Re: [PATCH v2 6/7] x86/hvm: Add SMAP support to HVM guest

[Andrew Cooper <andrew.cooper3@citrix.com>]

On 23/04/14 15:37, Feng Wu wrote:
>  
>      /* Go back and set accessed and dirty bits only if the walk was a
> diff --git a/xen/include/asm-x86/hvm/hvm.h b/xen/include/asm-x86/hvm/hvm.h
> index 74a09ef..8dbb3f0 100644
> --- a/xen/include/asm-x86/hvm/hvm.h
> +++ b/xen/include/asm-x86/hvm/hvm.h
> @@ -257,6 +257,8 @@ int hvm_girq_dest_2_vcpu_id(struct domain *d, uint8_t dest, uint8_t dest_mode);
>      (hvm_paging_enabled(v) && ((v)->arch.hvm_vcpu.guest_cr[4] & X86_CR4_PAE))
>  #define hvm_smep_enabled(v) \
>      (hvm_paging_enabled(v) && ((v)->arch.hvm_vcpu.guest_cr[4] & X86_CR4_SMEP))
> +#define hvm_smap_enabled(v) \
> +    (hvm_paging_enabled(v) && ((v)->arch.hvm_vcpu.guest_cr[4] & X86_CR4_SMAP))
>  #define hvm_nx_enabled(v) \
>      (!!((v)->arch.hvm_vcpu.guest_efer & EFER_NX))
>  
> @@ -360,6 +362,15 @@ static inline bool_t hvm_vcpu_has_smep(void)
>      return !!(ebx & cpufeat_mask(X86_FEATURE_SMEP));
>  }
>  
> +static inline bool_t hvm_vcpu_has_smap(void)
> +{
> +    unsigned int ebx = 0, leaf = 0x7;
> +
> +    hvm_cpuid(leaf, NULL, &ebx, NULL, NULL);

Same review as the SMEP fix earlier in the series.

~Andrew

> +
> +    return !!(ebx & cpufeat_mask(X86_FEATURE_SMAP));
> +}
> +
>  /* These reserved bits in lower 32 remain 0 after any load of CR0 */
>  #define HVM_CR0_GUEST_RESERVED_BITS             \
>      (~((unsigned long)                          \
> @@ -380,6 +391,7 @@ static inline bool_t hvm_vcpu_has_smep(void)
>          X86_CR4_MCE | X86_CR4_PGE | X86_CR4_PCE |       \
>          X86_CR4_OSFXSR | X86_CR4_OSXMMEXCPT |           \
>          (hvm_vcpu_has_smep() ? X86_CR4_SMEP : 0) |      \
> +        (hvm_vcpu_has_smap() ? X86_CR4_SMAP : 0) |      \
>          (cpu_has_fsgsbase ? X86_CR4_FSGSBASE : 0) |     \
>          ((nestedhvm_enabled((_v)->domain) && cpu_has_vmx)\
>                        ? X86_CR4_VMXE : 0)  |             \