kernel linker: Overriding a driver shipped with kernel via module?

John-Mark Gurney jmg at funkthat.com
Wed Nov 19 00:36:46 UTC 2014


Slawa Olhovchenkov wrote this message on Wed, Nov 19, 2014 at 04:27 +0400:
> On Tue, Nov 18, 2014 at 04:15:10PM -0800, John-Mark Gurney wrote:
> 
> > Slawa Olhovchenkov wrote this message on Tue, Nov 18, 2014 at 16:45 +0400:
> > > On Mon, Nov 17, 2014 at 03:15:29PM -0800, Xin Li wrote:
> > > 
> > > > Right now one can declare version for a module by doing something like:
> > > > 
> > > > MODULE_VERSION(module_name, module_version);
> > > > 
> > > > Sometimes, it may be desirable for a vendor to release a new driver
> > > > that overrides the driver shipped with the kernel itself.  However, it
> > > > seems that the MODULE_VERSION facility would just refuse the module
> > > > when preloaded with kernel.
> > > > 
> > > > Looking at some other vendor drivers, they are using a slightly
> > > > different module name to overcome this limitation.  Is that the only
> > > > way to do it?
> > > 
> > > I think now time to move to modulated kernel and load all drivers
> > > currently present in GENERIC as modules (via loader.conf).
> > 
> > This becomes slightly more difficult for storage drivers which must
> > be loaded at boot time so the you can mount root from it...  But yes,
> > we are interested in methods to make it easier/more automatic for
> > modules to be loaded to support the hardware that is present in a
> > system...
> 
> When loader can load kernel -- loader can load driver module, this is
> not Linux (but yes, loader need plugable and stackable framework for
> access FS -- currenly booting from ZFS over gstripe not allowed).

That isn't the only issue.. another issue is identifing the correct
kernel module(s) to load at boot... iirc, you cannot unload a kernel
module loaded at boot time...

-- 
  John-Mark Gurney				Voice: +1 415 225 5579

     "All that I will do, has been done, All that I have, has not."


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