Re: [Patch V2 01/14] UefiCpuPkg/CpuPageTableLib: Remove unneeded 'if' condition

["duntan" <dun.tan@intel.com>]

Thanks Ray. Will update the copy right year in next version patch.

Thanks,
Dun

-----Original Message-----
From: Ni, Ray <ray.ni@intel.com> 
Sent: Wednesday, March 15, 2023 9:24 AM
To: Tan, Dun <dun.tan@intel.com>; devel@edk2.groups.io
Cc: Dong, Eric <eric.dong@intel.com>; Kumar, Rahul R <rahul.r.kumar@intel.com>; Gerd Hoffmann <kraxel@redhat.com>
Subject: RE: [Patch V2 01/14] UefiCpuPkg/CpuPageTableLib: Remove unneeded 'if' condition

You can carry my Reviewed-by in next version if you add the copy right year change.

> -----Original Message-----
> From: Tan, Dun <dun.tan@intel.com>
> Sent: Wednesday, March 8, 2023 6:08 PM
> To: devel@edk2.groups.io
> Cc: Dong, Eric <eric.dong@intel.com>; Ni, Ray <ray.ni@intel.com>; 
> Kumar, Rahul R <rahul.r.kumar@intel.com>; Gerd Hoffmann 
> <kraxel@redhat.com>
> Subject: [Patch V2 01/14] UefiCpuPkg/CpuPageTableLib: Remove unneeded 
> 'if' condition
> 
> Remove unneeded 'if' condition in CpuPageTableLib code.
> The deleted code is in the code branch for present non-leaf parent 
> entry. So the 'if' check for (ParentPagingEntry->Pnle.Bits.Present
> == 0) is always FALSE.
> 
> Signed-off-by: Dun Tan <dun.tan@intel.com>
> Cc: Eric Dong <eric.dong@intel.com>
> Cc: Ray Ni <ray.ni@intel.com>
> Cc: Rahul Kumar <rahul1.kumar@intel.com>
> Cc: Gerd Hoffmann <kraxel@redhat.com>
> ---
>  UefiCpuPkg/Library/CpuPageTableLib/CpuPageTableMap.c | 9 ---------
>  1 file changed, 9 deletions(-)
> 
> diff --git a/UefiCpuPkg/Library/CpuPageTableLib/CpuPageTableMap.c
> b/UefiCpuPkg/Library/CpuPageTableLib/CpuPageTableMap.c
> index 37713ec659..47027917d9 100644
> --- a/UefiCpuPkg/Library/CpuPageTableLib/CpuPageTableMap.c
> +++ b/UefiCpuPkg/Library/CpuPageTableLib/CpuPageTableMap.c
> @@ -375,15 +375,6 @@ PageTableLibMapInLevel (
>      //            we need to change PDPTE[0].ReadWrite = 1 and let all PDE[0-
> 255].ReadWrite = 0 in this step.
>      //       when PDPTE[0].Nx = 1 but caller wants to map [0-2MB] as Nx = 0
> (PDT[0].Nx = 0)
>      //            we need to change PDPTE[0].Nx = 0 and let all PDE[0-255].Nx = 1 in
> this step.
> -    if ((ParentPagingEntry->Pnle.Bits.Present == 0) && (Mask->Bits.Present
> == 1) && (Attribute->Bits.Present == 1)) {
> -      if (Modify) {
> -        ParentPagingEntry->Pnle.Bits.Present = 1;
> -      }
> -
> -      ChildAttribute.Bits.Present = 0;
> -      ChildMask.Bits.Present      = 1;
> -    }
> -
>      if ((ParentPagingEntry->Pnle.Bits.ReadWrite == 0) && (Mask-
> >Bits.ReadWrite == 1) && (Attribute->Bits.ReadWrite == 1)) {
>        if (Modify) {
>          ParentPagingEntry->Pnle.Bits.ReadWrite = 1;
> --
> 2.31.1.windows.1