Commit Graph

50 Commits

Author SHA1 Message Date
Markus Armbruster
6f061ea10f fw_cfg: Split fw_cfg_keys.h off fw_cfg.h
Much of fw_cfg.h's contents is #ifndef NO_QEMU_PROTOS.  This lets a
few places include it without satisfying the dependencies of the
suppressed code.  If you somehow include it with NO_QEMU_PROTOS, any
future includes are ignored.  Unnecessarily unclean.

Move the stuff not under NO_QEMU_PROTOS into its own header
fw_cfg_keys.h, and include it as appropriate.  Tidy up the moved code
to please checkpatch.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:16 +01:00
Paolo Bonzini
269e235849 linuxboot: fix loading old kernels
Old kernels that used high memory only allowed the initrd to be in the
first 896MB of memory.  If you load the initrd above, they complain
that "initrd extends beyond end of memory".

In order to fix this, while not breaking machines with small amounts
of memory fixed by cdebec5 (linuxboot: compute initrd loading address,
2014-10-06), we need to distinguish two cases.  If pc.c placed the
initrd at end of memory, use the new algorithm based on the e801
memory map.  If instead pc.c placed the initrd at the maximum address
specified by the bzImage, leave it there.

The only interesting part is that the low-memory info block is now
loaded very early, in real mode, and thus the 32-bit address has
to be converted into a real mode segment.  The initrd address is
also patched in the info block before entering real mode, it is
simpler that way.

This fixes booting the RHEL4.8 32-bit installation image with 1GB
of RAM.

Cc: qemu-stable@nongnu.org
Cc: mst@redhat.com
Cc: jsnow@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-15 12:21:03 +01:00
Paolo Bonzini
cdebec5e40 linuxboot: compute initrd loading address
Even though hw/i386/pc.c tries to compute a valid loading address for the
initrd, close to the top of RAM, this does not take into account other
data that is malloced into that memory by SeaBIOS.

Luckily we can easily look at the memory map to find out how much memory is
used up there.  This patch places the initrd in the first four gigabytes,
below the first hole (as returned by INT 15h, AX=e801h).

Without this patch:
[    0.000000] init_memory_mapping: [mem 0x07000000-0x07fdffff]
[    0.000000] RAMDISK: [mem 0x0710a000-0x07fd7fff]

With this patch:
[    0.000000] init_memory_mapping: [mem 0x07000000-0x07fdffff]
[    0.000000] RAMDISK: [mem 0x07112000-0x07fdffff]

So linuxboot is able to use the 64k that were added as padding for
QEMU <= 2.1.

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-09 15:36:15 +02:00
Brad
46eef33b89 Fix QEMU build on OpenBSD on x86 archs
This resolves the build issue with building the ROMs on OpenBSD on x86 archs.
As of OpenBSD 5.3 the compiler builds PIE binaries by default and thus the
whole OS/packages and so forth. The ROMs need to have PIE disabled.
Check in configure whether the compiler supports the flags for disabling
PIE, and if it does then use them for building the ROMs. This fixes the
following buildbot failure:

>From the OpenBSD buildbots..
  Building optionrom/multiboot.img
ld: multiboot.o: relocation R_X86_64_16 can not be used when making a shared object; recompile with -fPIC

Signed-off by: Brad Smith <brad@comstyle.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-02-17 11:44:00 +00:00
Kevin Wolf
26a8ec0761 multiboot: Calculate upper_mem in the ROM
The upper_mem field of the Multiboot information struct doesn't really
contain the RAM size - 1 MB like we used to calculate it, but only the
memory from 1 MB up to the first (upper) memory hole.

In order to correctly retrieve this information, the multiboot ROM now
looks at the mmap it creates anyway and tries to find the size of
contiguous usable memory from 1 MB.

Drop the multiboot.c definition of lower_mem and upper_mem because both
are queried at runtime now.

