQUEST_START_LOG   3
#define	STM_EVENT_LOG_MANAGEMENT_REQUEST_STOP_LOG   4
#define	STM_EVENT_LOG_MANAGEMENT_REQUEST_CLEAR_LOG   5
#define	STM_EVENT_LOG_MANAGEMENT_REQUEST_DELETE_LOG   6

Enumerations
enum	EVENT_TYPE {   EvtLogStarted, EvtLogStopped, EvtLogInvalidParameterDetected, EvtHandledProtectionException,   EvtBiosAccessToUnclaimedResource, EvtMleResourceProtectionGranted, EvtMleResourceProtectionDenied, EvtMleResourceUnprotect,   EvtMleResourceUnprotectError, EvtMleDomainTypeDegraded, EvtMleMax, EvtInvalid = 0xFFFFFFFF }
enum	TXT_SMM_PROTECTION_EXCEPTION_TYPE {   TxtSmmPageViolation = 1, TxtSmmMsrViolation, TxtSmmRegisterViolation, TxtSmmIoViolation,   TxtSmmPciViolation }

Detailed Description

STM API definition

Copyright (c) 2015 - 2019, Intel Corporation. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent

Specification Reference:

SMI Transfer Monitor (STM) User Guide Revision 1.00

Macro Definition Documentation

#define DOMAIN_CONFIDENTIALITY   BIT3

Values for the DomainType field of STM_VMCS_DATABASE_REQUEST

#define DOMAIN_DISALLOWED_IO_IN   BIT1

Values for the DomainType field of STM_VMCS_DATABASE_REQUEST

#define DOMAIN_DISALLOWED_IO_OUT   BIT0

Values for the DomainType field of STM_VMCS_DATABASE_REQUEST

#define DOMAIN_FULLY_PROT   (DOMAIN_FULLY_PROT_OUT_IN | DOMAIN_DISALLOWED_IO_IN | DOMAIN_DISALLOWED_IO_OUT)

Values for the DomainType field of STM_VMCS_DATABASE_REQUEST

#define DOMAIN_FULLY_PROT_OUT_IN   (DOMAIN_CONFIDENTIALITY | DOMAIN_INTEGRITY)

Values for the DomainType field of STM_VMCS_DATABASE_REQUEST

#define DOMAIN_INTEGRITY   BIT2

Values for the DomainType field of STM_VMCS_DATABASE_REQUEST

#define DOMAIN_INTEGRITY_PROT_OUT_IN   (DOMAIN_INTEGRITY)

Values for the DomainType field of STM_VMCS_DATABASE_REQUEST

#define DOMAIN_UNPROTECTED   0

Values for the DomainType field of STM_VMCS_DATABASE_REQUEST

#define STM_ADDRESS_LOOKUP_DESCRIPTOR_DO_NOT_MAP   0

Define values for the MapToSmmGuest field of STM_ADDRESS_LOOKUP_DESCRIPTOR

#define STM_ADDRESS_LOOKUP_DESCRIPTOR_ONE_TO_ONE   1

Define values for the MapToSmmGuest field of STM_ADDRESS_LOOKUP_DESCRIPTOR

#define STM_ADDRESS_LOOKUP_DESCRIPTOR_VIRTUAL_ADDRESS_SPECIFIED   3

Define values for the MapToSmmGuest field of STM_ADDRESS_LOOKUP_DESCRIPTOR

#define STM_API_ADDRESS_LOOKUP   0x00000003

Since the normal OS environment runs with a different set of page tables than the SMM guest, virtual mappings will certainly be different. In order to do a guest virtual to host physical translation of an address from the normal OS code (EIP for example), it is necessary to walk the page tables governing the OS page mappings. Since the SMM guest has no direct access to the page tables, it must ask the STM to do this page table walk. This is supported via the StmAddressLookup VMCALL. All OS page table formats need to be supported, (e.g. PAE, PSE, Intel64, EPT, etc.)

StmAddressLookup takes a CR3 value and a virtual address from the interrupted code as input and returns the corresponding physical address. It also optionally maps the physical address into the SMM guest's virtual address space. This new mapping persists ONLY for the duration of the SMI and if needed in subsequent SMIs it must be remapped. PAT cache types follow the interrupted environment's page table.

