Re: [PATCH 18/26] KVM: PPC: KVM PV guest stubs

Alexander Graf
2010-06-28T08:23:09Z

On 28.06.2010, at 10:15, Avi Kivity wrote:

> On 06/28/2010 09:33 AM, Alexander Graf wrote:
>>
>>> Could you do something similar in module_finalize() to patch loaded modules' .text sections?
>>>
>> I could, but do we need it? I objdump -d | grep'ed all my modules and didn't find any need to do so.
>>
>
> You mean even kvm.ko doesn't use privileged instructions?

It does, but I don't think it's worth speeding those up. There are only a couple. Most of the privileged instructions in PPC KVM are statically compiled into the kernel because we need to guarantee they're in the RMO (first 8MB for the PS3).

Even with the magic page in use, trapping instructions still works exactly as before, so we're only talking about a speed difference.

Alex