[Qemu-devel] Re: [PATCH 1/2] Move KVM init to arch_init.c, compile vl.c once

[Paolo Bonzini <pbonzini@redhat.com>]

On 04/01/2010 10:07 PM, Blue Swirl wrote:
> Remove dependency of vl.c to KVM, then we can partially revert
> b33612d03540fda7fa67485f1c20395beb7a2bf0.

This is ugly...

Michael Tsirkin said in commit ca821806:

  Comment on kvm usage: rather than require users to do if(kvm_enabled())
  and/or ifdefs, this patch adds an API that, internally, is defined to
  stub function on non-kvm build, and checks kvm_enabled for non-kvm
  run.

  While rest of qemu code still uses if (kvm_enabled()), I think this
  approach is cleaner, and we should convert rest of code to it
  long term.

Maybe we can start doing this for kvm_init?

> +void enable_kvm(void)
> +{
> +    kvm_allowed = 1;
> +}

If you're adding this, this conditional from vl.c

  if (!(kvm_available())) {
      printf("Option %s not supported for this target\n", popt->name);
      exit(1);
  }

belongs in arch_init.c too, like in do_smbios_option and 
do_acpitable_option.

Alternatively, with the approach I gave above, you can test in 
kvm_maybe_init if kvm_init returns -ENOSYS, and print the error above 
instead of "failed to initialize KVM".

Paolo