[Qemu-devel] Re: Killing KQEMU

[Avi Kivity <avi@redhat.com>]

Chris Frey wrote:
> On Tue, Jun 02, 2009 at 11:24:11PM +0300, Avi Kivity wrote:
>   
>> Not supporting >2GB guests is a large annoyance (very large if you have 
>> 128GB of RAM).  Don't know about the others.  I think kqemu also blocks 
>> memory hotplug.
>>     
>
> Even if I were to fix kqemu to support such guests, I'd have no way to
> test it, with test machine specs like that.
>
> People say on this list that nobody wants to write for old hardware, but
> kernel developers (and apparently QEMU developers) are so far ahead of
> the curve that they forget that a system with 1GB of RAM may be someone's
> most powerful machine.
>   

You don't need to make kqemu run large guests, just stop it from 
preventing qemu and qemu/kvm from running large guests.  It's perfectly 
reasonable for kqemu to have some limitations.

>> If you're stepping up I can point out the problems I'm aware of.
>>     
>
> I'm most interested in easing the pain of keeping kqemu alive.  It seems
> like valuable tech that should not be thrown away just yet.
>
> What can I, a non-expert, do to help ease the pain that does not involve
> a rewrite or a porting to KVM?  I'm very competent in C and have hacked
> the kernel a bit, but QEMU is new territory.
>   

Start by finding out why kqemu insists on 32-bit page descriptors, and 
increase it to 64 bits.

-- 
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