At 16:37 +0100 on 05 Mar (1614962224), Jan Beulich wrote: > We can't make correctness of our own behavior dependent upon a > hypervisor underneath us correctly telling us the true physical address > with hardware uses. Without knowing this, we can't be certain reserved > bit faults can actually be observed. Therefore, besides evaluating the > number of address bits when deciding whether to use the optimization, > also check whether we're running virtualized ourselves. > > Requested-by: Andrew Cooper <[email protected]> > Signed-off-by: Jan Beulich <[email protected]>
Acked-by: Tim Deegan <[email protected]> I would consider this to be a bug in the underlying hypervisor, but I agree than in practice it won't be safe to rely on it being correct. These checks are getting fiddly now. I think that if we end up adding any more to them it might be good to set a read-mostly variable at boot time rather than do them on every MMIO/NP fault. Cheers, Tim.