If EPT is enabled, OS CR3 only provides guest physical address information, but the SMM guest might also need to know the host physical address. Since SMM does not have direct access rights to EPT (it is protected by the STM), SMM can input InterruptedEptp to let STM help to walk through it, and output the host physical address.

Parameters

EAX	STM_API_ADDRESS_LOOKUP (0x00000003)
EBX	Low 32 bits of virtual address of caller allocated STM_ADDRESS_LOOKUP_DESCRIPTOR structure.
ECX	High 32 bits of virtual address of caller allocated STM_ADDRESS_LOOKUP_DESCRIPTOR structure. If Intel64Mode is clear (0), ECX must be zero.

Return values

CF	0 No error, EAX set to STM_SUCCESS. PhysicalAddress contains the host physical address determined by walking the interrupted SMM guest's page tables. SmmGuestVirtualAddress contains the SMM guest's virtual mapping of the requested address.
CF	1 An error occurred, EAX holds relevant error value.
EAX	ERROR_STM_SECURITY_VIOLATION The requested page was a protected page.
EAX	ERROR_STM_PAGE_NOT_FOUND The requested virtual address did not exist in the page given page table.
EAX	ERROR_STM_BAD_CR3 The CR3 input was invalid. CR3 values must be from one of the interrupted guest, or from the interrupted guest of another processor.
EAX	ERROR_STM_PHYSICAL_OVER_4G The resulting physical address is greater than 4G and no virtual address was supplied. The STM could not determine what address within the SMM guest's virtual address space to do the mapping. STM_ADDRESS_LOOKUP_DESCRIPTOR field PhysicalAddress contains the physical address determined by walking the interrupted environment's page tables.
EAX	ERROR_STM_VIRTUAL_SPACE_TOO_SMALL A specific virtual mapping was requested, but SmmGuestVirtualAddress + Length exceeds 4G and the SMI handler is running in 32 bit mode.
EAX	ERROR_STM_UNSPECIFIED An unspecified error occurred.

Note

All other registers unmodified.

#define STM_API_GET_BIOS_RESOURCES   (BIT16 | 5)

The GetBiosResourcesVMCALL() is invoked by the MLE root to request the list of BIOS required resources from the STM.

Parameters

EAX	STM_API_GET_BIOS_RESOURCES (0x00010005)
EBX	Low 32 bits of physical address of caller allocated destination buffer. Bits 11:0 are ignored and assumed to be zero, making the buffer 4K aligned.
ECX	High 32 bits of physical address of caller allocated destination buffer.
EDX	Indicates which page of the BIOS resource list to copy into the destination buffer. The first page is indicated by 0, the second page by 1, etc.

Return values

CF	0 No error, EAX set to STM_SUCCESS. The destination buffer contains the BIOS required resources. If the page retrieved is the last page, EDX will be cleared to 0. If there are more pages to retrieve, EDX is incremented to the next page index. Calling software should iterate on GetBiosResourcesVMCALL() until EDX is returned cleared to 0.
CF	1 An error occurred, EAX holds relevant error value.
EAX	ERROR_STM_PAGE_NOT_FOUND The page index supplied in EDX input was out of range.
EAX	ERROR_STM_UNSPECIFIED An unspecified error occurred.
EDX	Page index of next page to read. A return of EDX=0 signifies that the entire list has been read.

Note

EDX is both an input and an output register.

All other registers unmodified.

#define STM_API_INITIALIZE_PROTECTION   (BIT16 | 7)

InitializeProtectionVMCALL() prepares the STM for setup of the initial protection profile which is subsequently communicated via one or more invocations of ProtectResourceVMCALL(), prior to invoking StartStmVMCALL(). It is only necessary to invoke InitializeProtectionVMCALL() on one processor thread. InitializeProtectionVMCALL() does not alter whether SMIs are masked or unmasked. The STM should return back to the MLE with "Blocking by SMI" set to 1 in the GUEST_INTERRUPTIBILITY field for the VMCS the STM created for the MLE guest.

