Linked by David Adams on Wed 24th Aug 2005 07:21 UTC, submitted by jeanmarc
OSNews, Generic OSes Start-up XenSource has succeeded in booting Microsoft Windows on top of Xen software, an important milestone in its effort to commercialize the virtual machine.
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16 bits?
by evert on Wed 24th Aug 2005 12:26 UTC
evert
Member since:
2005-07-06

"For example, the (Windows XP) boot process uses 16-bit code from that must be emulated on today's 32-bit and 64-bit chips"

unbelievable, isn't it?

Reply Score: 1

RE: 16 bits?
by Mark Williamson on Wed 24th Aug 2005 14:55 in reply to "16 bits?"
Mark Williamson Member since:
2005-07-06

Thing is, any full x86 virtual machine needs to support 16 bit code (e.g. for the bootloader). The difference for Windows is that it *keeps* using 16 bit huring its startup process and you can't bypass it.

Early efforts for VT-enabled Xen just stuck Linux into memory and kicked it into life in protected mode.

Reply Parent Score: 1

RE[2]: 16 bits?
by Mark Williamson on Wed 24th Aug 2005 15:01 in reply to "RE: 16 bits?"
Mark Williamson Member since:
2005-07-06

Actually I think I'll modify that comment: I'm not sure how much Windows expects to use 16 bit mode during kernel startup but in any case I think it *needs* the bootloader to load the various DLLs, registry data etc beforehand. And the bootloader will need to run in 16 bit mode.

Reply Parent Score: 1

RE: 16 bits?
by on Wed 24th Aug 2005 15:04 in reply to "16 bits?"
Member since:

Not really, considering the fact that the bootloader has to be 16-bit for the CPU to run it correctly.

Reply Parent Score: 0