On Fri, Mar 04, 2022, Zeng Guang wrote:
> diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
> index c569dc2b9192..8a5713d49635 100644
> --- a/arch/x86/kvm/vmx/vmx.c
> +++ b/arch/x86/kvm/vmx/vmx.c
> @@ -2422,6 +2422,21 @@ static __init int adjust_vmx_controls(u32 ctl_min, u32 ctl_opt,
> return 0;
> }
>
> +static __init int adjust_vmx_controls_64(u64 ctl_min, u64 ctl_opt,
I slightly prefer controls64 over controls_64. As usual, KVM is inconsistent as
a whole, but vmcs_read/write64 omit the underscore, so we can at least be somewhat
consistent within VMX.
> + u32 msr, u64 *result)
> +{
> + u64 allowed1;
> +
> + rdmsrl(msr, allowed1);
> +
> + /* Ensure minimum (required) set of control bits are supported. */
> + if (ctl_min & ~allowed1)
Eh, just drop @ctl_min. Practically speaking, there is zero chance tertiary
controls or any other control of this nature will ever be mandatory. Secondary
controls would fall into the same boat, but specifying min=0 allows it to share
helpers, so it's the lesser of evils.
With the error return gone, this can be
static __init u64 adjust_vmx_controls64(u64 ctl_opt, u32 msr)
{
u64 allowed;
rdmsrl(msr, allowed);
return ctl_opt & allowed;
}
Alternatively, we could take the control-to-modify directly and have no return,
but I like having the "u64 opt = ..." in the caller.
