[rhelv6-list] Info on kernel module priority when different one with same name

[Red Hat Enterprise Linux 6 (Santiago) discussion mailing-list]

Red Hat Enterprise Linux 6 (Santiago) discussion mailing-list wrote:
> Hello,
> I'm testing an updated be2net kernel module provided by HP on their driver
> page.
> The system is 6.2 and I built be2net version 4.1.450.7 as it seems it is
> required for a virtual connect upgrade where the physical HP blade is.
> 
> My kernel is 2.6.32-220.4.2 and comes with be2net driver 4.0.160r .
> The latest available from Red Hat is 2.6.32-279.19.1 that contains 4.1.307r
> 
> Reading depmod docs I see that currently I have (default) configuration:
> 
> /etc/depmod.d/dist.conf
> search updates extra built-in weak-updates
> 
> Is it correct to say that this mean that if the HP rpm binary I built
> installs  be2net.ko in extra, I'm ok without doing anything?

Correct.  We use precisely this same module at work (compiled from source
for each kernel version we use), and installing the RPM means it 'just
works'.

> And that if I want to test the two ones and sometimes to revert to old
> driver loading without removing the HP one, I can then add when I need it
> the line:
> 
> override be2net * built-in
> ?

We've never tried this, largely because we've found that the HP module works
better than the RedHat-supplied module (largely surrounding firmware
updates).  In theory, I think this would do what you want.

Note that we've found some issues in the past with running a module built
for a different (read: older) kernel version, where, IIRC, the kernel will
prefer the RedHat-supplied driver.  To work around any wonkiness, we simply
custom-compile the module for every kernel, and drop it into our internal
yum repository.