From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Vladimir 'phcoder' Serbinenko" <phcoder@gmail.com>
Subject: Re: [GRUB2 PATCH v3 4/4] multiboot2: Add support for
	relocatable images
Date: Thu, 10 Mar 2016 21:41:26 +0100
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To: Daniel Kiper <daniel.kiper@oracle.com>
Cc: "jgross@suse.com" <jgross@suse.com>, "grub-devel@gnu.org" <grub-devel@gnu.org>, "eric.snowberg@oracle.com" <eric.snowberg@oracle.com>, "arvidjaar@gmail.com" <arvidjaar@gmail.com>, "andrew.cooper3@citrix.com" <andrew.cooper3@citrix.com>, "cardoe@cardoe.com" <cardoe@cardoe.com>, "pgnet.dev@gmail.com" <pgnet.dev@gmail.com>, "roy.franz@linaro.org" <roy.franz@linaro.org>, "ning.sun@intel.com" <ning.sun@intel.com>, "david.vrabel@citrix.com" <david.vrabel@citrix.com>, "jbeulich@suse.com" <jbeulich@suse.com>, "stefano.stabellini@eu.citrix.com" <stefano.stabellini@eu.citrix.com>, "xen-devel@lists.xenproject.org" <xen-devel@lists.xenproject.org>, "qiaowei.ren@intel.com" <qiaowei.ren@intel.com>, "richard.l.maliszewski@intel.com" <richard.l.maliszewski@intel.com>, "gang.wei@intel.com" <gang.wei@intel.com>, "fu.wei@linaro.org" <fu.wei@linaro.org>, "seth.goldberg@oracle.com" <seth>
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On Wednesday, March 2, 2016, Daniel Kiper <daniel.kiper@oracle.com> wrote:

> Currently multiboot2 protocol loads image exactly at address specified in
> ELF or multiboot2 header. This solution works quite well on legacy BIOS
> platforms. It is possible because memory regions are placed at predictable
> addresses (though I was not able to find any spec which says that it is
> strong requirement, so, it looks that it is just a goodwill of hardware
> designers). However, EFI platforms are more volatile. Even if required
> memory regions live at specific addresses then they are sometimes simply
> not free (e.g. used by boot/runtime services on Dell PowerEdge R820 and
> OVMF). This means that you are not able to simply set up final image
> destination on build time. You have to provide method to relocate image
> contents to real load address which is usually different than load address
> specified in ELF and multiboot2 headers.
>
> This patch provides all needed machinery to do self relocation in image
> code.
> First of all GRUB2 reads min_addr (min. load addr), max_addr (max. load
> addr),
> align (required image alignment), preference (it says which memory regions
> are
> preferred by image, e.g. none, low, high) from
> multiboot_header_tag_relocatable
> header tag contained in binary. Later loader tries to fulfill request (not
> only
> that one) and if it succeeds then it informs image about real load address
> via
> multiboot_tag_base_addr tag. At this stage GRUB2 role is finished. Starting
> from now executable must cope with relocations itself using whole static
> and dynamic knowledge provided by boot loader.
>
> This patch does not provide functionality which could do relocations using
> ELF relocation data. However, I was asked by Konrad Rzeszutek Wilk and
> Vladimir
> 'phcoder' Serbinenko to investigate that thing. It looks that relevant
> machinery
> could be added to existing code (including this patch) without huge effort.
> Additionally, ELF relocation could live in parallel with self relocation
> provided
> by this patch. However, during research I realized that first of all we
> should
> establish the details how ELF relocatable image should look like and how
> it should
> be build. At least to build proper test/example files.
>
> As I saw multiboot2 protocol is able to consume ET_EXEC and ET_DYN ELF
> files.
> Potentially we can use ET_DYN file type. It can be build with gcc/ld -pie
> option.
> However, it contains a lot of unneeded stuff (e.g. INTERP, DYNAMIC,
> GNU_EH_FRAME
> program headers) and it could be quite difficult to drop them (Hmmm... Is
> it
> possible to build it properly with custom ld script?).

How big are they? Are they a real problem?

> So, I have checked ET_EXEC
> file type. Sadly in this case linker by default resolves all local symbol
> relocations
> and removes relocation related sections. Fortunately it is possible to
> leave them
> as is with simple -q/--emit-relocs ld option. However, output file is
> quite fragile
> and any operation on it should be done with great care (e.g. strip should
> be called
> with --strip-unneeded option). So, this solution is not perfect too. It
> means that
> maybe we should look for better solution. However, I think that we should
> not use
> any custom tools and focus on functionalities provided by compiler and
> binutils.
