Re: [PAE support] Types + cosmetic fixes

[Eduardo Horvath <eeh%NetBSD.org@localhost>]

On Fri, 26 Feb 2010, Izumi Tsutsui wrote:

> Are you talking about ABI of kernel modules?

That's actually the problem.  We have a kernel driver API, but we do not 
have a kernel driver ABI.  Things like bus_space and bus_dma are 
progamming interfaces but the specific implementation of the interfaces is 
left to the reader.  Most of the time they are implemented as a set of 
macros that operate on data structures hiddend by other macros, due to 
performance claims.  Until each platform defines an interface in terms of 
specific entry points and parameters explitly laid out in registers or 
memory, you don't really have an ABI.

Has anybody actually gone through the kernel code and defined a specific 
set of routines for use by drivers, or is it still open season for 
anything in the kernel?  I don't recall having seen anything like that.

(Adding some sort of versioning to the interfaces would also be good, that 
way a kernel could refuse to load an old, incompatible module, or better 
yet, redirect the module interfaces through compatibility glue.)

Eduardo