UMDF driver stack RRS feed

  • Question

  • Hi,

    I’m trying to better understand the driver stack architecture, as I read an UMDF driver could be function driver or filter driver. There is a restriction of the number of function UMDF DO in the same stack? (Same as in KMDF driver stack?)

    When I have a driver stack that contains both KMDF devices and UMDF devices, how many functional drivers is possible? If the answer for my first question is yes, I understand that 2 function driver is possible, one KMDF FDO and one UMDF FDO. Is it right?



    Sunday, March 10, 2013 8:37 AM


  • No matte what technology, there is only one fdo (function device object), IE the primary owner of the stack who dictates the Io interface, power policy, etc. You can have any number of filters above and below the fdo. Filters and FDOs can always km(DF) drivers, sometimes umdf drivers

    d -- This posting is provided "AS IS" with no warranties, and confers no rights.

    Sunday, March 10, 2013 3:05 PM