From: Gleb Natapov <gleb@redhat.com>
To: qemu-devel@nongnu.org
Subject: [Qemu-devel] [PATCH] fix linuxboot.bin and multiboot.bin to not hijack int19
Date: Mon, 31 Jan 2011 11:02:47 +0200 [thread overview]
Message-ID: <20110131090247.GT14750@redhat.com> (raw)
Currently linuxboot.bin and multiboot.bin option roms override int19
vector to intercept boot process. No sane option rom should do that.
Provide bev entry instead that will be called by BIOS if option rom
is selected for booting.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
---
Note that this patch should be applied after qemu will upgrade to Seabios
that supports boot order. Otherwise there will be change in behavior
since option rom will not be selected for booting by default.
diff --git a/pc-bios/optionrom/linuxboot.S b/pc-bios/optionrom/linuxboot.S
index c109363..79b3ae8 100644
--- a/pc-bios/optionrom/linuxboot.S
+++ b/pc-bios/optionrom/linuxboot.S
@@ -22,6 +22,8 @@
#include "optionrom.h"
+#define PRODUCT "Linux loader"
+
BOOT_ROM_START
run_linuxboot:
diff --git a/pc-bios/optionrom/multiboot.S b/pc-bios/optionrom/multiboot.S
index 9131837..069c4e8 100644
--- a/pc-bios/optionrom/multiboot.S
+++ b/pc-bios/optionrom/multiboot.S
@@ -20,6 +20,8 @@
#include "optionrom.h"
+#define PRODUCT "multiboot loader"
+
#define MULTIBOOT_MAGIC 0x2badb002
#define GS_PROT_JUMP 0
diff --git a/pc-bios/optionrom/optionrom.h b/pc-bios/optionrom/optionrom.h
index fbdd48a..95dbdda 100644
--- a/pc-bios/optionrom/optionrom.h
+++ b/pc-bios/optionrom/optionrom.h
@@ -93,31 +93,41 @@
.global _start; \
_start:; \
.short 0xaa55; \
- .byte (_end - _start) / 512;
+ .byte (_end - _start) / 512; \
+ lret; \
+ .org 0x18; \
+ .short 0; \
+ .short _pnph; \
+ _pnph: \
+ .ascii "$PnP"; \
+ .byte 0x01; \
+ .byte ( _pnph_len / 16 ); \
+ .short 0x0000; \
+ .byte 0x00; \
+ .byte 0x00; \
+ .long 0x00000000; \
+ .short _manufacturer; \
+ .short _product; \
+ .long 0x00000000; \
+ .short 0x0000; \
+ .short 0x0000; \
+ .short _bev; \
+ .short 0x0000; \
+ .short 0x0000; \
+ .equ _pnph_len, . - _pnph;
#define BOOT_ROM_START \
OPTION_ROM_START \
- push %eax; \
- push %ds; \
- \
- /* setup ds so we can access the IVT */ \
- xor %ax, %ax; \
- mov %ax, %ds; \
- \
- /* install our int 19 handler */ \
- movw $int19_handler, (0x19*4); \
- mov %cs, (0x19*4+2); \
- \
- pop %ds; \
- pop %eax; \
- lret; \
- \
- int19_handler:; \
+ _bev:; \
/* DS = CS */ \
movw %cs, %ax; \
movw %ax, %ds;
#define OPTION_ROM_END \
+ _manufacturer:; \
+ .asciz "QEMU"; \
+ _product:; \
+ .asciz PRODUCT; \
.align 512, 0; \
_end:
--
Gleb.
next reply other threads:[~2011-01-31 9:11 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-01-31 9:02 Gleb Natapov [this message]
2011-01-31 11:41 ` [Qemu-devel] [PATCH] fix linuxboot.bin and multiboot.bin to not hijack int19 Alexander Graf
2011-01-31 11:50 ` Gleb Natapov
2011-01-31 11:53 ` Alexander Graf
2011-02-01 23:02 ` Anthony Liguori
2011-02-02 5:06 ` Gleb Natapov
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