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HLK Flush Test for Virtual Storport miniport

blangeblange Member Posts: 24

With the release of Windows 11, the HLK suddenly requests the Flush test for my Virtual Storport miniport (based on the instructive OSR blog). After connecting the required PDU the test starts with trying to write data to a cache and the flush it according to the test log. This operation fails, resulting in a test clean with formating the virtual disk, which then render the virtual disk useless.
I am logging the SRBs send to my driver (especially the ones which I do not support), however, I do not see the corresponding write request or synchronize cache request. I am also quite positive that I set the necessary bits in the Caching VDP that my device does not support caching.

I wonder if anybody here faces a similar problem with HLK or could shed some light on this Windows Flush test and its requirements. Other required HLK tests pass.


  • Scott_Noone_(OSR)Scott_Noone_(OSR) Administrator Posts: 3,465

    Have you managed to extract the right executables/command line so that you can run the test outside of the HLK? Would be much easier to track down because we can start setting breakpoints in the debugger.


  • blangeblange Member Posts: 24

    Hi Scott. Thank you for your reply. I will try to extract the corresponding command.

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