Signed-off-by: Kevin Wolf <mail@kevin-wolf.de>
Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Message-id: 1372018066-21822-3-git-send-email-mail@kevin-wolf.de
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-06-28 14:01:52 -05:00
Kevin Wolf
390fb6b471 multiboot: Don't forget last mmap entry
When the BIOS returns ebx = 0, the current entry is still valid and
needs to be included in the Multiboot memory map.

Fixing this meant that using bx as the entry index doesn't work any
more because it's 0 on the last entry (and it was SeaBIOS-specific
anyway), so the whole loop had to change a bit and should be more
generic as a result (ebx can be an arbitrary continuation number now,
and the entry size returned by the BIOS is used instead of hard-coding
20 bytes).

Signed-off-by: Kevin Wolf <mail@kevin-wolf.de>
Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Message-id: 1372018066-21822-2-git-send-email-mail@kevin-wolf.de
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-06-28 14:01:52 -05:00
Paolo Bonzini
0d09e41a51 hw: move headers to include/
Many of these should be cleaned up with proper qdev-/QOM-ification.
Right now there are many catch-all headers in include/hw/ARCH depending
on cpu.h, and this makes it necessary to compile these files per-target.
However, fixing this does not belong in these patches.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-04-08 18:13:10 +02:00
Paolo Bonzini
c6e052f080 multiboot: fix e801 memory map
The e801 memory sizes in the multiboot structures hard-code the available
low memory to 640.  However, the value should not include the size of the
EBDA.  Fill the value in the option ROM, getting the size of low memory
from the BIOS.

Cc: Alexander Graf <agraf@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-11-30 08:27:47 -06:00
Jan Kiszka
0d6b9cc742 signrom: Rewrite as python script
Now that we have a hard dependency on python anyway, we can replace the
slow shell script to calculate the option ROM checksum with a fast AND
portable python version. Tested both with python 2.7 and 3.1.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
2012-04-16 15:41:20 +02:00
Jan Kiszka
501981126d kvmvapic: Use optionrom helpers
Use OPTION_ROM_START/END from the common header file, add comment to
init code.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-02-18 12:16:01 +02:00
Jan Kiszka
209ca750b9 optionsrom: Reserve space for checksum
Always add a byte before the final 512-bytes alignment to reserve the
space for the ROM checksum.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-02-18 12:16:00 +02:00
Jan Kiszka
1189aa519c kvmvapic: Simplify mp/up_set_tpr
The CH registers is only written, never read. So we can remove these
operations and, in case of up_set_tpr, also the ECX push/pop.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-02-18 12:16:00 +02:00
Jan Kiszka
2a2af967b0 kvmvapic: Add option ROM
This imports and builds the original VAPIC option ROM of qemu-kvm.
Its interaction with QEMU is described in the commit that introduces the
corresponding device model.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-02-18 12:15:57 +02:00
Jan Kiszka
6fbcef296a optionroms: Silence intermediate file removal
The build process of optionroms spits out an "rm ..." line. Moreover, it
removes all .o files that can be handy for debugging purposes. So
disable automatic intermediate removal.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-02-01 14:45:02 -06:00
Stefan Weil
e7d81004e4 Fix spelling in comments, documentation and messages
accidently->accidentally
annother->another
choosen->chosen
consideres->considers
decriptor->descriptor
developement->development
paramter->parameter
preceed->precede
preceeding->preceding
priviledge->privilege
propogation->propagation
substraction->subtraction
throught->through
upto->up to
usefull->useful

Fix also grammar in posix-aio-compat.c

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-12-14 11:09:44 +00:00
Gleb Natapov
75b9f69057 fix linuxboot.bin and multiboot.bin to not hijack int19
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>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-03-22 07:00:58 +01:00
Blue Swirl
4c3b5a4891 Add scripts directory
Move build and user scripts into scripts directory.

