Re: [PATCH] x86_emulate adjustments

[Keir Fraser <keir@xensource.com>]

On 5/1/07 10:03, "Jan Beulich" <jbeulich@novell.com> wrote:

> - don't provide cmpxchg8b emulation where not needed (i.e. page table ops on
> 64-bit hv)

With the cmpxchg16b changes this probably makes sense, despite my dislike of
ifdef if it can be avoided. I'll take a look.

> - properly deal with stack operands (push/pop)

I already got the mis-emulation of x86/64 PUSH/POP with operand-size
override. The stacksz thing I would do differently -- extend the mode input
field to have an extra stack-address-size field. There's another thing
that's not right at the moment -- I think on POP we have to calculate the
operand effective address after adjusting the stack pointer? That is broken
right now which is not a good thing. :-)

> - synchronize prefix handling with hvm's instrlen determination and about to
> be committed privileged op decoder (changes coming with the 32on64 patches)

The whole lot of hvm_instrlen/mmio/privop emulators are all going to get
merged into x86_emulate(). So sync'ing is not really worthwhile, unless
there are bugs in x86_emulate()'s prefix decoder.

> - support cmpxchg16b if the CPU supports it

I'll take a look at this part. Sounds sensible.

 Thanks,
 Keir