Re: [PATCH 2/2] x86/cpu: Handle GUEST_MAXPHYADDR < HOST_MAXPHYADDR for hosts that don't support it
On 09/07/20 21:13, Eduardo Habkost wrote:
> Doesn't this require intercepting MOV-to-CR3 when the guest
is in PAE
> mode, so that the hypervisor can validate the high bits in the PDPTEs?
If the fix has additional overhead, is the additional overhead
bad enough to warrant making it optional? Most existing
GUEST_MAXPHYADDR < HOST_MAXPHYADDR guests already work today
without the fix.
The problematic case is when host maxphyaddr is 52. That case wouldn't
work at all without the fix.
Paolo