Re: [PATCH 1/24] Move nested option from svm.c to x86.c

[Avi Kivity <avi@redhat.com>]

On 06/13/2010 03:23 PM, Nadav Har'El wrote:
> The SVM module had a "nested" option, on by default, which controls whether
> to allow nested virtualization. Now that VMX also supports nested
> virtualization, we can move this option to x86.c, for both SVM and VMX.
>
> The "nested" option takes three possible values. 0 disables nested
> virtualization on both SVM and VMX, and 1 enables it on both.
> The value 2, which is the default when this module option is not explicitly
> set, asks each of SVM or VMX to choose its own default; Currently, VMX
> disables nested virtualization in this case, while SVM leaves it enabled.
>
> When nested VMX becomes more mature, this default should probably be changed
> to enable nested virtualization on both architectures.
>
> --- .before/arch/x86/kvm/x86.c	2010-06-13 15:01:28.000000000 +0300
> +++ .after/arch/x86/kvm/x86.c	2010-06-13 15:01:28.000000000 +0300
> @@ -95,6 +95,17 @@ EXPORT_SYMBOL_GPL(kvm_x86_ops);
>   int ignore_msrs = 0;
>   module_param_named(ignore_msrs, ignore_msrs, bool, S_IRUGO | S_IWUSR);
>
> +/* If nested=1, nested virtualization is supported. I.e., the guest may use
> + * VMX or SVM (as appropriate) and be a hypervisor for its own guests.
> + * If nested=0, nested virtualization is not supported.
> + * When nested starts as 2 (which is the default), it is later modified by the
> + * specific module used (VMX or SVM). Currently, nested will be left enabled
> + * on SVM, but reset to 0 on VMX.
> + */
> +int nested = 2;
> +EXPORT_SYMBOL_GPL(nested);
> +module_param(nested, int, S_IRUGO);
> +
>    


A global variable names 'nested' is not a good idea.  I recommend having 
a kvm-intel scope module parameter instead, that also avoids the 0/1/2 
values.

After the patches are merged we can try to consolidate here.

-- 
error compiling committee.c: too many arguments to function