diff --git a/src/arch/i386/include/biosint.h b/src/arch/i386/include/biosint.h
index d4e34963..d365cf01 100644
--- a/src/arch/i386/include/biosint.h
+++ b/src/arch/i386/include/biosint.h
@@ -6,9 +6,22 @@
  *
  */
 
+#include <realmode.h>
+
 struct segoff;
 
-extern int hooked_bios_interrupts;
+/**
+ * Hooked interrupt count
+ *
+ * At exit, after unhooking all possible interrupts, this counter
+ * should be examined.  If it is non-zero, it means that we failed to
+ * unhook at least one interrupt vector, and so must not free up the
+ * memory we are using.  (Note that this also implies that we should
+ * re-hook INT 15 in order to hide ourselves from the memory map).
+ */
+extern uint16_t __text16 ( hooked_bios_interrupts );
+#define hooked_bios_interrupts __use_text16 ( hooked_bios_interrupts )
+
 extern void hook_bios_interrupt ( unsigned int interrupt, unsigned int handler,
 				  struct segoff *chain_vector );
 extern int unhook_bios_interrupt ( unsigned int interrupt,
diff --git a/src/arch/i386/interface/pcbios/biosint.c b/src/arch/i386/interface/pcbios/biosint.c
index 8ef2d7ab..1306f918 100644
--- a/src/arch/i386/interface/pcbios/biosint.c
+++ b/src/arch/i386/interface/pcbios/biosint.c
@@ -7,17 +7,6 @@
  *
  */
 
-/**
- * Hooked interrupt count
- *
- * At exit, after unhooking all possible interrupts, this counter
- * should be examined.  If it is non-zero, it means that we failed to
- * unhook at least one interrupt vector, and so must not free up the
- * memory we are using.  (Note that this also implies that we should
- * re-hook INT 15 in order to hide ourselves from the memory map).
- */
-int hooked_bios_interrupts = 0;
-
 /**
  * Hook INT vector
  *
diff --git a/src/arch/i386/prefix/dskprefix.S b/src/arch/i386/prefix/dskprefix.S
index e3a39cce..0156812a 100644
--- a/src/arch/i386/prefix/dskprefix.S
+++ b/src/arch/i386/prefix/dskprefix.S
@@ -353,6 +353,7 @@ msg1end:
 	.word 0xAA55
 
 start_runtime:
+	/* Install gPXE */
 	call	install
 
 	/* Set up real-mode stack */
@@ -368,7 +369,10 @@ start_runtime:
 	pushl	$main
 	pushw	%cs
 	call	prot_call
-	popl	%eax /* discard */
+	popl	%ecx /* discard */
+
+	/* Uninstall gPXE */
+	call	uninstall
 
 	/* Boot next device */
 	int $0x18
diff --git a/src/arch/i386/prefix/hdprefix.S b/src/arch/i386/prefix/hdprefix.S
index ffe1ee57..086d7f45 100644
--- a/src/arch/i386/prefix/hdprefix.S
+++ b/src/arch/i386/prefix/hdprefix.S
@@ -82,6 +82,7 @@ load_failed:
 	.byte 0x55, 0xaa
 
 start_image:
+	/* Install gPXE */
 	call	install
 
 	/* Set up real-mode stack */
@@ -97,7 +98,10 @@ start_image:
 	pushl	$main
 	pushw	%cs
 	call	prot_call
-	popl	%eax /* discard */
+	popl	%ecx /* discard */
+
+	/* Uninstall gPXE */
+	call	uninstall
 
 	/* Boot next device */
 	int $0x18
diff --git a/src/arch/i386/prefix/libprefix.S b/src/arch/i386/prefix/libprefix.S
index 61549618..56ca64d9 100644
--- a/src/arch/i386/prefix/libprefix.S
+++ b/src/arch/i386/prefix/libprefix.S
@@ -537,17 +537,20 @@ install_block:
 	.code16
 	.globl	alloc_basemem
 alloc_basemem:
+	/* Preserve registers */
+	pushw	%fs
+
 	/* FBMS => %ax as segment address */
-	movw	$0x40, %ax
-	movw	%ax, %fs
+	pushw	$0x40
+	popw	%fs
 	movw	%fs:0x13, %ax
 	shlw	$6, %ax
 
-	/* .data16 segment address */
+	/* Calculate .data16 segment address */
 	subw	$_data16_memsz_pgh, %ax
 	pushw	%ax
 
-	/* .text16 segment address */
+	/* Calculate .text16 segment address */
 	subw	$_text16_memsz_pgh, %ax
 	pushw	%ax
 
@@ -555,12 +558,67 @@ alloc_basemem:
 	shrw	$6, %ax
 	movw	%ax, %fs:0x13
 
-	/* Return */
+	/* Retrieve .text16 and .data16 segment addresses */
 	popw	%ax
 	popw	%bx
+
+	/* Restore registers and return */
+	popw	%fs
 	ret
 	.size alloc_basemem, . - alloc_basemem
 
