From c476450456c964cd78ad0af4171e8687eea7dc90 Mon Sep 17 00:00:00 2001
From: Fu Siyuan <siyuan.fu@intel.com>
Date: Fri, 16 Oct 2015 07:18:51 +0000
Subject: [PATCH] NetworkPkg: reset DHCP child when leaving PXE LoadFile.

The DHCP4 can have only one configured child instance so we need to reset
the DHCP4 child when leaving PXE driver's LoadFile() function, otherwise the
other programs which also need to use DHCP4 (like HTTP boot) will be impacted.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Fu Siyuan <siyuan.fu@intel.com>
Reviewed-by: Ye Ting <ting.ye@intel.com>
Reviewed-by: Sriram Subramanian <sriram-s@hpe.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18616 6f19259b-4bc3-4df7-8a09-765794883524
---
 NetworkPkg/UefiPxeBcDxe/PxeBcImpl.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/NetworkPkg/UefiPxeBcDxe/PxeBcImpl.c b/NetworkPkg/UefiPxeBcDxe/PxeBcImpl.c
index 367a1356ab..12e5566a79 100644
--- a/NetworkPkg/UefiPxeBcDxe/PxeBcImpl.c
+++ b/NetworkPkg/UefiPxeBcDxe/PxeBcImpl.c
@@ -2392,6 +2392,16 @@ EfiPxeLoadFile (
     //   3. unsupported.
     //
     PxeBc->Stop (PxeBc);
+  } else {
+    //
+    // The DHCP4 can have only one configured child instance so we need to stop
+    // reset the DHCP4 child before we return. Otherwise these programs which 
+    // also need to use DHCP4 will be impacted.
+    //
+    if (!PxeBc->Mode->UsingIpv6) {
+      Private->Dhcp4->Stop (Private->Dhcp4);
+      Private->Dhcp4->Configure (Private->Dhcp4, NULL);
+    }
   }
 
   return Status;