[SOLVED] How to safely (re)install Broadcom wireless drivers after kernel upgrade from 4.4.14 to 4.4.261 Slackware 14.2 stable

Today I used 'slackpkg download kernel*' and 'installpkg' to upgrade my kernel from 4.4.14 to 4.4.261.

I want to keep the old kernel around for a few days while I test 4.4.261 with my elderly (12+ year old) Compaq (x86_64 AMD Turion(tm)X2 Dual Core Mobile RM-74)
laptop

To run the wireless card on my laptop I need to use the Broadcom slackbuild drivers/firmware from SlackBuilds.org

These are configured, installed and working on the 4.4.14 kernel. When I boot the new kernel the wireless card is not recognised and I assume I have to install the Broadcom drivers etc. to test out that this will work.

My question is can I boot the 4.4.261 kernel and then install these Broadcom drivers/firmware and run them at the same time as they are on the 4.4.14 kernel? Or do I need to uninstall them from the old kernel first?

Ideally I would like to have them installed simultaneously on both kernel installs so I can boot between the two over the next week or so for testing etc.
Is this possible or will they conflict?

I installed the Broadcom packages from slackbuilds using the slackBuild scripts and then running installpkg in the /tmp folder if that is relevant.

Look into /lib/modules/, you will see subdirectories for kernel modules, separate for each kernel version.

Thank you Emerson,
Broadcom drivers installed on 4.4.261 kernel and wireless working.

I looked in /lib/modules/ and there are separate subdirectories for 4.4.14 and 4.4.261, just as you described, so I've learned something new as well.
Thanks again,
Mikoyan

This is a continuation of the above scenario, I hope it is okay to post here rather than start a new thread.

I installed the broadcom-sta drivers whilst 4.4.261 kernel is running. They work perfectly when booting either kernel.

So no problem until I ran slackpkg upgrade-all and was given the option to ignore, remove or blacklist the double install of drivers. I chose blacklist because I do not want them removed at the moment, as the system is working fine.

I thought the drivers would install into separate kernel modules, (in /lib/modules/, you will see subdirectories for kernel modules, separate for each kernel version.), but clearly I misunderstood, or installed the drivers incorrectly. (I used the slackBuild script from slackBuilds.org).

Can I ignore the warning from slackpkg or should I do something about it? Also, how can I avoid this in the future?

If you have a look in /etc/slackpkg/blacklist
(as root) nano /etc/slackpkg/blacklist

At the end of that file, you'll find something like this...
# This one will blacklist all SBo packages:
#[0-9]+_SBo

If there's a # in front of that line, remove it and re-run slackpkg update, slackpkg install-new, slackpkg upgrade-all

As you are not upgrading kernel by using slackpkg upgrade-all, I'd suggest that you also blacklist the kernel packages

As you'll see once opening the blacklist file, there's instructions there that will guide you.

Thank you for the advice MKDIO,

As you suggested, I have uncommented [0-9]+_SBo in /etc/slackpkg/blacklist and re-ran slackpkg update, slackpkg install-new, slackpkg upgrade-all and there were no error messages this time.

I was forced to start using kernel 4.9 on my acer netbook because of an issue with the touchpad (driver seems to be broken on 4.4 kernel) but on the newer 4.9 kernels the broadcom wl driver source was no longer building.
Apart from the wifi card troubles the netbook is still working fine so I was not yet ready to buy a new one. For some time I considered replacing the mini pci-e card with a supported one but after a little searching I found this on github which is supposed to build for kernels >= 4.7
and so far it's working fine.
Just clone the git repo and then

make clean
make
cp wl.ko /lib/modules/$(uname -r)/kernel/drivers/net/wireless/wl.ko
depmod -a