Parameters

EAX	STM_API_INITIALIZE_PROTECTION (0x00010007)

Return values

CF	0 No error, EAX set to STM_SUCCESS, EBX bits set to indicate STM capabilities as defined below. The STM has set up an empty protection profile, except for the resources that it sets up to protect itself. The STM must not allow the SMI handler to map any pages from the MSEG Base to the top of TSEG. The STM must also not allow SMI handler access to those MSRs which the STM requires for its own protection.
CF	1 An error occurred, EAX holds relevant error value.
EAX	ERROR_STM_ALREADY_STARTED The STM is already configured and active. The STM remains active and guarding the previously enabled resource list.
EAX	ERROR_STM_UNPROTECTABLE The STM determines that based on the platform configuration, the STM is unable to protect itself. For example, the BIOS required resource list contains memory pages in MSEG.
EAX	ERROR_STM_UNSPECIFIED An unspecified error occurred.

Note

All other registers unmodified.

#define STM_API_MANAGE_EVENT_LOG   (BIT16 | 8)

The ManageEventLogVMCALL() is invoked by the MLE root to control the logging feature. It consists of several sub-functions to facilitate establishment of the log itself, configuring what events will be logged, and functions to start, stop, and clear the log.

Parameters

EAX	STM_API_MANAGE_EVENT_LOG (0x00010008)
EBX	Low 32 bits of physical address of caller allocated STM_EVENT_LOG_MANAGEMENT_REQUEST. Bits 11:0 are ignored and assumed to be zero, making the buffer 4K aligned.
ECX	High 32 bits of physical address of caller allocated STM_EVENT_LOG_MANAGEMENT_REQUEST.

Return values

CF=0	No error, EAX set to STM_SUCCESS.
CF=1	An error occurred, EAX holds relevant error value. See subfunction descriptions below for details.

Note

All other registers unmodified.

#define STM_API_MANAGE_VMCS_DATABASE   (BIT16 | 6)

The ManageVmcsDatabaseVMCALL() is invoked by the MLE root to add or remove an MLE guest (including the MLE root) from the list of protected domains.

Parameters

EAX	STM_API_MANAGE_VMCS_DATABASE (0x00010006)
EBX	Low 32 bits of physical address of caller allocated STM_VMCS_DATABASE_REQUEST. Bits 11:0 are ignored and assumed to be zero, making the buffer 4K aligned.
ECX	High 32 bits of physical address of caller allocated STM_VMCS_DATABASE_REQUEST.

Note

All fields of STM_VMCS_DATABASE_REQUEST are inputs only. They are not modified by ManageVmcsDatabaseVMCALL().

Return values

CF	0 No error, EAX set to STM_SUCCESS.
CF	1 An error occurred, EAX holds relevant error value.
EAX	#ERROR_STM_INVALID_VMCS Indicates a request to remove a VMCS from the database was made, but the referenced VMCS was not found in the database.
EAX	#ERROR_STM_VMCS_PRESENT Indicates a request to add a VMCS to the database was made, but the referenced VMCS was already present in the database.
EAX	ERROR_INVALID_PARAMETER Indicates non-zero reserved field.
EAX	ERROR_STM_UNSPECIFIED An unspecified error occurred

Note

All other registers unmodified.

#define STM_API_MAP_ADDRESS_RANGE   0x00000001

VMCALL API Numbers API number convention: BIOS facing VMCALL interfaces have bit 16 clear StmMapAddressRange enables a SMM guest to create a non-1:1 virtual to physical mapping of an address range into the SMM guest's virtual memory space.

Parameters

EAX	STM_API_MAP_ADDRESS_RANGE (0x00000001)
EBX	Low 32 bits of physical address of caller allocated STM_MAP_ADDRESS_RANGE_DESCRIPTOR structure.
ECX	High 32 bits of physical address of caller allocated STM_MAP_ADDRESS_RANGE_DESCRIPTOR structure. If Intel64Mode is clear (0), ECX must be 0.

Note

All fields of STM_MAP_ADDRESS_RANGE_DESCRIPTOR are inputs only. They are not modified by StmMapAddressRange.

