[ros-kernel] VFAT Optimalizations

[Hartmut Birr]

Hi,    

on my second test pc (celeron with 466Mhz and 128MB RAM), compiling ros on
ros does crash always at the same position. It occurs at the point where
shellclass.c from explorer is compiled. The crash occurs at the end of
MmRequestPageMemoryConsumer. It seems that MmAllocPage does return no page.
I revert my ntoskrnl changes and try it again.    

- Hartmut