
Kernel 201 – Let’s write a kernel with keyboard and screen support (2014) - chei0aiV
http://arjunsreedharan.org/post/99370248137/kernel-201-lets-write-a-kernel-with-keyboard?hn
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bobmichael
For beginners, you might want to check out the previous article (Kernel 101)
first [0].

[0]
[http://arjunsreedharan.org/post/82710718100/kernel-101-lets-...](http://arjunsreedharan.org/post/82710718100/kernel-101-lets-
write-a-kernel)

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Animats
Ah, so tempting - putting the device drivers in the kernel. After all, how
else would you start up?

The QNX solution to this is that drivers are always user processes, but you
can put additional programs in the boot image which start at boot. That's how
the first drivers get started. This is valuable for embedded systems, which
may not have a keyboard, screen, or disk drive, but may have other ways to get
info to someplace useful.

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pjc50
It's quite handy that the 30 year old keyboard controller subsystem is still
present. If it wasn't and you had to enumerate USB first that would be a whole
lot more work.

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mtgx
Why give the keyboard and screen access to the kernel? Do you want to get
kernel exploits? Because that's how you get kernel exploits.