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-01-20 20:54:21 +00:00
Avi Kivity
33bbd1de5e optionrom: fix bugs in signrom.sh
signrom.sh has multiple bugs:

- the last byte is considered when calculating the existing checksum, but not
  when computing the correction
- apprently the 'expr' expression overflows and produces incorrect results with
  larger roms
- if the checksum happened to be zero, we calculated the correction byte to be
  256

Instead of rewriting this in half a line of python, this patch fixes the bugs.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-11-21 09:16:57 -06:00
Alexander Graf
590bf491a4 Fix multiboot compilation
Commit dd4239d657 broke multiboot. It replaced the
instruction "rep insb (%dx), %es:(%edi)" by the binary output of
"addr32 rep insb (%dx), %es:(%di)".

Linuxboot calls the respective helper function in a code16 section. So the
original instruction was automatically translated to its "addr32" equivalent.
For multiboot, we're running in code32 so gcc didn't add the "addr32" which
breaks the instruction.

This patch splits that helper function in one which uses addr32 and one which
does not, so everyone's happy.

The good news is that nobody probably cared so far. The bundled multiboot.bin
binary was built before the change and is thus correct.

Please also put this patch into -stable.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2010-06-09 12:35:18 +02:00
Avi Kivity
d0652aa8ac linuxboot: fix gdt address calculation
The gdt address calculation in linuxboot.bin is broken in two ways: first
it loads %cs into %eax, but that instruction leaves the high bits of %eax
undefined and we did not clear them.  Secondly, we completely ignore the
incorrect %eax, and use the undefined %ebx instead.

With these issues fixed, linuxboot works again.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-08 09:58:41 -06:00
Paolo Bonzini
076d247142 Use vpath directive
The vpath directive has two advantages over the VPATH variable:
1) it allows to skip searching of .o files; 2) the default semantics
are to append to the vpath, so there is no confusion between "VPATH=xyz"
and "VPATH+=xyz".

Since "vpath %.c %.h PATH" is not valid, I'm introducing a wrapper
macro to append one or more directories to the vpath.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-08 09:58:40 -06:00
Paolo Bonzini
36ecd7c016 Fix thinko in linuxboot.S
The %gs segment that was used was not matching the comments.
I just moved the GDT descriptor on the stack instead.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-12-18 11:26:26 -06:00
Adam Lackorzynski
53ea95de52 multiboot: Fix module loading and setting of mmap.
Signed-off-by: Adam Lackorzynski <adam@os.inf.tu-dresden.de>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-12-03 15:25:58 -06:00
Alexander Graf
dc61b0dc5a Make -kernel for linux work with bochsbios
While trying to run -kernel with -bios pc-bios/pcbios.bin, I realized
that I was actually writing data to %es, but only set up %ds to a 32-bit
segment we want to write to.

So at the end of the day the data hasn't actually been copied. Oops.

So here's a fix to set ES instead of DS, which makes -kernel work with
BOCHS bios again (and actually makes the code do the correct thing)!

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-12-03 15:25:58 -06:00
Juergen Lock
dd4239d657 Allow build of linuxboot.S with old assemblers
In the spirit of ff56954baf, fix the
build of linuxboot.S with old as(1) (as found in some BSD base systems)
by emitting the bytes of the insn it doesn't like instead.

Signed-off-by: Juergen Lock <nox@jelal.kn-bremen.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2009-11-21 09:32:23 +00:00
Alexander Graf
57a46d0579 Convert linux bootrom to external rom and fw_cfg
We already have a working multiboot implementation that uses fw_cfg to get
its kernel module etc. data in int19 runtime now.

So what's missing is a working linux boot option rom. While at it I figured it
would be a good idea to take the opcode generator out of pc.c and instead use
a proper option rom, like we do with multiboot.

So here it is - an fw_cfg using option rom for -kernel with linux!

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-11-17 10:39:03 -06:00
Alexander Graf
dd4b2659cd Move common option rom code to header file
We will have a linux boot option rom soon, so let's take all functionality
that might be useful for both to a header file that both roms can include.

That way we only have to write fw_cfg access code once.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-11-17 10:39:03 -06:00
Alexander Graf
77873196f3 Convert multiboot to fw_cfg backed data storage
Right now we load the guest kernel to RAM, fire off the BIOS, hope it
doesn't clobber memory and run an option rom that jumps into the kernel.