> In this context ld scripts looks quite promising but maybe you have better
> solutions.
> So, what do you think about that?
>
 Another possibility is to use intermediary .o files like we do for modules
and like Linux does for modules AFAIR.

>
> This patch was tested with Xen image which uses that functionality.
> However, this Xen
> feature is still under development and new patchset will be released in
> about 3-4 weeks.
>
> Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com <javascript:;>>
> ---
> v3 - suggestions/fixes:
>    - reduce number of casts
>      (suggested by Konrad Rzeszutek Wilk),
>    - remove unneeded space at the end of line
>      (suggested by Konrad Rzeszutek Wilk),
>    - improve commit message
>      (suggested by Konrad Rzeszutek Wilk).
> ---
>  grub-core/loader/i386/multiboot_mbi.c |    6 ++-
>  grub-core/loader/multiboot.c          |   12 ++++--
>  grub-core/loader/multiboot_elfxx.c    |   28 ++++++++++----
>  grub-core/loader/multiboot_mbi2.c     |   65
> ++++++++++++++++++++++++++++++---
>  include/grub/multiboot.h              |    4 +-
>  include/multiboot2.h                  |   24 ++++++++++++
>  6 files changed, 120 insertions(+), 19 deletions(-)
>
> diff --git a/grub-core/loader/i386/multiboot_mbi.c
> b/grub-core/loader/i386/multiboot_mbi.c
> index f60b702..4fc83ed 100644
> --- a/grub-core/loader/i386/multiboot_mbi.c
> +++ b/grub-core/loader/i386/multiboot_mbi.c
> @@ -72,7 +72,8 @@ load_kernel (grub_file_t file, const char *filename,
>    grub_err_t err;
>    if (grub_multiboot_quirks & GRUB_MULTIBOOT_QUIRK_BAD_KLUDGE)
>      {
> -      err = grub_multiboot_load_elf (file, filename, buffer);
> +      err = grub_multiboot_load_elf (file, filename, buffer, 0, 0, 0, 0,
> +                                    GRUB_RELOCATOR_PREFERENCE_NONE, NULL,
> 0);
>        if (err == GRUB_ERR_NONE) {
>         return GRUB_ERR_NONE;
>        }
> @@ -121,7 +122,8 @@ load_kernel (grub_file_t file, const char *filename,
>        return GRUB_ERR_NONE;
>      }
>
> -  return grub_multiboot_load_elf (file, filename, buffer);
> +  return grub_multiboot_load_elf (file, filename, buffer, 0, 0, 0, 0,
> +                                 GRUB_RELOCATOR_PREFERENCE_NONE, NULL, 0);
>  }
>
>  static struct multiboot_header *
> diff --git a/grub-core/loader/multiboot.c b/grub-core/loader/multiboot.c
> index 18038fd..c0f51b6 100644
> --- a/grub-core/loader/multiboot.c
> +++ b/grub-core/loader/multiboot.c
> @@ -208,12 +208,18 @@ static grub_uint64_t highest_load;
>  /* Load ELF32 or ELF64.  */
>  grub_err_t
>  grub_multiboot_load_elf (grub_file_t file, const char *filename,
> -                        void *buffer)
> +                        void *buffer, int relocatable, grub_uint32_t
> min_addr,
> +                        grub_uint32_t max_addr, grub_size_t align,
> grub_uint32_t preference,
> +                        grub_uint32_t *base_addr, int
> avoid_efi_boot_services)
>  {
>    if (grub_multiboot_is_elf32 (buffer))
> -    return grub_multiboot_load_elf32 (file, filename, buffer);
> +    return grub_multiboot_load_elf32 (file, filename, buffer, relocatable,
> +                                     min_addr, max_addr, align,
> preference,
> +                                     base_addr, avoid_efi_boot_services);
>    else if (grub_multiboot_is_elf64 (buffer))
> -    return grub_multiboot_load_elf64 (file, filename, buffer);
> +    return grub_multiboot_load_elf64 (file, filename, buffer, relocatable,
> +                                     min_addr, max_addr, align,
> preference,
> +                                     base_addr, avoid_efi_boot_services);
>
>    return grub_error (GRUB_ERR_UNKNOWN_OS, N_("invalid arch-dependent ELF
> magic"));
>  }
> diff --git a/grub-core/loader/multiboot_elfxx.c
> b/grub-core/loader/multiboot_elfxx.c
> index e3a39b6..0c01569 100644
> --- a/grub-core/loader/multiboot_elfxx.c
> +++ b/grub-core/loader/multiboot_elfxx.c
> @@ -51,7 +51,10 @@ CONCAT(grub_multiboot_is_elf, XX) (void *buffer)
