Arch系统更新后Macbook Air 2012 Wi-Fi故障求助（broadcom-wl-dkms驱动）

Hey there, sorry to hear your Wi-Fi stopped working after updating Arch on your 2012 Macbook Air—let’s troubleshoot this step by step. Broadcom drivers can be finicky after kernel updates, so here’s what to try:

1. 先重启到最新内核 #

System updates often include a new kernel, but if you didn’t reboot after updating, your system might still be running the old one while the broadcom-wl-dkms driver was compiled for the new kernel. A quick reboot can fix this immediately.

2. 验证内核头文件与dkms模块状态 #

DKMS relies on matching kernel headers to compile drivers correctly. Let’s check if everything is aligned:

• First, get your currently running kernel version:

  uname -r
  

• Install the matching kernel headers (if missing):

  sudo pacman -S linux-headers=$(uname -r)
  

• Check the status of the broadcom-wl DKMS module:

  dkms status
  

  You should see an entry like broadcom-wl, <version>, <your-kernel-version>, x86_64: installed. If it says built but not installed, or the kernel version doesn’t match your running one, proceed to recompile.

3. 重新编译并安装broadcom-wl-dkms模块 #

If the module is misaligned with your kernel, force a rebuild:

• First, remove the existing DKMS module:

  sudo dkms remove broadcom-wl --all
  

• Reinstall the driver package to trigger a fresh DKMS build:

  sudo pacman -S --reinstall broadcom-wl-dkms
  

• Load the module manually (if it doesn’t load automatically):

  sudo modprobe wl
  

4. 检查冲突模块 #

Sometimes other Broadcom modules (like brcmsmac or b43) can conflict with wl. Let’s blacklist them to prevent interference:

• Edit the blacklist file:

  sudo nano /etc/modprobe.d/blacklist-broadcom.conf
  

• Add these lines:

  blacklist b43
  blacklist b43legacy
  blacklist brcmsmac
  blacklist bcma
  

• Save the file (Ctrl+O, Enter) and exit (Ctrl+X), then reboot to apply changes.

5. 验证Wi-Fi服务状态 #

Finally, make sure the NetworkManager service is running (assuming you use it):

sudo systemctl enable --now NetworkManager
sudo systemctl restart NetworkManager

Then check if your Wi-Fi interface appears with ip link show.

If none of these steps work, you can dig into system logs for more clues with journalctl -k | grep wl—this will show specific errors when the wl module tries to load.

内容的提问来源于stack exchange，提问作者Toothrot