Return values

CF	0 No error, EAX set to STM_SUCCESS. The memory range was mapped as requested.
CF	1 An error occurred, EAX holds relevant error value.
EAX	ERROR_STM_SECURITY_VIOLATION The requested mapping contains a protected resource.
EAX	ERROR_STM_CACHE_TYPE_NOT_SUPPORTED The requested cache type could not be satisfied.
EAX	ERROR_STM_PAGE_NOT_FOUND Page count must not be zero.
EAX	ERROR_STM_FUNCTION_NOT_SUPPORTED STM supports EPT and has not implemented StmMapAddressRange().
EAX	ERROR_STM_UNSPECIFIED An unspecified error occurred.

Note

All other registers unmodified.

#define STM_API_PROTECT_RESOURCE   (BIT16 | 3)

The ProtectResourceVMCALL() is invoked by the MLE root to request protection of specific resources. The request is defined by a STM_RESOURCE_LIST, which may contain more than one resource descriptor. Each resource descriptor is processed separately by the STM. Whether or not protection for any specific resource is granted is returned by the STM via the ReturnStatus bit in the associated STM_RSC_DESC_HEADER.

Parameters

EAX	STM_API_PROTECT_RESOURCE (0x00010003)
EBX	Low 32 bits of physical address of caller allocated STM_RESOURCE_LIST. Bits 11:0 are ignored and assumed to be zero, making the buffer 4K aligned.
ECX	High 32 bits of physical address of caller allocated STM_RESOURCE_LIST.

Note

All fields of STM_RESOURCE_LIST are inputs only, except for the ReturnStatus bit. On input, the ReturnStatus bit must be clear. On return, the ReturnStatus bit is set for each resource request granted, and clear for each resource request denied. There are no other fields modified by ProtectResourceVMCALL(). The STM_RESOURCE_LIST must be contained entirely within a single 4K page.

Return values

CF	0 No error, EAX set to STM_SUCCESS. The STM has successfully merged the entire protection request into the active protection profile. There is therefore no need to check the ReturnStatus bits in the STM_RESOURCE_LIST.
CF	1 An error occurred, EAX holds relevant error value.
EAX	ERROR_STM_UNPROTECTABLE_RESOURCE At least one of the requested resource protections intersects a BIOS required resource. Therefore, the caller must walk through the STM_RESOURCE_LIST to determine which of the requested resources was not granted protection. The entire list must be traversed since there may be multiple failures.
EAX	ERROR_STM_MALFORMED_RESOURCE_LIST The resource list could not be parsed correctly, or did not terminate before crossing a 4K page boundary. The caller must walk through the STM_RESOURCE_LIST to determine which of the requested resources was not granted protection. The entire list must be traversed since there may be multiple failures.
EAX	ERROR_STM_OUT_OF_RESOURCES The STM has encountered an internal error and cannot complete the request.
EAX	ERROR_STM_UNSPECIFIED An unspecified error occurred.

Note

All other registers unmodified.

#define STM_API_RETURN_FROM_PROTECTION_EXCEPTION   0x00000004

When returning from a protection exception (see section 6.2), the SMM guest can instruct the STM to take one of two paths. It can either request a value be logged to the TXT.ERRORCODE register and subsequently reset the machine (indicating it couldn't resolve the problem), or it can request that the STM resume the SMM guest again with the specified register state.

Unlike other VMCALL interfaces, StmReturnFromProtectionException behaves more like a jump or an IRET instruction than a "call". It does not return directly to the caller, but indirectly to a different location specified on the caller's stack (see section 6.2) or not at all.

If the SMM guest STM protection exception handler itself causes a protection exception (e.g. a single nested exception), or more than 100 un-nested exceptions occur within the scope of a single SMI event, the STM must write STM_CRASH_PROTECTION_EXCEPTION_FAILURE to the TXT.ERRORCODE register and assert TXT.CMD.SYS_RESET. The reason for these restrictions is to simplify the code requirements while still enabling a reasonable debugging capability.

