How can I build a kernel module on one system for a diff. kernel on a diff. system?

business_kid · 09-14-2014, 03:31 AM

Hmmph, forgot that. Further, if you do that (which can be done) you get a possible clash in version magic when you try to boot the thing.

Best to install your new kernel, and reboot on it. It will behave the same as your old one.

Code:

cd /usr/src/linux-<version1>
cp arch/x86/boot/bzImage /boot/vmlinux-<version2>
cp System.map /boot/System.map-<version2>
cp .config /boot/config-<version2>

You need to fill in version1 and version2
version1 is the stuff after 'linux' in the /usr/src directory. Something like -3.14.5

There is a CONFIG_LOCALVERSION setting in the config. It installs and adds this local version on the end. My box has '-6' as a LOCALVERSION, so the modules are in /lib/modules/3.14.5-6. That is <version2>. It often is the same as version1 (if local version is blank)

Now do your thing on grub or lilo, boot the new kernel, and compile the realtek module. The new kernel will have the module - not the old one.

slacker_ · 09-15-2014, 01:05 AM

Ok, so if I do this, and get the module built into this kernel, can I then copy the module and take it to the physical machine this whole project has been for? Or do I need this new kernel on the physical machine?

business_kid · 09-15-2014, 03:08 AM

Now he tells me he is building for another machine :-/.

You may well need the new kernel and modules on the machine with the realtek card. It would have been wise to build there.

onebuck · 09-15-2014, 05:55 PM

Hi,

You can modify the MAKEFILE 'EXTRAVERSION = ' to a unique identifier that would be appended to the new compiled files/directories so that the System install remains the same.

You can then build on another system to move or copy the kernel-version image along with lib-kernel-version to the new system. You would then need to configure the bootloader for the 'new system' to reflect new kernel-version. Any configs for the new kernel-version would need to be copied over and properly linked.
Hope this helps.
Have fun & enjoy!