Re: [PATCH] KVM: VMX: Add PAT support for EPT

[Avi Kivity <avi@qumranet.com>]

Sheng Yang wrote:


(some text wanted here)

> diff --git a/arch/x86/kvm/vmx.h b/arch/x86/kvm/vmx.h
> index 0c22e5f..16b3cfb 100644
> --- a/arch/x86/kvm/vmx.h
> +++ b/arch/x86/kvm/vmx.h
> @@ -62,11 +62,14 @@
>  #define PIN_BASED_VIRTUAL_NMIS                  0x00000020
>  
>  #define VM_EXIT_HOST_ADDR_SPACE_SIZE            0x00000200
> +#define VM_EXIT_LOAD_GUEST_PAT			0x00004000
>  #define VM_EXIT_ACK_INTR_ON_EXIT                0x00008000
>  
>  #define VM_ENTRY_IA32E_MODE                     0x00000200
>  #define VM_ENTRY_SMM                            0x00000400
>  #define VM_ENTRY_DEACT_DUAL_MONITOR             0x00000800
> +#define VM_ENTRY_SAVE_GUEST_PAT			0x00040000
> +#define VM_ENTRY_LOAD_HOST_PAT			0x00080000
>  
>  /* VMCS Encodings */
>  enum vmcs_field {
> @@ -112,6 +115,8 @@ enum vmcs_field {
>  	VMCS_LINK_POINTER_HIGH          = 0x00002801,
>  	GUEST_IA32_DEBUGCTL             = 0x00002802,
>  	GUEST_IA32_DEBUGCTL_HIGH        = 0x00002803,
> +	GUEST_PAT			= 0x00002804,
> +	GUEST_PAT_HIGH			= 0x00002805,
>  	GUEST_PDPTR0                    = 0x0000280a,
>  	GUEST_PDPTR0_HIGH               = 0x0000280b,
>  	GUEST_PDPTR1                    = 0x0000280c,
> @@ -120,6 +125,8 @@ enum vmcs_field {
>  	GUEST_PDPTR2_HIGH               = 0x0000280f,
>  	GUEST_PDPTR3                    = 0x00002810,
>  	GUEST_PDPTR3_HIGH               = 0x00002811,
> +	HOST_PAT			= 0x00002c00,
> +	HOST_PAT_HIGH			= 0x00002c01,
>  	PIN_BASED_VM_EXEC_CONTROL       = 0x00004000,
>  	CPU_BASED_VM_EXEC_CONTROL       = 0x00004002,
>  	EXCEPTION_BITMAP                = 0x00004004,
>   

This appears to be a new feature?  My documentation (a bit old) doesn't 
show it.  If so, we need a check to see that it is available.

An alternative to switching PAT is to translate a guest PAT index into a 
host PAT index.  But I guess that doesn't work with EPT?

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