Re: [PATCH] UefiCpuPkg/PiSmmCpu: Check XdSupport before set NX.

["Fan, Jeff" <jeff.fan@intel.com>]

Reviewed-by: Jeff Fan <jeff.fan@intel.com>

-----Original Message-----
From: Laszlo Ersek [mailto:lersek@redhat.com] 
Sent: Thursday, November 17, 2016 11:58 PM
To: Yao, Jiewen; edk2-devel@ml01.01.org
Cc: Kinney, Michael D; Fan, Jeff
Subject: Re: [edk2] [PATCH] UefiCpuPkg/PiSmmCpu: Check XdSupport before set NX.

On 11/17/16 14:33, Jiewen Yao wrote:
> When XD is not supported, the BIT63 is reserved.
> We should not set BIT63 in the page table.
> 
> Test OVMF IA32/IA32X64 with XD enabled/disabled.
> 
> Analyzed-by: Laszlo Ersek <lersek@redhat.com>
> Cc: Laszlo Ersek <lersek@redhat.com>
> Cc: Jeff Fan <jeff.fan@intel.com>
> Cc: Michael D Kinney <michael.d.kinney@intel.com>
> Cc: Laszlo Ersek <lersek@redhat.com>
> Contributed-under: TianoCore Contribution Agreement 1.0
> Signed-off-by: Jiewen Yao <jiewen.yao@intel.com>
> ---
>  UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c b/UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c
> index b4f8861..c85e025 100644
> --- a/UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c
> +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c
> @@ -209,10 +209,12 @@ ConvertPageEntryAttribute (
>      }
>    }
>    if ((Attributes & EFI_MEMORY_XP) != 0) {
> -    if (IsSet) {
> -      NewPageEntry |= IA32_PG_NX;
> -    } else {
> -      NewPageEntry &= ~IA32_PG_NX;
> +    if (mXdSupported) {
> +      if (IsSet) {
> +        NewPageEntry |= IA32_PG_NX;
> +      } else {
> +        NewPageEntry &= ~IA32_PG_NX;
> +      }
>      }
>    }
>    *PageEntry = NewPageEntry;
> 

Tested-by: Laszlo Ersek <lersek@redhat.com>

Thanks!
Laszlo