>  }
>
>  static grub_err_t
> -CONCAT(grub_multiboot_load_elf, XX) (grub_file_t file, const char
> *filename, void *buffer)
> +CONCAT(grub_multiboot_load_elf, XX) (grub_file_t file, const char
> *filename,
> +                                    void *buffer, int relocatable,
> grub_uint32_t min_addr,
> +                                    grub_uint32_t max_addr, grub_size_t
> align, grub_uint32_t preference,
> +                                    grub_uint32_t *base_addr, int
> avoid_efi_boot_services)
>  {
>    Elf_Ehdr *ehdr = (Elf_Ehdr *) buffer;
>    char *phdr_base;
> @@ -89,19 +92,30 @@ CONCAT(grub_multiboot_load_elf, XX) (grub_file_t file,
> const char *filename, voi
>           if (phdr(i)->p_paddr + phdr(i)->p_memsz > highest_load)
>             highest_load = phdr(i)->p_paddr + phdr(i)->p_memsz;
>
> -         grub_dprintf ("multiboot_loader", "segment %d: paddr=0x%lx,
> memsz=0x%lx, vaddr=0x%lx\n",
> -                       i, (long) phdr(i)->p_paddr, (long)
> phdr(i)->p_memsz, (long) phdr(i)->p_vaddr);
> +         grub_dprintf ("multiboot_loader", "segment %d: paddr=0x%lx,
> memsz=0x%lx, vaddr=0x%lx,"
> +                       "align=0x%lx, relocatable=%d,
> avoid_efi_boot_services=%d\n", i,
> +                       (long) phdr(i)->p_paddr, (long) phdr(i)->p_memsz,
> (long) phdr(i)->p_vaddr,
> +                       (long) align, relocatable,
> avoid_efi_boot_services);
>
>           {
>             grub_relocator_chunk_t ch;
> -           err = grub_relocator_alloc_chunk_addr
> (grub_multiboot_relocator,
> -                                                  &ch, phdr(i)->p_paddr,
> -                                                  phdr(i)->p_memsz);
> +
> +           if (relocatable)
> +             err = grub_relocator_alloc_chunk_align
> (grub_multiboot_relocator, &ch,
> +                                                     min_addr, max_addr -
> phdr(i)->p_memsz,
> +                                                     phdr(i)->p_memsz,
> align ? align : 1,
> +                                                     preference,
> avoid_efi_boot_services);
> +           else
> +             err = grub_relocator_alloc_chunk_addr
> (grub_multiboot_relocator,
> +                                                    &ch, phdr(i)->p_paddr,
> +                                                    phdr(i)->p_memsz);
>             if (err)
>               {
>                 grub_dprintf ("multiboot_loader", "Error loading phdr
> %d\n", i);
>                 return err;
>               }
> +           if (base_addr)
> +             *base_addr = get_physical_target_address (ch);
>             source = get_virtual_current_address (ch);
>           }
>
> @@ -208,7 +222,7 @@ CONCAT(grub_multiboot_load_elf, XX) (grub_file_t file,
> const char *filename, voi
>                                                     + 1, sh->sh_size,
>                                                     sh->sh_addralign,
>
> GRUB_RELOCATOR_PREFERENCE_NONE,
> -                                                   0);
> +
>  avoid_efi_boot_services);
>             if (err)
>               {
>                 grub_dprintf ("multiboot_loader", "Error loading shdr
> %d\n", i);
> diff --git a/grub-core/loader/multiboot_mbi2.c
> b/grub-core/loader/multiboot_mbi2.c
> index ce68f48..03725a1 100644
> --- a/grub-core/loader/multiboot_mbi2.c
> +++ b/grub-core/loader/multiboot_mbi2.c
> @@ -68,6 +68,7 @@ static grub_size_t elf_sec_num, elf_sec_entsize;
>  static unsigned elf_sec_shstrndx;
>  static void *elf_sections;
>  static int keep_bs = 0;
> +static grub_uint32_t base_addr = 0;
>
>  void
>  grub_multiboot_add_elfsyms (grub_size_t num, grub_size_t entsize,
> @@ -107,11 +108,14 @@ grub_multiboot_load (grub_file_t file, const char
> *filename)
>    grub_err_t err;
>    struct multiboot_header_tag *tag;
>    struct multiboot_header_tag_address *addr_tag = NULL;
> -  int entry_specified = 0, efi_entry_specified = 0;
> +  struct multiboot_header_tag_relocatable *rel_tag;