Parameters

EAX	STM_API_RETURN_FROM_PROTECTION_EXCEPTION (0x00000004)
EBX	If 0, resume SMM guest using register state found on exception stack. If in range 0x01..0x0F, EBX contains a BIOS error code which the STM must record in the TXT.ERRORCODE register and subsequently reset the system via TXT.CMD.SYS_RESET. The value of the TXT.ERRORCODE register is calculated as follows:

TXT.ERRORCODE = (EBX & 0x0F) | STM_CRASH_BIOS_PANIC

Values 0x10..0xFFFFFFFF are reserved, do not use.

#define STM_API_START   (BIT16 | 1)

VMCALL API Numbers API number convention: MLE facing VMCALL interfaces have bit 16 set.

The STM configuration lifecycle is as follows:

1. SENTER->SINIT->MLE: MLE begins execution with SMI disabled (masked).
2. MLE invokes STM_API_INITIALIZE_PROTECTION VMCALL to prepare STM for setup of initial protection profile. This is done on a single CPU and has global effect.
3. MLE invokes STM_API_PROTECT_RESOURCE VMCALL to define the initial protection profile. The protection profile is global across all CPUs.
4. MLE invokes STM_API_START VMCALL to enable the STM to begin receiving SMI events. This must be done on every logical CPU.
5. MLE may invoke STM_API_PROTECT_RESOURCE VMCALL or STM_API_UNPROTECT_RESOURCE VMCALL during runtime as many times as necessary.
6. MLE invokes STM_API_STOP VMCALL to disable the STM. SMI is again masked following STM_API_STOP VMCALL. StartStmVmcall() is used to configure an STM that is present in MSEG. SMIs should remain disabled from the invocation of GETSEC[SENTER] until they are re-enabled by StartStmVMCALL(). When StartStmVMCALL() returns, SMI is enabled and the STM has been started and is active. Prior to invoking StartStmVMCALL(), the MLE root should first invoke InitializeProtectionVMCALL() followed by as many iterations of ProtectResourceVMCALL() as necessary to establish the initial protection profile. StartStmVmcall() must be invoked on all processor threads.

Parameters

EAX	STM_API_START (0x00010001)
EDX	STM configuration options. These provide the MLE with the ability to pass configuration parameters to the STM.

Return values

CF	0 No error, EAX set to STM_SUCCESS. The STM has been configured and is now active and the guarding all requested resources.
CF	1 An error occurred, EAX holds relevant error value.
EAX	ERROR_STM_ALREADY_STARTED The STM is already configured and active. STM remains active and guarding previously enabled resource list.
EAX	ERROR_STM_WITHOUT_SMX_UNSUPPORTED The StartStmVMCALL() was invoked from VMX root mode, but outside of SMX. This error code indicates the STM or platform does not support the STM outside of SMX. The SMI handler remains active and operates in legacy mode. See Appendix C
EAX	ERROR_STM_UNSUPPORTED_MSR_BIT The CPU doesn't support the MSR bit. The STM is not active.
EAX	ERROR_STM_UNSPECIFIED An unspecified error occurred.

Note

All other registers unmodified.

#define STM_API_STOP   (BIT16 | 2)

The StopStmVMCALL() is invoked by the MLE to teardown an active STM. This is normally done as part of a full teardown of the SMX environment when the system is being shut down. At the time the call is invoked, SMI is enabled and the STM is active. When the call returns, the STM has been stopped and all STM context is discarded and SMI is disabled.

Parameters

EAX	STM_API_STOP (0x00010002)

Return values

CF	0 No error, EAX set to STM_SUCCESS. The STM has been stopped and is no longer processing SMI events. SMI is blocked.
CF	1 An error occurred, EAX holds relevant error value.
EAX	ERROR_STM_STOPPED The STM was not active.
EAX	ERROR_STM_UNSPECIFIED An unspecified error occurred.

Note

All other registers unmodified.

#define STM_API_UNMAP_ADDRESS_RANGE   0x00000002

StmUnmapAddressRange enables a SMM guest to remove mappings from its page table.

If TXT_PROCESSOR_SMM_DESCRIPTOR.EptEnabled bit is set by the STM, BIOS can control its own page tables. In this case, the STM implementation may optionally return ERROR_STM_FUNCTION_NOT_SUPPORTED.

