DSP module

I have a situation where I do not know the caused yet. The cmemkk.ko is loaded and working OK. But, for some reason when the userspace application got crashes, the device node for cmemkk (/dev/cmem) is disappeared. The userspace application is not directly connected to cmem, instead it uses the DMAI.

Any idea pointers why /dev/cmem is disappearing?.

Thanks,

John