From mboxrd@z Thu Jan  1 00:00:00 1970
From: Razvan Cojocaru <rzvncj@gmail.com>
Subject: Re: Is it safe to hvm_emulate_one() an MMX instruction?
Date: Wed, 17 Apr 2013 13:40:12 +0300
Message-ID: <516E7C0C.3050808@gmail.com>
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> So do you mean an MMX instruction, or MOVDQU (which is an XMM
> one)? In any event, 4.2 and later should be fine with this particular
> instruction (and a few more move variants), but 4.1.x and earlier
> won't be, nor does the emulator support the whole spectrum of
> MMX, XMM, and AVX instructions.

In this particular case, MOVDQ, but I'm interested in all the mentioned
types of instructions.

What happens when a HVM guest tries to execute such an unsupported
instruction, via the hypervisor calling hvm_emulate_one()? Does
hvm_emulate_one() not return X86EMUL_OKAY - is testing for that enough?


Thanks,
Razvan Cojocaru