Reducing the need to compile a custom kernel

Bjoern A. Zeeb bzeeb-lists at
Fri Feb 10 16:15:05 UTC 2012

On 10. Feb 2012, at 13:56 , Alexander Leidinger wrote:

> Hi,
> during some big discussions in the last monts on various lists, one of the problems was that some people would like to use freebsd-update but can't as they are using a custom kernel. With all the kernel modules we provide, the need for a custom kernel should be small, but on the other hand, we do not provide a small kernel-skeleton where you can load just the modules you need.
> This should be easy to change. As a first step I took the generic kernel and removed all devices which are available as modules, e.g. the USB section consists now only of the USB_DEBUG option (so that the module is build like with the current generic kernel). I also removed some storage drivers which are not available as a module. The rationale is, that I can not remove CAM from the kernel config if I let those drivers inside (if those drivers are important enough, someone will probably fix the problem and add the missing pieces to generate a module).

And you completely seem to have missed the discussion about a device ID DB and loader being able to probe and load them for you?

With that sound, firewire, but also NICs and storage drivers can mostly go away...  But it needs infrastructure... lots of ... feel free to resume that thread but stable@ is obviously the wrong place.

> Such a kernel would cover situations where people compile their own kernel because they want to get rid of some unused kernel code (and maybe even need the memory this frees up).
> The question is, is this enough? Or asked differently, why are you compiling a custom kernel in a production environment (so I rule out debug options zhich are not enabled in GENERIC)? Are there options which you add which you can not add as a module (SW_WATCHDOG comes to my mind)? If yes, which ones and how important are they for you?

As a lot of the results will show... various parts of the network stack being loadable, which is not as easy as it sounds, especially making them unloadable again currently ...


Bjoern A. Zeeb                                 You have to have visions!
   It does not matter how good you are. It matters what good you do!

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