Re: [PATCH 03/27] nVMX: Implement VMXON and VMXOFF

[Avi Kivity <avi@redhat.com>]

  On 10/17/2010 12:05 PM, Nadav Har'El wrote:
> This patch allows a guest to use the VMXON and VMXOFF instructions, and
> emulates them accordingly. Basically this amounts to checking some
> prerequisites, and then remembering whether the guest has enabled or disabled
> VMX operation.
>
>
> +/*
> + * Emulate the VMXON instruction.
> + * Currently, we just remember that VMX is active, and do not save or even
> + * inspect the argument to VMXON (the so-called "VMXON pointer") because we
> + * do not currently need to store anything in that guest-allocated memory
> + * region. Consequently, VMCLEAR and VMPTRLD also do not verify that the their
> + * argument is different from the VMXON pointer (which the spec says they do).
> + */
> +static int handle_vmon(struct kvm_vcpu *vcpu)
> +{
> +	struct kvm_segment cs;
> +	struct vcpu_vmx *vmx = to_vmx(vcpu);
> +
> +	/* The Intel VMX Instruction Reference lists a bunch of bits that
> +	 * are prerequisite to running VMXON, most notably CR4.VMXE must be
> +	 * set to 1. Otherwise, we should fail with #UD. We test these now:
> +	 */
> +	if (!nested ||

Is the !nested case needed?  Presumably cr4.vmxe will be clear is !nested.

> +	    !kvm_read_cr4_bits(vcpu, X86_CR4_VMXE) ||
> +	    !kvm_read_cr0_bits(vcpu, X86_CR0_PE) ||
> +	    (vmx_get_rflags(vcpu)&  X86_EFLAGS_VM)) {
> +		kvm_queue_exception(vcpu, UD_VECTOR);
> +		return 1;
> +	}
> +
> +	vmx_get_segment(vcpu,&cs, VCPU_SREG_CS);
> +	if (is_long_mode(vcpu)&&  !cs.l) {
> +		kvm_queue_exception(vcpu, UD_VECTOR);
> +		return 1;
> +	}
> +
> +	if (vmx_get_cpl(vcpu)) {
> +		kvm_inject_gp(vcpu, 0);
> +		return 1;
> +	}
> +
> +	vmx->nested.vmxon = true;
> +
> +	skip_emulated_instruction(vcpu);
> +	return 1;
> +}
>

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