I have seen posts and tutorials dealing with updating the kernel, such as this one, but they all expect you to remove the SD card, rewrite it outside with a card reader and then plug it back in. Is it possible to update the kernel without removing the sd card? And if not, why not?
I guess a bootloader such as U-boot could be used for this but I would like to use the native raspberry bootloader if possible. My end goal is to cross compile the kernel in my main computer and send the compiled kernel to my raspberry pi through the network. Are there any alternatives for this? Any help would be immensely appreciated.