MINIPORT_CHECK_FOR_HANG callback function


The MiniportCheckForHangEx and MiniportResetEx callback functions are discouraged for all NDIS 6.83 and later drivers. For more information, see Check-for-Hang and Reset operations in NDIS 6.83 and later.

NDIS calls a miniport driver's MiniportCheckForHangEx function to check the operational state of the miniport adapter that represents a network interface card (NIC).

Note  A miniport driver may declare this function by using the MINIPORT_CHECK_FOR_HANG type.
Note  Starting with NDIS 6.30, this function must not be registered for drivers running on low power SoC platforms to avoid negative power impact caused by the periodic Check-for-Hang activity.



BOOLEAN MiniportCheckForHang(
  NDIS_HANDLE MiniportAdapterContext



A handle to a context area that the miniport driver allocated in its MiniportInitializeEx function. The miniport driver uses this context area to maintain state information for a miniport adapter.

Return Value

MiniportCheckForHangEx returns TRUE if the driver determines that a NIC is not operating and NDIS should call the driver's MiniportResetEx function. For more information, see the Remarks section.


A miniport driver specifies the MiniportCheckForHangEx entry point when it calls the NdisMRegisterMiniportDriver function.

MiniportCheckForHangEx is not required for intermediate drivers.

MiniportCheckForHangEx does nothing more than check the internal state of the NIC and return TRUE if it detects that the NIC is not operating correctly.

By default, NDIS calls MiniportCheckForHangEx approximately every two seconds. For this reason, your miniport driver's MiniportCheckForHangEx function should return as quickly as possible.

Note  Starting with NDIS 6.30, a coalescable timer with high tolerance is used for measuring intervals between calls to MiniportCheckForHangEx. Therefore this routine should not be used for any time sensitive operations.
If MiniportCheckForHangEx returns TRUE, NDIS calls the miniport driver's MiniportResetEx function.

If a miniport driver does not complete an OID request within two successive calls to MiniportCheckForHangEx, NDIS can call the driver's MiniportResetEx function. However, to avoid unnecessary resets, the driver's MiniportInitializeEx function can extend the check-for-hang time-out interval by setting an appropriate CheckForHangTimeInSeconds value when it calls the NdisMSetMiniportAttributes function.

For more information about setting the CheckForHangTimeInSeconds time-out value, see Miniport Adapter Check-for-Hang and Reset Operations.

Note  Starting with NDIS 6.30, MiniportCheckForHangEx must return TRUE if the miniport driver detects that the NIC has not completed a pending send request before a time-out period expired. The time-out period is driver-specific, but we recommend using a timeout period of 2 seconds.
MiniportCheckForHangEx can be preempted by an interrupt.

NDIS calls MiniportCheckForHangEx at IRQL = PASSIVE_LEVEL.


To define a MiniportCheckForHangEx function, you must first provide a function declaration that identifies the type of function you're defining. Windows provides a set of function types for drivers. Declaring a function using the function types helps Code Analysis for Drivers, Static Driver Verifier (SDV), and other verification tools find errors, and it's a requirement for writing drivers for the Windows operating system.

For example, to define a MiniportCheckForHangEx function that is named "MyCheckForHangEx", use the MINIPORT_CHECK_FOR_HANG type as shown in this code example:

Then, implement your function as follows:
    NDIS_HANDLE  MiniportAdapterContext
The MINIPORT_CHECK_FOR_HANG function type is defined in the Ndis.h header file. To more accurately identify errors when you run the code analysis tools, be sure to add the _Use_decl_annotations_ annotation to your function definition. The _Use_decl_annotations_ annotation ensures that the annotations that are applied to the MINIPORT_CHECK_FOR_HANG function type in the header file are used. For more information about the requirements for function declarations, see Declaring Functions by Using Function Role Types for NDIS Drivers.

For information about Use_decl_annotations, see Annotating Function Behavior.


Minimum supported client Supported in NDIS 6.0 and later.
Target Platform Windows
Header ndis.h (include Ndis.h)

See Also

Miniport Adapter Check-for-Hang and Reset Operations