launching windows from vm 8086?

[Jonatan44]

Hello eveyone?
is it possible to switch from real mode to protected mode (e.g booting linux os), then start a vm8086 cpu task, then executing windows boot code and causing windows to start up? of course making linux to disappear.

if not, it there another way to switch from one os to another without power resetting the cpu?

thanks.

[smoothCoder]

I like people who are trying to go above the traditional use of things.
I was asking myself the same question before a few mounth.
I think it will be ease to achieve this, if you load the bootcode of windows in the place where bios loads it normally, then go back real mode, then jmp to the boot code and that is it. I don't know in exactly wich moment linux will be killed.
If you achive the OS1 -> OS2 transition, then you could achieve the OS2 -> OS1 too. If you have initialized any other CPU, you should first halt it properly way.

Good luck!

[Combuster]

If you want to switch OSes, us a virtual machine, or better, a KVM switch Essentially, the v8086 is a partial implementation of the former.

And technically the processor doesn't get powercycled when you reset it from software, it just gets its state wiped. The time you possibly gain on not executing the BIOS is on desktop systems is very small compared to the time you need to boot the OS itself. Plus that doing things that way requires you to put all hardware back into bios-compatible states which is much more error-prone than just letting the bios do that.

[Love4Boobies]

In other words, vm8086 doesn't have a protected mode of its own And even if it did, you couldn't just wipe out the host OS as you'd just be running a task which wouldn't have access to physical memory directly (read up on virtual memory).