Parameters

EAX	STM_API_UNMAP_ADDRESS_RANGE (0x00000002)
EBX	Low 32 bits of virtual address of caller allocated STM_UNMAP_ADDRESS_RANGE_DESCRIPTOR structure.
ECX	High 32 bits of virtual address of caller allocated STM_UNMAP_ADDRESS_RANGE_DESCRIPTOR structure. If Intel64Mode is clear (0), ECX must be zero.

Return values

CF	0 No error, EAX set to STM_SUCCESS. The memory range was unmapped as requested.
CF	1 An error occurred, EAX holds relevant error value.
EAX	ERROR_STM_FUNCTION_NOT_SUPPORTED STM supports EPT and has not implemented StmUnmapAddressRange().
EAX	ERROR_STM_UNSPECIFIED An unspecified error occurred.

Note

All other registers unmodified.

#define STM_API_UNPROTECT_RESOURCE   (BIT16 | 4)

The UnProtectResourceVMCALL() is invoked by the MLE root to request that the STM allow the SMI handler access to the specified resources.

Parameters

EAX	STM_API_UNPROTECT_RESOURCE (0x00010004)
EBX	Low 32 bits of physical address of caller allocated STM_RESOURCE_LIST. Bits 11:0 are ignored and assumed to be zero, making the buffer 4K aligned.
ECX	High 32 bits of physical address of caller allocated STM_RESOURCE_LIST.

Note

All fields of STM_RESOURCE_LIST are inputs only, except for the ReturnStatus bit. On input, the ReturnStatus bit must be clear. On return, the ReturnStatus bit is set for each resource processed. For a properly formed STM_RESOURCE_LIST, this should be all resources listed. There are no other fields modified by UnProtectResourceVMCALL(). The STM_RESOURCE_LIST must be contained entirely within a single 4K page.

Return values

CF	0 No error, EAX set to STM_SUCCESS. The requested resources are not being guarded by the STM.
CF	1 An error occurred, EAX holds relevant error value.
EAX	ERROR_STM_MALFORMED_RESOURCE_LIST The resource list could not be parsed correctly, or did not terminate before crossing a 4K page boundary. The caller must walk through the STM_RESOURCE_LIST to determine which of the requested resources were not able to be unprotected. The entire list must be traversed since there may be multiple failures.
EAX	ERROR_STM_UNSPECIFIED An unspecified error occurred.

Note

All other registers unmodified.

#define STM_CONFIG_SMI_UNBLOCKING_BY_VMX_OFF   BIT0

Bit values for EDX input parameter to STM_API_START VMCALL

#define STM_EVENT_LOG_MANAGEMENT_REQUEST_CLEAR_LOG   5

Defines values for the SubFunctionIndex field of STM_EVENT_LOG_MANAGEMENT_REQUEST

#define STM_EVENT_LOG_MANAGEMENT_REQUEST_CONFIGURE_LOG   2

Defines values for the SubFunctionIndex field of STM_EVENT_LOG_MANAGEMENT_REQUEST

#define STM_EVENT_LOG_MANAGEMENT_REQUEST_DELETE_LOG   6

Defines values for the SubFunctionIndex field of STM_EVENT_LOG_MANAGEMENT_REQUEST

#define STM_EVENT_LOG_MANAGEMENT_REQUEST_NEW_LOG   1

Defines values for the SubFunctionIndex field of STM_EVENT_LOG_MANAGEMENT_REQUEST

#define STM_EVENT_LOG_MANAGEMENT_REQUEST_START_LOG   3

Defines values for the SubFunctionIndex field of STM_EVENT_LOG_MANAGEMENT_REQUEST

#define STM_EVENT_LOG_MANAGEMENT_REQUEST_STOP_LOG   4

Defines values for the SubFunctionIndex field of STM_EVENT_LOG_MANAGEMENT_REQUEST