> +  int entry_specified = 0, efi_entry_specified = 0, relocatable = 0;
>    grub_addr_t entry = 0, efi_entry = 0;
> -  grub_uint32_t console_required = 0;
> +  grub_uint32_t console_required = 0, min_addr = 0;
> +  grub_uint32_t max_addr = 0, preference = GRUB_RELOCATOR_PREFERENCE_NONE;
>    struct multiboot_header_tag_framebuffer *fbtag = NULL;
>    int accepted_consoles = GRUB_MULTIBOOT_CONSOLE_EGA_TEXT;
> +  grub_size_t align = 0;
>
>    buffer = grub_malloc (MULTIBOOT_SEARCH);
>    if (!buffer)
> @@ -174,6 +178,7 @@ grub_multiboot_load (grub_file_t file, const char
> *filename)
>               case MULTIBOOT_TAG_TYPE_EFI_BS:
>               case MULTIBOOT_TAG_TYPE_EFI32_IH:
>               case MULTIBOOT_TAG_TYPE_EFI64_IH:
> +             case MULTIBOOT_TAG_TYPE_BASE_ADDR:
>                 break;
>
>               default:
> @@ -215,6 +220,27 @@ grub_multiboot_load (grub_file_t file, const char
> *filename)
>         accepted_consoles |= GRUB_MULTIBOOT_CONSOLE_FRAMEBUFFER;
>         break;
>
> +      case MULTIBOOT_HEADER_TAG_RELOCATABLE:
> +       relocatable = 1;
> +       rel_tag = (struct multiboot_header_tag_relocatable *) tag;
> +       min_addr = rel_tag->min_addr;
> +       max_addr = rel_tag->max_addr;
> +       align = rel_tag->align;
> +       switch (rel_tag->preference)
> +         {
> +         case MULTIBOOT_LOAD_PREFERENCE_LOW:
> +           preference = GRUB_RELOCATOR_PREFERENCE_LOW;
> +           break;
> +
> +         case MULTIBOOT_LOAD_PREFERENCE_HIGH:
> +           preference = GRUB_RELOCATOR_PREFERENCE_HIGH;
> +           break;
> +
> +         default:
> +           preference = GRUB_RELOCATOR_PREFERENCE_NONE;
> +         }
> +       break;
> +
>         /* GRUB always page-aligns modules.  */
>        case MULTIBOOT_HEADER_TAG_MODULE_ALIGN:
>         break;
> @@ -260,15 +286,22 @@ grub_multiboot_load (grub_file_t file, const char
> *filename)
>        else
>         code_size = load_size;
>
> -      err = grub_relocator_alloc_chunk_addr (grub_multiboot_relocator,
> -                                            &ch, load_addr,
> -                                            code_size);
> +      if (relocatable)
> +       err = grub_relocator_alloc_chunk_align (grub_multiboot_relocator,
> &ch,
> +                                               min_addr, max_addr -
> code_size,
> +                                               code_size, align ? align :
> 1,
> +                                               preference, keep_bs);
> +      else
> +       err = grub_relocator_alloc_chunk_addr (grub_multiboot_relocator,
> +                                              &ch, load_addr,
> +                                              code_size);
>        if (err)
>         {
>           grub_dprintf ("multiboot_loader", "Error loading aout kludge\n");
>           grub_free (buffer);
>           return err;
>         }
> +      base_addr = get_physical_target_address (ch);
>        source = get_virtual_current_address (ch);
>
>        if ((grub_file_seek (file, offset)) == (grub_off_t) -1)
> @@ -290,7 +323,9 @@ grub_multiboot_load (grub_file_t file, const char
> *filename)
>      }
>    else
>      {
> -      err = grub_multiboot_load_elf (file, filename, buffer);
> +      err = grub_multiboot_load_elf (file, filename, buffer,
> +                                    relocatable, min_addr, max_addr,
> +                                    align, preference, &base_addr,
> keep_bs);
>        if (err)
>         {
>           grub_free (buffer);
> @@ -303,6 +338,14 @@ grub_multiboot_load (grub_file_t file, const char
> *filename)
>    else if (entry_specified)
>      grub_multiboot_payload_eip = entry;
>
> +  if (relocatable)
> +    {
> +      if (base_addr > min_addr)
> +       grub_multiboot_payload_eip += base_addr - min_addr;
> +      else
> +       grub_multiboot_payload_eip -= min_addr - base_addr;
> +    }
> +
>
Why is it relative to min_addr? Sounds like it should be just an offset
from base addr. What do ET_DYN files use?

