[Qemu-devel] [PATCH] multiboot: Fix module loading and setting of mmap

[Adam Lackorzynski <adam@os.inf.tu-dresden.de>]

Hi,

I need to following to fix multiboot booting for me.

Should linuxboot.bin and multiboot.bin end up in pc-bios instead of
pc-bios/optionrom?


Signed-off-by: Adam Lackorzynski <adam@os.inf.tu-dresden.de>
---
 hw/pc.c                       |    4 ++--
 pc-bios/optionrom/multiboot.S |    5 ++++-
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/hw/pc.c b/hw/pc.c
index 7c791c4..1c8f95c 100644
--- a/hw/pc.c
+++ b/hw/pc.c
@@ -661,7 +661,7 @@ static int load_multiboot(void *fw_cfg,
 
             /* append module data at the end of last module */
             mb_kernel_data = qemu_realloc(mb_kernel_data,
-                                          mh_load_addr - mb_mod_end);
+                                          mb_mod_end - mh_load_addr);
             load_image(initrd_filename,
                        mb_kernel_data + mb_mod_start - mh_load_addr);
 
@@ -720,7 +720,7 @@ static int load_multiboot(void *fw_cfg,
     fw_cfg_add_bytes(fw_cfg, FW_CFG_INITRD_DATA, mb_bootinfo_data,
                      sizeof(bootinfo));
 
-    option_rom[nb_option_roms] = "multiboot.bin";
+    option_rom[nb_option_roms] = "optionrom/multiboot.bin";
     nb_option_roms++;
 
     return 1; /* yes, we are multiboot */
diff --git a/pc-bios/optionrom/multiboot.S b/pc-bios/optionrom/multiboot.S
index be5c9fc..9131837 100644
--- a/pc-bios/optionrom/multiboot.S
+++ b/pc-bios/optionrom/multiboot.S
@@ -62,6 +62,9 @@ run_multiboot:
 	add		%eax, %ebx
 	movl		%ebx, %gs:GS_GDT_DESC + 2
 
+	xor		%eax, %eax
+	mov		%eax, %es
+
 	/* Read the bootinfo struct into RAM */
 	read_fw_blob(FW_CFG_INITRD)
 
@@ -71,7 +74,7 @@ run_multiboot:
 	mov		%ax, %fs
 
 	/* ES = mmap_addr */
-	mov		%eax, %fs:0x48
+	mov 		%fs:48, %eax
 	shr		$4, %eax
 	mov		%ax, %es
 
-- 
1.6.5.2

Adam
-- 
Adam                 adam@os.inf.tu-dresden.de
  Lackorzynski         http://os.inf.tu-dresden.de/~adam/