MdlAfterReqCompletedWriteA rule (kmdf)

The MdlAfterReqCompletedWriteA rule specifies that within the EvtIoWrite callback function, the memory descriptor list (MDL) object retrieved cannot be accessed after the I/O request is completed.

Within the driver's EvtIoWrite callback function for a device's I/O queue, the request buffer that was retrieved by calling the WdfRequestRetrieveInputWdmMdl method cannot be accessed after calling WdfRequestComplete, WdfRequestCompleteWithInformation, or WdfRequestCompleteWithPriorityBoost on the I/O request.

This rule considers the following MDL access functions:

WDF_MEMORY_DESCRIPTOR_INIT_MDL MmGetMdlByteCount MmGetSystemAddressForMdlSafe MmGetMdlVirtualAddress IoBuildPartialMdl (first and second parameter) KeFlushIoBuffers MmGetMdlPfnArray MmGetMdlByteOffset MmPrepareMdlForReuse WdfDmaTransactionInitialize

Driver model: KMDF

How to test

At compile time
Run Static Driver Verifier and specify the MdlAfterReqCompletedWriteA rule. Use the following steps to run an analysis of your code: Prepare your code (use role type declarations). Run Static Driver Verifier. View and analyze the results. For more information, see Using Static Driver Verifier to Find Defects in Drivers.

Applies to

WDF_MEMORY_DESCRIPTOR_INIT_MDL WdfDmaTransactionInitialize WdfRequestComplete WdfRequestCompleteWithInformation WdfRequestCompleteWithPriorityBoost WdfRequestRetrieveInputWdmMdl IoBuildPartialMdl KeFlushIoBuffers MmGetMdlByteCount MmGetMdlByteOffset MmGetMdlPfnArray MmGetMdlVirtualAddress MmGetSystemAddressForMdlSafe MmPrepareMdlForReuse