Re: [PATCH 10/27] nVMX: Implement VMCLEAR

[Avi Kivity <avi@redhat.com>]

  On 10/17/2010 12:08 PM, Nadav Har'El wrote:
> This patch implements the VMCLEAR instruction.
>
> Signed-off-by: Nadav Har'El<nyh@il.ibm.com>
> ---
>   arch/x86/kvm/vmx.c |   62 ++++++++++++++++++++++++++++++++++++++++++-
>   1 file changed, 61 insertions(+), 1 deletion(-)
>
> --- .before/arch/x86/kvm/vmx.c	2010-10-17 11:52:01.000000000 +0200
> +++ .after/arch/x86/kvm/vmx.c	2010-10-17 11:52:01.000000000 +0200
> @@ -146,6 +146,8 @@ struct __packed vmcs12 {
>   	 */
>   	u32 revision_id;
>   	u32 abort;
> +
> +	bool launch_state; /* set to 0 by VMCLEAR, to 1 by VMLAUNCH */

u32 please, this is an ABI.

>   };
>
>   /*
> @@ -3830,6 +3832,64 @@ static void nested_vmx_failValid(struct
>   	get_vmcs12_fields(vcpu)->vm_instruction_error = vm_instruction_error;
>   }
>
> +/* Emulate the VMCLEAR instruction */
> +static int handle_vmclear(struct kvm_vcpu *vcpu)
> +{
> +	struct vcpu_vmx *vmx = to_vmx(vcpu);
> +	gva_t gva;
> +	gpa_t vmcs12_addr;
> +	struct vmcs12 *vmcs12;
> +	struct page *page;
> +
> +	if (!nested_vmx_check_permission(vcpu))
> +		return 1;
> +
> +	if (get_vmx_mem_address(vcpu, vmcs_readl(EXIT_QUALIFICATION),
> +			vmcs_read32(VMX_INSTRUCTION_INFO),&gva))
> +		return 1;
> +
> +	if (kvm_read_guest_virt(gva,&vmcs12_addr, sizeof(vmcs12_addr),
> +				vcpu, NULL)) {
> +		kvm_queue_exception(vcpu, PF_VECTOR);
> +		return 1;
> +	}
> +
> +	if (!IS_ALIGNED(vmcs12_addr, PAGE_SIZE)) {
> +		nested_vmx_failValid(vcpu, VMXERR_VMCLEAR_INVALID_ADDRESS);
> +		skip_emulated_instruction(vcpu);
> +		return 1;
> +	}
> +
> +	if (vmcs12_addr == vmx->nested.current_vmptr){
> +		kunmap(vmx->nested.current_vmcs12_page);
> +		nested_release_page(vmx->nested.current_vmcs12_page);
> +		vmx->nested.current_vmptr = -1ull;
> +	}
> +
> +	page = nested_get_page(vcpu, vmcs12_addr);
> +	if(page == NULL){

Missing whitespace.

> +		/*
> +		 * For accurate processor emulation, VMCLEAR beyond available
> +		 * physical memory should do nothing at all. However, it is
> +		 * possible that a nested vmx bug, not a guest hypervisor bug,
> +		 * resulted in this case, so let's shut down before doing any
> +		 * more damage:
> +		 */
> +		set_bit(KVM_REQ_TRIPLE_FAULT,&vcpu->requests);
> +		return 1;
> +	}
> +	vmcs12 = kmap(page);

kmap_atomic() please (better, kvm_write_guest(), but can defer that for 
later)

> +	vmcs12->launch_state = 0;
> +	kunmap(page);
> +	nested_release_page(page);
> +
> +	nested_free_vmcs(vcpu, vmcs12_addr);
> +
> +	skip_emulated_instruction(vcpu);
> +	nested_vmx_succeed(vcpu);
> +	return 1;
> +}
> +
>   static int handle_invlpg(struct kvm_vcpu *vcpu)
>   {
>   	unsigned long exit_qualification = vmcs_readl(EXIT_QUALIFICATION);

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