+/****************************************************************************
+ * free_basemem (real-mode near call)
+ *
+ * Free space allocated with alloc_basemem.
+ *
+ * Parameters:
+ *   %ax : .text16 segment address
+ *   %bx : .data16 segment address
+ * Returns:
+ *   %ax : 0 if successfully freed
+ * Corrupts:
+ *   none
+ ****************************************************************************
+ */
+	.section ".text16"
+	.code16
+	.globl	free_basemem
+free_basemem:
+	/* Preserve registers */
+	pushw	%fs
+
+	/* Check FBMS counter */
+	pushw	%ax
+	shrw	$6, %ax
+	pushw	$0x40
+	popw	%fs
+	cmpw	%ax, %fs:0x13
+	popw	%ax
+	jne	1f
+
+	/* Check hooked interrupt count */
+	cmpw	$0, %cs:hooked_bios_interrupts
+	jne	1f
+
+	/* OK to free memory */
+	addw	$_text16_memsz_pgh, %ax
+	addw	$_data16_memsz_pgh, %ax
+	shrw	$6, %ax
+	movw	%ax, %fs:0x13
+	xorw	%ax, %ax
+
+1:	/* Restore registers and return */
+	popw	%fs
+	ret
+	.size free_basemem, . - free_basemem
+
+	.section ".text16.data"
+	.globl	hooked_bios_interrupts
+hooked_bios_interrupts:
+	.word	0
+	.size	hooked_bios_interrupts, . - hooked_bios_interrupts
+
 /****************************************************************************
  * install (real-mode near call)
  *
@@ -709,6 +767,29 @@ prot_call_vector:
 	.size prot_call_vector, . - prot_call_vector
 #endif
 
+/****************************************************************************
+ * uninstall (real-mode near call)
+ *
+ * Uninstall all text and data segments.
+ *
+ * Parameters:
+ *   %ax  : .text16 segment address
+ *   %bx  : .data16 segment address
+ * Returns:
+ *   none
+ * Corrupts:
+ *   none
+ ****************************************************************************
+ */
+	.section ".text16"
+	.code16
+	.globl uninstall
+uninstall:
+	call	free_basemem
+	ret
+	.size uninstall, . - uninstall
+
+
 
 	/* File split information for the compressor */
 #if COMPRESS
diff --git a/src/arch/i386/prefix/lkrnprefix.S b/src/arch/i386/prefix/lkrnprefix.S
index f23e4076..094263d2 100644
--- a/src/arch/i386/prefix/lkrnprefix.S
+++ b/src/arch/i386/prefix/lkrnprefix.S
@@ -189,6 +189,7 @@ run_gpxe:
 	movw	%ax, %ss
 	movw	$0x7c00, %sp
 
+	/* Install gPXE */
 	call	install
 
 	/* Set up real-mode stack */
@@ -204,7 +205,10 @@ run_gpxe:
 	pushl	$main
 	pushw	%cs
 	call	prot_call
-	popl	%eax /* discard */
+	popl	%ecx /* discard */
+
+	/* Uninstall gPXE */
+	call	uninstall
 
 	/* Boot next device */
 	int $0x18
diff --git a/src/arch/i386/prefix/nbiprefix.S b/src/arch/i386/prefix/nbiprefix.S
index ec210094..d1753e30 100644
--- a/src/arch/i386/prefix/nbiprefix.S
+++ b/src/arch/i386/prefix/nbiprefix.S
@@ -52,7 +52,7 @@ memlen:	.long	_filesz - 512
  *****************************************************************************
  */
 entry:
-	/* Install low and high memory regions */
+	/* Install gPXE */
 	call	install
 
 	/* Jump to .text16 segment */
@@ -64,7 +64,10 @@ entry:
 	pushl	$main
 	pushw	%cs
 	call	prot_call
-	popl	%eax /* discard */
+	popl	%ecx /* discard */
+
+	/* Uninstall gPXE */
+	call	uninstall
 
 	/* Reboot system */
 	int $0x19
diff --git a/src/arch/i386/prefix/pxeprefix.S b/src/arch/i386/prefix/pxeprefix.S
index 32ff2961..d1eb962f 100644
--- a/src/arch/i386/prefix/pxeprefix.S
+++ b/src/arch/i386/prefix/pxeprefix.S
@@ -318,7 +318,7 @@ print_free_basemem:
  *****************************************************************************
  */	
 finished:
-	jmp	run_etherboot
+	jmp	run_gpxe
 
 /*****************************************************************************
  * Subroutine: print segment:offset address
@@ -554,11 +554,11 @@ flags:			.word UNDI_FL_STARTED
 	.equ undi_device_size, ( . - undi_device )
 
 /*****************************************************************************
- * Run Etherboot main code
+ * Run gPXE main code
  *****************************************************************************
  */	
-run_etherboot:
-	/* Install Etherboot */
+run_gpxe:
+	/* Install gPXE */
 	call	install
 
 	/* Set up real-mode stack */
@@ -585,7 +585,10 @@ run_etherboot:
 	pushl	$main
 	pushw	%cs
 	call	prot_call
-	popl	%eax /* discard */
+	popl	%ecx /* discard */
+
+	/* Uninstall gPXE */
+	call	uninstall
 
 	/* Boot next device */
 	int	$0x18
diff --git a/src/arch/i386/prefix/romprefix.S b/src/arch/i386/prefix/romprefix.S
index 7b545f4b..a6431cd9 100644
--- a/src/arch/i386/prefix/romprefix.S
+++ b/src/arch/i386/prefix/romprefix.S
@@ -591,8 +591,11 @@ exec:	/* Set %ds = %cs */
 	pushl	$main
 	pushw	%cs
 	call	prot_call
-	/* No need to clean up stack; we are about to reload %ss:sp */
-	
+	popl	%ecx /* discard */
+
+	/* Uninstall gPXE */
+	call	uninstall
+
 	/* Restore BIOS stack */
 	movw	%dx, %ss
 	movw	%bp, %sp