From 3964c936cbc12bb481de26da7bf360e188add773 Mon Sep 17 00:00:00 2001
From: Daniel Victor <ilauncherdeveloper@gmail.com>
Date: Fri, 7 Nov 2025 18:51:13 -0300
Subject: [PATCH] [FREELDR] Add the relocator caller on realmode code (#8439)

CORE-19882
---
 boot/freeldr/freeldr/arch/realmode/amd64.S | 16 ++++++++++------
 boot/freeldr/freeldr/arch/realmode/i386.S  | 16 +++++++++++++---
 2 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/boot/freeldr/freeldr/arch/realmode/amd64.S b/boot/freeldr/freeldr/arch/realmode/amd64.S
index b1e88af37d6..1e8f172be97 100644
--- a/boot/freeldr/freeldr/arch/realmode/amd64.S
+++ b/boot/freeldr/freeldr/arch/realmode/amd64.S
@@ -29,15 +29,18 @@ Startup:
     mov byte ptr ds:[BSS_BootPartition], dh
 
     /* Setup a real mode stack */
-    mov sp, word ptr ds:[stack16]
+    mov sp, STACK16ADDR
+
+    /* Enable A20 address line */
+    call EnableA20
+
+    /* Relocate FreeLdr if necessary */
+    call RelocateFreeLdr
 
     /* Output first status */
     mov si, offset Msg_Starting
     call writestr
 
-    /* Enable A20 address line */
-    call EnableA20
-
     /* Check the CPU */
     call CheckFor64BitSupport
     test al, al
@@ -361,12 +364,13 @@ CallbackTable:
     .word PnpBiosGetDeviceNode
     .word PnpBiosGetDockStationInformation
 
-    /* 16-bit stack pointer */
+    /* 16-bit stack pointer (the code must change it to the current stack pointer later) */
 stack16:
-    .word STACK16ADDR
+    .word 0
 
 
 #include "int386.inc"
+#include "relocator.inc"
 #include "helpers.inc"
 #include "pxe.inc"
 #include "pnp.inc"
diff --git a/boot/freeldr/freeldr/arch/realmode/i386.S b/boot/freeldr/freeldr/arch/realmode/i386.S
index 2accf63ce52..41c9ad65f4b 100644
--- a/boot/freeldr/freeldr/arch/realmode/i386.S
+++ b/boot/freeldr/freeldr/arch/realmode/i386.S
@@ -25,11 +25,18 @@ RealModeEntryPoint:
     mov ss, ax
 
     /* Setup the stack */
-    mov sp, word ptr ds:[stack16]
+    mov sp, STACK16ADDR
 
     /* Enable A20 address line */
     call EnableA20
 
+    /* Relocate FreeLdr if necessary */
+    call RelocateFreeLdr
+
+    /* Output first status */
+    mov si, offset Msg_Starting
+    call writestr
+
     /* Save real mode entry point in shared memory */
     mov dword ptr ds:[BSS_RealModeEntry], offset switch_to_real16
 
@@ -54,6 +61,8 @@ RealModeEntryPoint:
 
     jmp exit_to_protected
 
+Msg_Starting:
+    .ascii "Starting FreeLoader...", CR, LF, NUL
 
 /* This is the entry point from protected mode */
 switch_to_real16:
@@ -143,9 +152,9 @@ CallbackTable:
     .word PnpBiosGetDockStationInformation
 
 
-    /* 16-bit stack pointer */
+    /* 16-bit stack pointer (the code must change it to the current stack pointer later) */
 stack16:
-    .word    STACK16ADDR
+    .word 0
 
 
 .align 4    /* force 4-byte alignment */
@@ -191,6 +200,7 @@ rmode_idtptr:
     .long 0             /* Base Address */
 
 #include "int386.inc"
+#include "relocator.inc"
 #if defined(SARCH_PC98)
 #include "helpers_pc98.inc"
 #else