Re: [Qemu-devel] Re: POLL: Why do you use kqemu?

[Avi Kivity <avi@redhat.com>]

Andreas Färber wrote:
>>
>> You don't have to, it builds against the distro kernel's devel package
>> (I'm doing most KVM development on boring distro kernels). No black
>> magic involved. Really.
>
> Consider me Joe User in that aspect: I have a fairly recent amd64 
> Linux machine, with all the latest security, bugfix and enhancement 
> updates installed.

Joe would just use the packaged qemu from his distro.  That happens to 
be built from qemu-kvm.git, so Joe is already way ahead of you.

>
> $ uname -a
> Linux redhead 2.6.27.24-170.2.68.fc10.x86_64 #1 SMP Wed May 20 
> 22:47:23 EDT 2009 x86_64 x86_64 x86_64 GNU/Linux
> $ ./configure
> [...]
> #error Missing KVM capability KVM_CAP_DESTROY_MEMORY_REGION_WORKS

Like I said, try qemu-kvm.git.

>
> A package search for kvm results in kvm-74-10.fc10 being installed 
> (plus another one with ROMs). There is no additional kvm-kmod package 
> offered that I could install. What should I do?
>
> I could try qemu-kvm.git, yes, but for one thing Anthony has been 
> insistant that patches be made against upstream qemu.git and for 
> another it makes me dependent on someone merging KVM-unrelated commits 
> (like sparc) into qemu-kvm.git, so it doesn't sound like a longterm 
> solution.

I also insist on it.  Try 'git log' on qemu-kvm.git to see why.

>
> There are at least two solutions:
>
> i) Make configure hint users what to do. (README just references 
> qemu-doc.html, which is not yet built and doesn't contain anything 
> helpful here anyway.) Other options are even less verbose though (e.g. 
> Documentation). Building a new kernel or kernel module is not always 
> an option.

Agree.

>
> ii) Merge the apparently existant workarounds upstream. I thought this 
> was the overall plan anyway? Has this changed, like the original plan 
> of Glauber's kqemu-friendly qemu-accel abstraction?

It hasn't changed, it's just moving at a snail's pace.

> Sourceforge (the KVM download link) appears to be down currently btw. 
> Savannah is not the only one with problems, it seems.

Seems to be up now.

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.