#define STM_LOG_ENTRY_SIZE   256

Maximum STM Log Entry Size

#define STM_MAP_ADDRESS_RANGE_PAT_CACHE_TYPE_FOLLOW_MTRR   0xFFFFFFFF

Define values for PatCacheType field of STM_MAP_ADDRESS_RANGE_DESCRIPTOR

#define STM_MAP_ADDRESS_RANGE_PAT_CACHE_TYPE_ST_UC   0x00

Define values for PatCacheType field of STM_MAP_ADDRESS_RANGE_DESCRIPTOR

#define STM_MAP_ADDRESS_RANGE_PAT_CACHE_TYPE_UC   0x07

Define values for PatCacheType field of STM_MAP_ADDRESS_RANGE_DESCRIPTOR

#define STM_MAP_ADDRESS_RANGE_PAT_CACHE_TYPE_WB   0x06

Define values for PatCacheType field of STM_MAP_ADDRESS_RANGE_DESCRIPTOR

#define STM_MAP_ADDRESS_RANGE_PAT_CACHE_TYPE_WC   0x01

Define values for PatCacheType field of STM_MAP_ADDRESS_RANGE_DESCRIPTOR

#define STM_MAP_ADDRESS_RANGE_PAT_CACHE_TYPE_WP   0x05

Define values for PatCacheType field of STM_MAP_ADDRESS_RANGE_DESCRIPTOR

#define STM_MAP_ADDRESS_RANGE_PAT_CACHE_TYPE_WT   0x04

Define values for PatCacheType field of STM_MAP_ADDRESS_RANGE_DESCRIPTOR

#define STM_RSC_BGI   BIT1

Byte granular support bits returned in EBX from STM_API_INITIALIZE_PROTECTION

#define STM_RSC_BGM   BIT2

Byte granular support bits returned in EBX from STM_API_INITIALIZE_PROTECTION

#define STM_RSC_MSR   BIT3

Byte granular support bits returned in EBX from STM_API_INITIALIZE_PROTECTION

#define STM_SPEC_VERSION_MAJOR   1

#define STM_SPEC_VERSION_MINOR   0

#define STM_VMCS_DATABASE_REQUEST_ADD   1

Values for the AddOrRemove field of STM_VMCS_DATABASE_REQUEST

#define STM_VMCS_DATABASE_REQUEST_REMOVE   0

Values for the AddOrRemove field of STM_VMCS_DATABASE_REQUEST

#define TXT_PROCESSOR_SMM_DESCRIPTOR_SIGNATURE   SIGNATURE_64('T', 'X', 'T', 'P', 'S', 'S', 'I', 'G')

#define TXT_PROCESSOR_SMM_DESCRIPTOR_VERSION_MAJOR   1

#define TXT_PROCESSOR_SMM_DESCRIPTOR_VERSION_MINOR   0

#define TXT_SMM_PSD_OFFSET   0xfb00

#define XSTATE_READONLY   0x01

Values for the XStatePolicy field of STM_VMCS_DATABASE_REQUEST

#define XSTATE_READWRITE   0x00

Values for the XStatePolicy field of STM_VMCS_DATABASE_REQUEST

#define XSTATE_SCRUB   0x03

Values for the XStatePolicy field of STM_VMCS_DATABASE_REQUEST

Enumeration Type Documentation

enum EVENT_TYPE

Enum values for the Type field of LOG_ENTRY_HEADER

Enumerator
EvtLogStarted
EvtLogStopped
EvtLogInvalidParameterDetected
EvtHandledProtectionException
EvtBiosAccessToUnclaimedResource	unhandled protection exceptions result in reset & cannot be logged
EvtMleResourceProtectionGranted
EvtMleResourceProtectionDenied
EvtMleResourceUnprotect
EvtMleResourceUnprotectError
EvtMleDomainTypeDegraded
EvtMleMax	add more here
EvtInvalid	Not used

enum TXT_SMM_PROTECTION_EXCEPTION_TYPE

Enum values for the ErrorCode field in STM_PROTECTION_EXCEPTION_STACK_FRAME_IA32 and STM_PROTECTION_EXCEPTION_STACK_FRAME_X64

Enumerator
TxtSmmPageViolation
TxtSmmMsrViolation
TxtSmmRegisterViolation
TxtSmmIoViolation
TxtSmmPciViolation