IOKit based kext is visible in kextstat but not in ioreg in 10.13.4

Hi,

I've got iokit based class, that have IOUserClientClass which connected by user-space process using IOServiceGetMatchingService function.

my code looks roughly like this :

KextManagerLoadKextWithURL(driverPath, NULL); // load the driver

classToMatch = IOServiceMatching(MY_USERCLIENT_CLASS);

do {
   CFRetain(classToMatch);  // to be released by  IOServiceGetMatchingService
   serviceObject = IOServiceGetMatchingService(kIOMasterPortDefault, classToMatch);
         
   if (!serviceObject) {
       os_log_info(g_logger, "Waiting for driver to become available");
       sleep(1);
   }
} while (!serviceObject)


IOServiceGetMatchingService(kIOMasterPortDefault, classToMatch); // connect the driver using Client class

However, while trying to deploy the product in 10.13.4, I keep failing IOServiceGetMatchingService method, and only after restart it succeed.

Perhaps there's any way to debug the issue (I don't see anything unusual in the log console.)