Intermittent Cc "Assertion failed: Vacb->Dirty", on shutdown, on Test KVM

WARNING:  HvHiveWillShrink at sdk/lib/cmlib/hivewrt.c:280 is UNIMPLEMENTED!

*** Assertion failed: Vacb->Dirty

***   Source File: /srv/buildbot/Build_GCCLin_x86/build/ntoskrnl/cc/view.c, line 553

Break repeatedly, break Once, Ignore, terminate Process or terminate Thread (boipt)? 

kdb:>

 o

Execute '.cxr F6E066D4' to dump context

Entered debugger on embedded INT3 at 0x0008:0x8094c9be.

kdb:>

 bt

Eip:

<NTOSKRNL.EXE:14c9bf (:0 (DbgBreakPoint))>

Frames:

<NTOSKRNL.EXE:a740 (ntoskrnl/cc/view.c:553 (CcRosUnmarkDirtyVacb))>

<NTOSKRNL.EXE:a9aa (ntoskrnl/cc/view.c:174 (CcRosFlushVacb))>

<NTOSKRNL.EXE:be7b (ntoskrnl/cc/view.c:1037 (CcFlushCache))>

<NTOSKRNL.EXE:c131 (ntoskrnl/cc/view.c:1079 (CcRosDeleteFileCache))>

<NTOSKRNL.EXE:d039 (ntoskrnl/cc/view.c:1188 (CcRosDereferenceCache))>

<NTOSKRNL.EXE:ef2d2 (ntoskrnl/mm/section.c:2715 (MmpDeleteSection))>

<NTOSKRNL.EXE:fab53 (ntoskrnl/ob/oblife.c:211 (ObpDeleteObject))>

<NTOSKRNL.EXE:1004bb (ntoskrnl/ob/obref.c:345 (ObfDereferenceObject))>

<NTOSKRNL.EXE:f69cc (ntoskrnl/ob/obhandle.c:767 (ObpCloseHandleTableEntry))>

<NTOSKRNL.EXE:f6a13 (ntoskrnl/ob/obhandle.c:1927 (ObpCloseHandleCallback))>

<NTOSKRNL.EXE:33646 (ntoskrnl/ex/handle.c:1215 (ExSweepHandleTable))>

<NTOSKRNL.EXE:f86f1 (ntoskrnl/ob/obhandle.c:2182 (ObKillProcess))>

<NTOSKRNL.EXE:10b312 (ntoskrnl/ps/kill.c:837 (PspExitThread))>

<NTOSKRNL.EXE:10b7be (ntoskrnl/ps/kill.c:940 (PsExitSpecialApc))>

<NTOSKRNL.EXE:86d9a (ntoskrnl/ke/apc.c:474 (KiDeliverApc))>

<NTOSKRNL.EXE:12e2b5 (ntoskrnl/include/internal/i386/ke.h:782 (KiServiceExit))>

<NTOSKRNL.EXE:1310da (ntoskrnl/ke/i386/traphdlr.c:1826 (KiSystemServiceHandler))>

<NTOSKRNL.EXE:3da9 (:0 (KiFastCallEntry))>

<ntdll.dll:d7c5>

<kernel32.dll:16e88>

<wmisvc.dll:1349>

<svchost.exe:3858>

<advapi32.dll:1bbdf>

<kernel32.dll:1b5ca>

<00000000>

kdb:>

[SYSREG] Stage took: 1863.344942 seconds

[SYSREG] Status: Reached the checkpoint!

program finished with exit code 0

*** Assertion failed: Vacb->Dirty

***   Source File: /srv/buildbot/Build_GCCLin_x86/build/ntoskrnl/cc/view.c, line 553

Break repeatedly, break Once, Ignore, terminate Process or terminate Thread (boipt)? 

kdb:>

 o

Execute '.cxr F75562B4' to dump context

Entered debugger on embedded INT3 at 0x0008:0x8094c9ce.

kdb:>

 bt

Eip:

<NTOSKRNL.EXE:14c9cf (:0 (DbgBreakPoint))>

Frames:

<NTOSKRNL.EXE:a740 (ntoskrnl/cc/view.c:553 (CcRosUnmarkDirtyVacb))>

<NTOSKRNL.EXE:a9aa (ntoskrnl/cc/view.c:174 (CcRosFlushVacb))>

<NTOSKRNL.EXE:be7b (ntoskrnl/cc/view.c:1037 (CcFlushCache))>

<fastfat.sys:db1e>

<fastfat.sys:dbbb>

<fastfat.sys:dee6>

<fastfat.sys:102b5>

<fastfat.sys:10785>

<NTOSKRNL.EXE:715f5 (ntoskrnl/io/iomgr/irp.c:1286 (IofCallDriver))>

<NTOSKRNL.EXE:68f81 (ntoskrnl/io/iomgr/iofunc.c:142 (IopPerformSynchronousRequest))>

