Re: [PATCH] KVM : Set success rflags when emulate VMXON/VMXOFF in nested virt

[Jan Kiszka <jan.kiszka@web.de>]

[-- Attachment #1: Type: text/plain, Size: 4595 bytes --]

On 2013-07-03 18:05, Arthur Chunqi Li wrote:
> Set success rflags after emulating VMXON/VMXOFF in nested environment.
> 
> Re-arrange the code sequence of 3 functions,
> nested_vmx_succeed()/failValid()/failInvalid(), to avoid double
> declaration in the same file.

Just don't forget to provide corresponding test cases. But you can
collect trivial checks like these and do a single VMX startup/shutdown
test case that consists of several smaller test steps.

Jan

> 
> Signed-off-by: Arthur Chunqi Li <yzt356@gmail.com>
> ---
>  arch/x86/kvm/vmx.c |   85 ++++++++++++++++++++++++++--------------------------
>  1 file changed, 42 insertions(+), 43 deletions(-)
> 
> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> index 260a919..423bc411 100644
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -5551,8 +5551,47 @@ static void nested_free_all_saved_vmcss(struct vcpu_vmx *vmx)
>  		free_loaded_vmcs(&vmx->vmcs01);
>  }
>  
> +/*
> + * The following 3 functions, nested_vmx_succeed()/failValid()/failInvalid(),
> + * set the success or error code of an emulated VMX instruction, as specified
> + * by Vol 2B, VMX Instruction Reference, "Conventions".
> + */
> +static void nested_vmx_succeed(struct kvm_vcpu *vcpu)
> +{
> +	vmx_set_rflags(vcpu, vmx_get_rflags(vcpu)
> +			& ~(X86_EFLAGS_CF | X86_EFLAGS_PF | X86_EFLAGS_AF |
> +			    X86_EFLAGS_ZF | X86_EFLAGS_SF | X86_EFLAGS_OF));
> +}
> +
> +static void nested_vmx_failInvalid(struct kvm_vcpu *vcpu)
> +{
> +	vmx_set_rflags(vcpu, (vmx_get_rflags(vcpu)
> +			& ~(X86_EFLAGS_PF | X86_EFLAGS_AF | X86_EFLAGS_ZF |
> +			    X86_EFLAGS_SF | X86_EFLAGS_OF))
> +			| X86_EFLAGS_CF);
> +}
> +
>  static void nested_vmx_failValid(struct kvm_vcpu *vcpu,
> -				 u32 vm_instruction_error);
> +					u32 vm_instruction_error)
> +{
> +	if (to_vmx(vcpu)->nested.current_vmptr == -1ull) {
> +		/*
> +		 * failValid writes the error number to the current VMCS, which
> +		 * can't be done there isn't a current VMCS.
> +		 */
> +		nested_vmx_failInvalid(vcpu);
> +		return;
> +	}
> +	vmx_set_rflags(vcpu, (vmx_get_rflags(vcpu)
> +			& ~(X86_EFLAGS_CF | X86_EFLAGS_PF | X86_EFLAGS_AF |
> +			    X86_EFLAGS_SF | X86_EFLAGS_OF))
> +			| X86_EFLAGS_ZF);
> +	get_vmcs12(vcpu)->vm_instruction_error = vm_instruction_error;
> +	/*
> +	 * We don't need to force a shadow sync because
> +	 * VM_INSTRUCTION_ERROR is not shadowed
> +	 */
> +}
>  
>  /*
>   * Emulate the VMXON instruction.
> @@ -5612,6 +5651,7 @@ static int handle_vmon(struct kvm_vcpu *vcpu)
>  	vmx->nested.vmxon = true;
>  
>  	skip_emulated_instruction(vcpu);
> +	nested_vmx_succeed(vcpu);
>  	return 1;
>  }
>  
> @@ -5696,6 +5736,7 @@ static int handle_vmoff(struct kvm_vcpu *vcpu)
>  		return 1;
>  	free_nested(to_vmx(vcpu));
>  	skip_emulated_instruction(vcpu);
> +	nested_vmx_succeed(vcpu);
>  	return 1;
>  }
>  
> @@ -5752,48 +5793,6 @@ static int get_vmx_mem_address(struct kvm_vcpu *vcpu,
>  	return 0;
>  }
>  
> -/*
> - * The following 3 functions, nested_vmx_succeed()/failValid()/failInvalid(),
> - * set the success or error code of an emulated VMX instruction, as specified
> - * by Vol 2B, VMX Instruction Reference, "Conventions".
> - */
> -static void nested_vmx_succeed(struct kvm_vcpu *vcpu)
> -{
> -	vmx_set_rflags(vcpu, vmx_get_rflags(vcpu)
> -			& ~(X86_EFLAGS_CF | X86_EFLAGS_PF | X86_EFLAGS_AF |
> -			    X86_EFLAGS_ZF | X86_EFLAGS_SF | X86_EFLAGS_OF));
> -}
> -
> -static void nested_vmx_failInvalid(struct kvm_vcpu *vcpu)
> -{
> -	vmx_set_rflags(vcpu, (vmx_get_rflags(vcpu)
> -			& ~(X86_EFLAGS_PF | X86_EFLAGS_AF | X86_EFLAGS_ZF |
> -			    X86_EFLAGS_SF | X86_EFLAGS_OF))
> -			| X86_EFLAGS_CF);
> -}
> -
> -static void nested_vmx_failValid(struct kvm_vcpu *vcpu,
> -					u32 vm_instruction_error)
> -{
> -	if (to_vmx(vcpu)->nested.current_vmptr == -1ull) {
> -		/*
> -		 * failValid writes the error number to the current VMCS, which
> -		 * can't be done there isn't a current VMCS.
> -		 */
> -		nested_vmx_failInvalid(vcpu);
> -		return;
> -	}
> -	vmx_set_rflags(vcpu, (vmx_get_rflags(vcpu)
> -			& ~(X86_EFLAGS_CF | X86_EFLAGS_PF | X86_EFLAGS_AF |
> -			    X86_EFLAGS_SF | X86_EFLAGS_OF))
> -			| X86_EFLAGS_ZF);
> -	get_vmcs12(vcpu)->vm_instruction_error = vm_instruction_error;
> -	/*
> -	 * We don't need to force a shadow sync because
> -	 * VM_INSTRUCTION_ERROR is not shadowed
> -	 */
> -}
> -
>  /* Emulate the VMCLEAR instruction */
>  static int handle_vmclear(struct kvm_vcpu *vcpu)
>  {
> 



[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 263 bytes --]