That breaks with SeaBIOS, as that clears memory. So let's read all
kernel, module etc. data using the fw_cfg interface when in the int19
handler.

This patch implements said mechanism for multiboot.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-11-17 10:39:02 -06:00
Juergen Lock
ff56954baf multiboot.S patch for old as(1) (was: Re: [Qemu-devel] Some OpenBSD/amd64 build fixes)
On Wed, Sep 23, 2009 at 10:55:02PM +0200, Juergen Lock wrote:
> On Wed, Sep 23, 2009 at 09:31:16PM +0100, Laurence Tratt wrote:
>[...]
> >  then the above error doesn't occur, but
> > pc-bios/optionrom/multiboot.S dies as follows:
> >
> >   $
> >     AS    optionrom/multiboot.o
> >   multiboot.S: Assembler messages:
> >   multiboot.S:116: Error: `%es:-4(%edi)' is not a valid 16 bit base/index
> > expression
> >   $
> >
> > What little Intel assembler I ever knew has long since departed from my
> > brain, so I don't know why that error occurs, nor what a fix might be.
> >
>  It occurs because of too old binutils (as(1) in this case), on FreeBSD
> we now have a port for newer ones,
> 	http://www.freshports.org/devel/binutils
> so I depend on that and have the optionrom Makefile use the new as
> like this: (the first change wrt CFLAGS is unrelated and has probably
> been fixed in the meantime; it caused gmake to complain about
> recursive use of CFLAGS.)
>
> Index: qemu/pc-bios/optionrom/Makefile
> @@ -9,10 +9,13 @@
>
>  CFLAGS = -Wall -Wstrict-prototypes -Werror -fomit-frame-pointer -fno-builtin
>  CFLAGS += -I$(SRC_PATH)
> -CFLAGS += $(call cc-option, $(CFLAGS), -fno-stack-protector,"")
> +CFLAGS := $(CFLAGS) $(call cc-option, $(CFLAGS), -fno-stack-protector,"")
>
>  build-all: multiboot.bin
>
> +%.o: %.S
> +	$(CC) -E $(CFLAGS) -o - -c $< |${LOCALBASE}/bin/as -V -Qy -o $@
> +
>  %.img: %.o
>  	$(call quiet-command,$(LD) -Ttext 0 -e _start -s -o $@ $<,"  Building $(TARGET_DIR)$@")
>

That patch didn't seem to help on OpenBSD so I now finally got around
making another one that just emits the bytes of the offending insn
instead so people can keep using old assemblers:

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-10-27 12:28:36 -05:00
Juan Quintela
4888ec2676 optionrom: create .PHONY variable
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-10-06 14:46:10 -05:00
Juan Quintela
3e4e4646ea optionrom: remove use of implicit RM variable
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-10-06 14:46:10 -05:00
Thomas Monjalon
fc3baad7bf restore CFLAGS check for conflict and fix recursive CFLAGS issue
cc-option uses more make-syntax to replace the shell "if/else".

Issue with recursive += is fixed by doing the first assignment
simply-expanded, as explained in
http://www.gnu.org/software/make/manual/html_node/Appending.html

Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-10-05 09:32:53 -05:00
Juan Quintela
ae20c622ec optionrom: make clean should remove raw and .d
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-09-09 17:31:26 -05:00
Juan Quintela
9b083b62e3 otionrom: Use local CFLAGS no global one
It is needed by %.o : %.c rule.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-09-09 17:31:26 -05:00
Juan Quintela
8a2e6ab501 Remove CFLAGS parameter in cc-option
With cc-option we are testing if gcc just accept a particular option, we don't need CFLAGS at all.  And this fixes the recursive problem with CFLAGS

Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-09-09 17:31:24 -05:00
Juan Quintela
a558ee1776 Rename CPPFLAGS to QEMU_CFLAGS
Now we have to variables: QEMU_CFLAGS: flags without which we can't compile
CFLAGS: "-g -O2"

We can now run:

make CFLAGS="-fbar" foo.o
make CFLAGS="" foo.o
make CFLAGS="-O3" foo.o

And it all should work.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Message-Id:
2009-08-10 13:05:39 -05:00
Alexander Graf
c66b57fc14 Fix checksum writing in signboot.sh
The printf command takes an octal value after \, so we have to convert
our decimal representation to octal first and then write it.

