Re: [RFT] kvm with Windows optimization

Anthony Liguori
2007-10-26T13:20:15Z

Dong, Eddie wrote:
>> BTW, is it wise to enable this by default for all guests?
>> Ignoring the
>> fact that we're modifying guest's memory without its knowledge, if a
>> guest unmaps the VA mappings for the BIOS then all sorts of problems
>> could occur.
>>
>>
> Good movement!
>
> But, Vista won't work with patching. The memory guard in vista
> will make the system refuse to service. Maybe we need a option
> to check if it is vista.
>

Are you sure that Vista isn't just verifying memory during
startup/driver load? Seems odd to periodically scan memory.

In the recently released Windows Hypervisor specification, in section
13.2.2 (Local APIC Memory-mapped Accesses), it's dictated that the APIC
can only be accessed through 6 instructions. They are all >= 5 byte
instructions. When I first saw that, I figured they were also patching.

Regards,

Anthony Liguori

> Eddie