sudo apt-mark hold raspberrypi-bootloader
sudo apt-get update
sudo apt-get upgrade
Update bootloader, but not the kernel and modules:
sudo apt-get install rpi-update
sudo SKIP_KERNEL=1 rpi-update ¤ÓÊÑè§ÍÒ¨·ÓäÁèä´éà¾ÃÒÐà¡ÕèÂǡѺ IPv6 ¡Ñº 4 ¹èÒ¨Ðá¡éµÒÁ LINK
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