The IG_LOWMEM_CHECK Ioctl operation looks for memory corruption in the low 4 GB of memory.

This Ioctl operation does not take any parameters and the lpvData and cbSizeOfContext parameters should be set to NULL and zero respectively.

Return Value

If no corrupt memory was found, the return value is TRUE; otherwise, it is FALSE.


This operation is only available in kernel-mode debugging, and is only useful when the kernel was started using the /nolowmem option.

When the kernel is started with the /nolowmem option, the kernel, drivers, operating system, and applications are loaded in memory above 4 GB, while the low 4 GB of memory is filled with a unique pattern. The IG_LOWMEM_CHECK Ioctl operation checks this pattern for corruption.

This can be used to verify that a driver works correctly when using physical addresses greater than 32 bits in length. See Physical Address Extension (PAE), /pae, and /nolowmem in the Windows Driver Kit.



Wdbgexts.h (include Wdbgexts.h or Dbgeng.h)



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