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Text-based interaction with Linux generally occurs using a TTY, which is connected to and authenticated with getty and login. How are the most early boot messages displayed on a monitor? Does the graphics card driver create a TTY for the early boot messages? I know when I boot an embedded system these messages appear on a serial console, which as far as I know, is a type of TTY.

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/dev/console is used.

Lookup the register_console() function in the kernel source: http://lxr.free-electrons.com/source/kernel/printk/printk.c#L2437

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    This is a good starting point and I will accept this answer if you can add some more information. E.g. how does register_console work with a display driver? Does a display driver call register_console after it is initialized? Does grub or u-boot inform the kernel of the name of the console e.g. fb0 or ttyX to output the boot messages to? What is the relationship between the dev entry and the register_console function? – allsey87 Apr 26 '17 at 9:24

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