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!verifier 3

Bill_WandelBill_Wandel Member - All Emails Posts: 237
via Email in WINDBG
I am looking into a memory leak using windbg and verifier. Stopping the
driver gives me the C4/62 crash. When I enter "!verifier 3" the debugger
just stays busy after printing out the address/length/tag header.

My windbg version is 1803.

Bill Wandel


  • Scott_Noone_(OSR)Scott_Noone_(OSR) Administrator Posts: 3,375

    What's the target O/S version? If you CTRL+ALT+D can you see the debugger chatting with the target or is it just hanging there?


  • Bill_WandelBill_Wandel Member - All Emails Posts: 237
    via Email
    It is WIN10 RS5. I can stop it with the debug/stop.

    Bill Wandel
  • Scott_Noone_(OSR)Scott_Noone_(OSR) Administrator Posts: 3,375

    Just tried it with WinDbg 17763 and OS 17758 and finished just fine:

    Driver Verification List
    nt!_VF_TARGET_DRIVER 0xffffa486435decc0: Nothing.sys (Loaded)
        Pool Allocation Statistics: ( NonPagedPool / PagedPool )
          Current Pool Allocations: ( 0x00000001 / 0x00000000 )
          Current Pool Bytes:       ( 0x00000064 / 0x00000000 )
          Peak Pool Allocations:    ( 0x00000001 / 0x00000000 )
          Peak Pool Bytes:          ( 0x00000064 / 0x00000000 )
          Contiguous Memory Bytes:       0x00000000
          Peak Contiguous Memory Bytes:  0x00000000
        Pool Allocations:
          Address             Length      Tag   Caller Address    
          ------------------  ----------  ----  ------------------
          0xffffa48643d02f90  0x00000064  xxxx  0xfffff807676d14f3  Nothing!DriverEntry+0x1d3
        Contiguous allocations are not displayed with public symbols.

    Does CTRL+ALT+D show traffic? Do you think you have a LOT of leaked allocations?


  • Bill_WandelBill_Wandel Member - All Emails Posts: 237
    via Email
    Thanks. I can run my tests on WIN8.1. It should work there.

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