I'm working on a kernel driver for a PCIe board. The machine I'm running on has something like 24 cores and a fairly large amount of RAM. It's running RHEL 5.7 with Linux kernel 2.6.18. Sorry, I don't know the exact specs off-hand because it hasn't mattered up until now, and I didn't think to check before I left work today. It's a development machine and my driver (and associated test utils) is the only thing running on it. I won't go into detail about the device or the driver, because those don't seem to be the cause of the problem, but basically the device has 4 separate RS-232 serial interfaces on it, and my driver creates four character devices, with corresponding device nodes in /dev/. The driver also creates numerous sysfs attributes. Some of the attributes are for showing/setting various registers on the board, and the other attributes are actual telemetry data being parsed out of the data received on one of the serial ports. Edit: Come to think of it, the telemetry data sysfs attributes are being created and managed via the hwmon kernel API. Not sure if that might have anything to do with it, but at this point, I have no idea which details may turn out to be important.