Hi!
I am building a locked down system based on a stripped desktop Ubuntu distribution. No desktop environment, just the X server, and my kiosk-like application running on top.

When looking around in the kernel config for the most recent kernel in Ubuntu 8.04 (2.6.24.6), I noticed the parameter CONFIG_PNP, "plug and play support".

If I were to compile the kernel, having CONFIG_PNP set to "No", what would be the implications? What would my application have to do in order to, for example, recognize a usb printer attached to the machine?

My main reason for disabling plug and play would be security and stability, and also to keep things as simple as possible.

Regards,
Fredrik

I think this will mean that plug and play devices might not work at all "in the PnP way" with such a system which has a kernel without any PnP support.

I think though the device will still work, if you configure it manually...

With such a kernel, you'll probably need to somehow determine "by hand" such devices' IRQ, DMA and memory range settings (which would have been automatically handled by the PnP interface), and then manually compose a modprobe statement for that device's module that will load such a device's driver and make it usable.

I once had such a situation in an older 2.4 kernel which did not have any PnP support. I had to start the system in Windows, use the Windows tape drive (the PnP device was a tape drive) software to get the IRQ, DMA and memory range settings picked by the Windows PnP driver for the device. I then had to reboot into Linux, and manually use these settings (written on a piece of paper!) to insmod the Linux driver for the tape drive.

The mess was that each time the system had been physically switched off, I had to redo the whole "boot Windows, write down on a piece of paper, reboot into Linux" dance to get the device to work. It was long ago, but it worked for the rare occassions when I needed to be able to access the PnP tape drive in Linux.