<NTOSKRNL.EXE:6aacf (ntoskrnl/io/iomgr/iofunc.c:1475 (NtFlushBuffersFile))>

<NTOSKRNL.EXE:13101e (ntoskrnl/include/internal/i386/ke.h:712 (KiSystemServiceHandler))>

<NTOSKRNL.EXE:3d1f (:0 (KiSystemService))>

<NTOSKRNL.EXE:1660 (:0 (ZwFlushBuffersFile))>

<NTOSKRNL.EXE:1063a5 (ntoskrnl/po/povolume.c:353 (PopFlushVolumes))>

<NTOSKRNL.EXE:107654 (ntoskrnl/po/power.c:963 (NtSetSystemPowerState))>

<NTOSKRNL.EXE:13101e (ntoskrnl/include/internal/i386/ke.h:712 (KiSystemServiceHandler))>

<NTOSKRNL.EXE:3d1f (:0 (KiSystemService))>

<NTOSKRNL.EXE:2394 (:0 (ZwSetSystemPowerState))>

<NTOSKRNL.EXE:3b861 (ntoskrnl/ex/shutdown.c:67 (NtShutdownSystem))>

<NTOSKRNL.EXE:13101e (ntoskrnl/include/internal/i386/ke.h:712 (KiSystemServiceHandler))>

<NTOSKRNL.EXE:3da9 (:0 (KiFastCallEntry))>

<ntdll.dll:d7c5>

<winlogon.exe:4b9c>

<winlogon.exe:578a>

<user32.dll:61699>

<user32.dll:5574b>

<user32.dll:55b94>

<user32.dll:562c1>

<winlogon.exe:7fc2>

<winlogon.exe:c8f8>

<winlogon.exe:ba02>

<winlogon.exe:ba4b>

<00000000>

kdb:>

[SYSREG] Stage took: 1875.329946 seconds

[SYSREG] Status: Reached the checkpoint!

program finished with exit code 0

*** Assertion failed: Vacb->Dirty

***   Source File: /srv/buildbot/Build_GCCLin_x86/build/ntoskrnl/cc/view.c, line 553

Break repeatedly, break Once, Ignore, terminate Process or terminate Thread (boipt)? 

kdb:>

 o

Execute '.cxr F755A4DC' to dump context

Entered debugger on embedded INT3 at 0x0008:0x8094ce7e.

kdb:>

 bt

Eip:

<NTOSKRNL.EXE:14ce7f (:0 (DbgBreakPoint))>

Frames:

<NTOSKRNL.EXE:a740 (ntoskrnl/cc/view.c:553 (CcRosUnmarkDirtyVacb))>

<NTOSKRNL.EXE:a9aa (ntoskrnl/cc/view.c:174 (CcRosFlushVacb))>

<NTOSKRNL.EXE:be7b (ntoskrnl/cc/view.c:1037 (CcFlushCache))>

<fastfat.sys:db7e>

<fastfat.sys:dc1b>

<fastfat.sys:df46>

<fastfat.sys:10315>

<fastfat.sys:107e5>

<NTOSKRNL.EXE:71905 (ntoskrnl/io/iomgr/irp.c:1286 (IofCallDriver))>

<NTOSKRNL.EXE:69291 (ntoskrnl/io/iomgr/iofunc.c:142 (IopPerformSynchronousRequest))>

<NTOSKRNL.EXE:6addf (ntoskrnl/io/iomgr/iofunc.c:1475 (NtFlushBuffersFile))>

<NTOSKRNL.EXE:1314ce (ntoskrnl/include/internal/i386/ke.h:712 (KiSystemServiceHandler))>

<NTOSKRNL.EXE:3d1f (:0 (KiSystemService))>

<NTOSKRNL.EXE:1660 (:0 (ZwFlushBuffersFile))>

<NTOSKRNL.EXE:1160f4 (ntoskrnl/ps/thread.c:156 (PspSystemThreadStartup))>

<NTOSKRNL.EXE:12d435 (ntoskrnl/ke/i386/thrdini.c:78 (KiThreadStartup))>

<NTOSKRNL.EXE:1160bb (ntoskrnl/ps/state.c:565 (NtQueueApcThread))>

<5d8950ec>

<00000000>

kdb:>

[SYSREG] Stage took: 1955.951264 seconds

[SYSREG] Status: Reached the checkpoint!

program finished with exit code 0