Still I am facing the instance available when trying to unload the kext.

[expoinfy]

Hi Slava,

I loaded the module in yosemite osx. And when trying to unload the kext it is saying Can't unload kext com.SlavaImameev.FsdFilter; classes have instances: Below are the command outputs.

Yosmite:user$ sudo kextunload FsdFilter.kext
(kernel) Can't unload kext com.SlavaImameev.FsdFilter; classes have instances:
(kernel) Kext com.SlavaImameev.FsdFilter class FltVnodeHookEntry has 5 instances.
(kernel) Kext com.SlavaImameev.FsdFilter class com_FsdFilter has 1 instance.
(kernel) Kext com.SlavaImameev.FsdFilter class FltIOKitKAuthVnodeGate has 1 instance.
Failed to unload com.SlavaImameev.FsdFilter - (libkern/kext) kext is in use or retained (cannot unload).

Thanks Bhagaban

[slavaim]

It was made non-unloadable. If you need to unload you must correctly implement all cleanup, unhooking and synchronization and remove a reference to the class object taken in com_FsdFilter::start

this->retain();