From: Anthony Liguori <anthony@codemonkey.ws>
To: Gleb Natapov <gleb@redhat.com>
Cc: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] [PATCH] fix linuxboot.bin and multiboot.bin to not hijack int19
Date: Tue, 01 Feb 2011 17:02:55 -0600 [thread overview]
Message-ID: <4D48911F.2060802@codemonkey.ws> (raw)
In-Reply-To: <20110131090247.GT14750@redhat.com>
On 01/31/2011 03:02 AM, Gleb Natapov wrote:
> 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.
>
I don't think there's a SeaBIOS release yet that includes the boot order
support.
Regards,
Anthony Liguori
> 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 prev parent reply other threads:[~2011-02-01 23:03 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-01-31 9:02 [Qemu-devel] [PATCH] fix linuxboot.bin and multiboot.bin to not hijack int19 Gleb Natapov
2011-01-31 11:41 ` Alexander Graf
2011-01-31 11:50 ` Gleb Natapov
2011-01-31 11:53 ` Alexander Graf
2011-02-01 23:02 ` Anthony Liguori [this message]
2011-02-02 5:06 ` Gleb Natapov
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