Re: [edk2-devel] [PATCH 1/6] UefiCpuPkg/CpuPageTableLib: Remove unneeded 'if' condition

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

Sorry for adding wrong reviewers. Will resend the patch set.
 
Thanks,
Dun

-----Original Message-----
From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of duntan
Sent: Friday, March 3, 2023 5:55 PM
To: devel@edk2.groups.io
Cc: Bi, Dandan <dandan.bi@intel.com>; Gao, Liming <gaoliming@byosoft.com.cn>; Ni, Ray <ray.ni@intel.com>
Subject: [edk2-devel] [PATCH 1/6] 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 check for (ParentPagingEntry->Pnle.Bits.Present == 0) won't is always FALSE.

Signed-off-by: Dun Tan <dun.tan@intel.com>
Cc: Dandan Bi <dandan.bi@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Ray Ni <ray.ni@intel.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