On 25 August 2013 15:48, Gleb Natapov gleb@redhat.com wrote:
On Sun, Aug 25, 2013 at 03:29:17PM +0100, Peter Maydell wrote:
Smiley noted, but this is pretty unlikely since it's not possible to lie to the guest about which mode it's in, so you can't make a guest think it's in Hyp mode.
I suspected this, but forgot most that I read about Hyp mode by now. Need to refresh my memory ASAP. Is it impossible even with a lot of emulation? Can guest detect that it is not in a Hyp mode without trapping into hypervisor?
Yes. The current mode is in the the low bits of the CPSR, which is readable without causing a trap. This is just the most obvious roadblock; I bet there are more. If you really had to run Hyp mode code in a VM you probably have to do it by having it all emulated via TCG.
-- PMM