CentOS7 with BCM4311

[backdrum]

Hello, there.

I got an old laptop(HP nx6320) and installed CentOS7 on it. It works fine except wifi.
So I've tried to solve it, I googled. I found out there were some issues with my wifi chip(Broadcom BCM4311).

I followed this link -> https://wiki.centos.org/HowTos/Laptops/ ... s/Broadcom. It's helpful but didn't work for me.
Then I tried this too -> https://tutorialforlinux.com/2019/12/31 ... n-guide/3/. It didn't work either.

On boot, my laptop says like this:
[ 1.836950] wl: loading out-of-tree module taints kernel.
[ 1.836962] wl: module license 'MIXED/Proprietary' taints kernel.
[ 1.836964] Disabling lock debugging due to kernel taint
[ 1.850584] wl: module verification failed: signature and/or required key missing - tainting kernel
[ 1.915082] wl driver 6.30.223.271 (r587334) failed with code 21
[ 1.915087] ERROR @wl_cfg80211_detach : NULL ndev->ieee80211ptr, unable to deref wl

I'm sorry for another BCM issue, but I'm so desperate now.
Please, help me!
(I'm not good at Linux, Network and English, so I need your generous understanding. Thank you!)

[TrevorH]

[ 1.850584] wl: module verification failed: signature and/or required key missing - tainting kernel

Looks like you have secure boot enabled and the kernel module is either not signed or you have not imported the signing key into your UEFI setup.

[backdrum]

Thank you for your reply, (Mr. or Ms.) TrevorH.

I don't think my laptop support UEFI mode. My laptop is a Core2 Duo CPU model; quite old.
In addition to that, I checked BIOS and couldn't find any secure boot option or something like that.(maybe because of my ignorance...)

If you need an image or more information, please, let me know that.

Best Regards,

[TrevorH]

Do you have a /sys/firmware/efi directory?

[backdrum]

There isn't any directory like a '/sys/firmware/efi'.
There are only acpi, dmi, memmap and qemu_fw_cfg, there.