Hi,
On Fri, 2006-11-10 at 22:39 +0800, Jiang, Yunhong wrote:
> This patch caused one problem.
>
> If the guest change the DS/SS etc between it set cr0.PE and the jump
> instruction.
Hmm... Do you know how much of a problem that causes in practice?
Which guests have that behaviour?
> Considering following code:
> mov eax, cr0
> or eax, 0x11
> mov cr0, eax ---> here enable PE, and old_ctx.ds is cleard
> mov ax, 0x0020
> mov ds, ax -> changes the DS here
Well, we've got commit log comments for the "pop %es" case:
2) In
current vmxassist, when entering VM86_PROTECTED_TO_REAL, we need to
decode every instruction manually until we catch instructions like
jmpl to reset cs to really return to real mode.
So I'm afraid I just assumed that we wouldn't need to deal with ds in
real life, since we haven't added emulation for that so far. Is that
emulation we need to add as a matter of some urgency, then?
--Stephen
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