On Sun, Aug 25, 2013 at 04:18:02PM +0100, Peter Maydell wrote: > On 25 August 2013 15:48, Gleb Natapov <gleb@xxxxxxxxxx> 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. > Or through some highly paravirtualized nested virtualization solution if that is ever relevant. -Christoffer -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html