Re: Over-riding symbols in the Kernel causes Kernel Panic

[Bill Davidsen <davidsen@tmr.com>]

Ashutosh Naik wrote:
> Hi,
> 
> I made e1000 ( or for that matter anything) a part of the 2.6.15-rc1
> kernel and booted the kernel. Next I compiled e1000 as a module (
> e1000.ko ), and tried to insmod it into the kernel( which already had
> e1000 a compiled as a part of the kernel). I observed that
> /proc/kallsyms contained two copies of all the symbols exported by
> e1000, and I also got a Kernel Panic on the way.
> 
> Is this behaviour natural and desirable ?

No, trying to insert a module into a kernel built with the functionality 
compiled in is a vile perverted act, and probably illegal in Republican 
states! ;-)

The other day I mentioned that reiser4 will find bugs because people 
will do bizarre things with it when it is more widely used. I think you 
have hit a "no one would ever do that" bug in the module loader, and 
demonstrated my point in the process.

The panic isn't desirable, but I'm not sure what "correct behaviour" 
would be, I can't imagine that this is intended to work. The issues of 
removing such a module gracefully are significant.
-- 
    -bill davidsen (davidsen@tmr.com)
"The secret to procrastination is to put things off until the
  last possible moment - but no longer"  -me