tags:

views:

344

answers:

4
+2  Q: 

How do we shift from protected mode to real mode in Linux 2.6?

How do we shift from protected mode to real mode in Linux 2.6?

A: 

The ELKS Linux port can do real mode, but its nowhere near 2.6.

dsm  2009-05-06 13:40:33
+9  A: 

You do not.

The kernel cannot function at all in real mode, nor can bios calls be (sensibly) made, so you wouldn't be able to do anything anyway.

You might look at how DosEMU uses v86 mode to run your "real mode" code, but that's all.

MarkR  2009-05-06 14:48:28
+1  A: 

You could also take a look at FreeDOS if you really need real mode on the hardware.

supercheetah  2009-05-06 16:55:49
+1  A: 

The kernel switches from real mode to protected mode during the very beginning of the boot/start sequence and there is no turning back. See How Boot Loaders Work for more detailed information.

If you have some program that needs real mode, there is v86 mode. Some work is ongoing to add support for this in 64 bit mode.

hlovdal  2009-05-06 22:13:16

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