Re: compat code being included in non-compat kernels?

[Maxime Villard <max%m00nbsd.net@localhost>]

Le 05/03/2018 à 11:43, Paul Goyette a écrit :
> (Unicast, but feel free to share.)
>
> I wonder if, for now, it would make sense just to add compat_mod.c to the
> libcompat.o object?  That would "register" the included code, and other
> modules which already depend on the compat module (such as the
> compat_netbsd32 module) would not try to load another copy.
>
>
> When are you planning on moving forward with your proposed changes? Seems
> like it's time for that next step.   :)

I'm already doing way too many things, and I'm not going to start working on
this. But feel free to take my patches and adapt/commit them.

Basically the final goal is:

 - Have the common compat code, mostly located in compat/common, depend on
   an independent option, like COMPAT_NETBSD or COMPAT_LIB (let's say the
   latter). Something that can be put in, or removed from, GENERIC. This
   common compat code should only provide functions that are used by _other_
   compat modules. These other modules use the functions and may register them
   in the syscall array for example, but the common compat code _does not_
   register its functions. It only provides them.

 - Modify the "compat.kmod" module to build only the aforementioned common
   compat code, and while here rename it to "compat_lib.kmod" (or something
   else) for clarity.

 - Modify the numerous COMPAT_ options to depend on COMPAT_LIB. The result is,
   if you enable only COMPAT_LINUX for example, then COMPAT_LIB gets enabled
   as a dependency, and will compile the common functions.

 - Modify the "compat_*.kmod" modules to dynamically depend on
   "compat_lib.kmod". In such a way that when you modload "compat_linux.kmod",
   if the "compat_lib" dependency is not in the kernel (either because the
   kernel was not compiled with COMPAT_LIB or because compat_lib.kmod was not
   loaded beforehand), then "compat_lib.kmod" is loaded automatically.

At the end the mess is untangled, and we can think about externalizing all of
our compat options into kernel modules.

Maxime