diff --git a/src/arch/i386/core/patch_cf.S b/src/arch/i386/core/patch_cf.S
new file mode 100644
index 00000000..97a62f49
--- /dev/null
+++ b/src/arch/i386/core/patch_cf.S
@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2009 H. Peter Anvin <hpa@zytor.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER )
+
+	.text
+	.arch i386
+	.code16
+
+/****************************************************************************
+ * Set/clear CF on the stack as appropriate, assumes stack is as it should
+ * be immediately before IRET
+ ****************************************************************************
+ */
+	.section ".text16", "ax", @progbits
+	.globl patch_cf
+patch_cf:
+	pushw	%bp
+	movw	%sp, %bp
+	setc	8(%bp)	/* Set/reset CF; clears PF, AF, ZF, SF */
+	popw	%bp
+	ret
+	.size patch_cf, . - patch_cf
diff --git a/src/arch/i386/firmware/pcbios/e820mangler.S b/src/arch/i386/firmware/pcbios/e820mangler.S
index 99ca519b..eeed51f8 100644
--- a/src/arch/i386/firmware/pcbios/e820mangler.S
+++ b/src/arch/i386/firmware/pcbios/e820mangler.S
@@ -492,18 +492,6 @@ get_mangled_e820:
 	ret
 	.size get_mangled_e820, . - get_mangled_e820
 
-/****************************************************************************
- * Set/clear CF on the stack as appropriate, assumes stack is as it should
- * be immediately before IRET
- ****************************************************************************
- */
-patch_cf:
-	pushw	%bp
-	movw	%sp, %bp
-	setc	8(%bp)	/* Set/reset CF; clears PF, AF, ZF, SF */
-	popw	%bp
-	ret
-
 /****************************************************************************
  * INT 15,e820 handler
  ****************************************************************************
diff --git a/src/arch/i386/interface/syslinux/comboot_call.c b/src/arch/i386/interface/syslinux/comboot_call.c
index e5bf11c9..b1489efd 100644
--- a/src/arch/i386/interface/syslinux/comboot_call.c
+++ b/src/arch/i386/interface/syslinux/comboot_call.c
@@ -669,6 +669,7 @@ void hook_comboot_interrupts ( ) {
 		              "pushw %%cs\n\t"
 		              "call prot_call\n\t"
 		              "addw $4, %%sp\n\t"
+			      "call patch_cf\n\t"
 		              "iret\n\t" )
 		          : : "i" ( int20 ) );
 
@@ -681,6 +682,7 @@ void hook_comboot_interrupts ( ) {
 		              "pushw %%cs\n\t"
 		              "call prot_call\n\t"
 		              "addw $4, %%sp\n\t"
+			      "call patch_cf\n\t"
 		              "iret\n\t" )
 		          : : "i" ( int21 ) );
 
@@ -693,6 +695,7 @@ void hook_comboot_interrupts ( ) {
 		              "pushw %%cs\n\t"
 		              "call prot_call\n\t"
 		              "addw $4, %%sp\n\t"
+			      "call patch_cf\n\t"
 		              "iret\n\t" )
 		          : : "i" ( int22) );