[comboot] Unhook interrupt vectors after returning from a COMBOOT image

diff --git a/src/arch/i386/image/com32.c b/src/arch/i386/image/com32.c
index 3e81f48..00f7526 100644 (file)
--- a/src/arch/i386/image/com32.c
+++ b/src/arch/i386/image/com32.c
@@ -136,6 +136,7 @@ static int com32_exec ( struct image *image ) {
                break;
        }
 
+       unhook_comboot_interrupts();
        comboot_force_text_mode();
 
        return 0;

diff --git a/src/arch/i386/image/comboot.c b/src/arch/i386/image/comboot.c
index e045264..d9b16c5 100644 (file)
--- a/src/arch/i386/image/comboot.c
+++ b/src/arch/i386/image/comboot.c
@@ -205,6 +205,7 @@ static int comboot_exec ( struct image *image ) {
                break;
        }
 
+       unhook_comboot_interrupts();
        comboot_force_text_mode();
 
        return 0;

diff --git a/src/arch/i386/include/comboot.h b/src/arch/i386/include/comboot.h
index 4376650..6b8ea6b 100644 (file)
--- a/src/arch/i386/include/comboot.h
+++ b/src/arch/i386/include/comboot.h
@@ -64,6 +64,7 @@ typedef struct {
 } comboot_shuffle_descriptor;
 
 extern void hook_comboot_interrupts ( );
+extern void unhook_comboot_interrupts ( );
 
 /* These are not the correct prototypes, but it doens't matter, 
  * as we only ever get the address of these functions;

diff --git a/src/arch/i386/interface/syslinux/comboot_call.c b/src/arch/i386/interface/syslinux/comboot_call.c
index f37aa2a..c641c84 100644 (file)
--- a/src/arch/i386/interface/syslinux/comboot_call.c
+++ b/src/arch/i386/interface/syslinux/comboot_call.c
@@ -616,3 +616,18 @@ void hook_comboot_interrupts ( ) {
        hook_bios_interrupt ( 0x22, ( unsigned int ) int22_wrapper,
                              &int22_vector );
 }
+
+/**
+ * Unhook BIOS interrupts related to COMBOOT API (INT 20h, 21h, 22h)
+ */
+void unhook_comboot_interrupts ( ) {
+
+       unhook_bios_interrupt ( 0x20, ( unsigned int ) int20_wrapper,
+                               &int20_vector );
+
+       unhook_bios_interrupt ( 0x21, ( unsigned int ) int21_wrapper,
+                               &int21_vector );
+
+       unhook_bios_interrupt ( 0x22, ( unsigned int ) int22_wrapper,
+                               &int22_vector );
+}