This unbreaks extboot signing. Multiboot wasn't affected yet because
the checksum was < 8.

Spotted and first patch by Glauber Costa <glommer@redhat.com>.
Printf idea by Paolo Bonzini <bonzini@gnu.org>.

Signed-off-by: Alexander Graf <agraf@suse.de>
CC: Glauber Costa <glommer@redhat.com>
CC: Paolo Bonzini <bonzini@gnu.org>
CC: Jan Ondrej <ondrejj@salstar.sk>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Message-Id:
2009-08-10 13:05:30 -05:00
malc
0ff6697d1c Do not try to invoke shebang scripts directly (NFS issues)
Signed-off-by: malc <av1474@comtv.ru>
2009-08-10 03:41:46 +04:00
Paul Brook
c05ac895cb Option rom makefile fixes
Fix toplevel option rom makefile rules.

Signed-off-by: Paul Brook <paul@codesourcery.com>
2009-07-31 13:19:39 +01:00
Blue Swirl
925ce05f81 Fix out of tree build broken by 791e08c753
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2009-07-27 19:59:36 +00:00
Juan Quintela
3c87f43bd4 use cc-option for optionrom
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-07-27 14:10:55 -05:00
Juan Quintela
791e08c753 Use quiet-command for building optionrom
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-07-27 14:10:55 -05:00
Christoph Egger
99772ae208 signrom.sh: portability fix
Attached patch makes signrom.sh working on NetBSD.
The output of the 'od' command leads to a syntax error
which breaks the build.

Signed-off-by: Christoph Egger <Christoph.Egger@amd.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-07-22 10:58:49 -05:00
Blue Swirl
8167ee8839 Update to a hopefully more future proof FSF address
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2009-07-16 20:47:01 +00:00
Anthony Liguori
24d904eab3 Don't copy multiboot.bin into pc-bios after built
That dirties the working directory of the tree.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-07-16 08:28:14 -05:00
Anthony Liguori
7aa486fe6b Fix multiboot.bin build on mingw32
This combination of ld/object was suggested by Bartlomiej Celary

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-07-16 08:28:14 -05:00
Alexander Graf
89e671e3f3 Replace signrom with shell script v3
In order to not execute code we just compiled, let's replace signrom
with a shell script that does the same thing while staying compatible
to pretty much every system available.

This should make cross-compilation for windows easier.

aliguori: fix build when objdir != srcdir

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-07-09 16:06:38 -05:00
Blue Swirl
8676188b75 Work around Solaris gas problem
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2009-07-03 19:25:29 +00:00
Alexander Graf
253d0942fa Multiboot build system v4
In order to build the multiboot option rom, we need a Makefile and a tool
to sign the rom with.

Both are provided by this patch and mostly taken from the extboot source,
written by Anthony Liguori.

Once built, the resulting binary gets copied to pc-bios automatically.

Building also occurs automatically when on an x86 host.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-06-29 14:17:49 -05:00
Alexander Graf
f16408dfb0 Multiboot support v5
This patch implements support for Multiboot on x86 for -kernel.
Multiboot is a "new" approach to get rid of different bootloaders, providing
a unified interface for the kernel. It supports command line options and
kernel modules.

The two probably best known projects using multiboot are Xen and GNU Hurd.

This implementation should be mostly feature-complete. It is missing VBE
extensions, but as no system uses them currently it does not really hurt.

To use multiboot, specify the kernel as -kernel option. Modules should be given
as -initrd options, seperated by a comma (,). -append also works.

Please bear in mind that grub also does gzip decompression, which qemu does
not do yet. To run existing images, please ungzip them first.

The guest multiboot loader code is implemented as option rom using int 19.
Parts of the work are based on efforts by Rene Rebe, who originally ported
my code to int 19.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-06-29 13:52:12 -05:00