>    if (fbtag)
>      err = grub_multiboot_set_console (GRUB_MULTIBOOT_CONSOLE_FRAMEBUFFER,
>                                       accepted_consoles,
> @@ -409,6 +452,7 @@ grub_multiboot_get_mbi_size (void)
>                  + grub_get_multiboot_mmap_count ()
>                  * sizeof (struct multiboot_mmap_entry)),
> MULTIBOOT_TAG_ALIGN)
>      + ALIGN_UP (sizeof (struct multiboot_tag_framebuffer),
> MULTIBOOT_TAG_ALIGN)
> +    + ALIGN_UP (sizeof (struct multiboot_tag_base_addr),
> MULTIBOOT_TAG_ALIGN)
>  #ifdef GRUB_MACHINE_EFI
>  #ifdef __i386__
>      + ALIGN_UP (sizeof (struct multiboot_tag_efi32), MULTIBOOT_TAG_ALIGN)
> @@ -698,6 +742,15 @@ grub_multiboot_make_mbi (grub_uint32_t *target)
>    ptrorig += (2 * sizeof (grub_uint32_t)) / sizeof
> (grub_properly_aligned_t);
>
>    {
> +    struct multiboot_tag_base_addr *tag = (struct multiboot_tag_base_addr
> *) ptrorig;
> +    tag->type = MULTIBOOT_TAG_TYPE_BASE_ADDR;
> +    tag->size = sizeof (struct multiboot_tag_base_addr);
> +    tag->base_addr = base_addr;
> +    ptrorig += ALIGN_UP (tag->size, MULTIBOOT_TAG_ALIGN)
> +       / sizeof (grub_properly_aligned_t);
> +  }
> +
> +  {
>      struct multiboot_tag_string *tag = (struct multiboot_tag_string *)
> ptrorig;
>      tag->type = MULTIBOOT_TAG_TYPE_CMDLINE;
>      tag->size = sizeof (struct multiboot_tag_string) + cmdline_size;
> diff --git a/include/grub/multiboot.h b/include/grub/multiboot.h
> index e13c084..ec322b0 100644
> --- a/include/grub/multiboot.h
> +++ b/include/grub/multiboot.h
> @@ -94,7 +94,9 @@ grub_multiboot_load (grub_file_t file, const char
> *filename);
>  /* Load ELF32 or ELF64.  */
>  grub_err_t
>  grub_multiboot_load_elf (grub_file_t file, const char *filename,
> -                        void *buffer);
> +                        void *buffer, int relocatable, grub_uint32_t
> min_addr,
> +                        grub_uint32_t max_addr, grub_size_t align,
> grub_uint32_t preference,
> +                        grub_uint32_t *base_addr, int
> avoid_efi_boot_services);
>  extern grub_size_t grub_multiboot_pure_size;
>  extern grub_size_t grub_multiboot_alloc_mbi;
>  extern grub_uint32_t grub_multiboot_payload_eip;
> diff --git a/include/multiboot2.h b/include/multiboot2.h
> index 36a174f..c09bdbc 100644
> --- a/include/multiboot2.h
> +++ b/include/multiboot2.h
> @@ -62,6 +62,7 @@
>  #define MULTIBOOT_TAG_TYPE_EFI_BS            18
>  #define MULTIBOOT_TAG_TYPE_EFI32_IH          19
>  #define MULTIBOOT_TAG_TYPE_EFI64_IH          20
> +#define MULTIBOOT_TAG_TYPE_BASE_ADDR         21
>
>  #define MULTIBOOT_HEADER_TAG_END  0
>  #define MULTIBOOT_HEADER_TAG_INFORMATION_REQUEST  1
> @@ -72,11 +73,16 @@
>  #define MULTIBOOT_HEADER_TAG_MODULE_ALIGN  6
>  #define MULTIBOOT_HEADER_TAG_EFI_BS  7
>  #define MULTIBOOT_HEADER_TAG_ENTRY_ADDRESS_EFI64  9
> +#define MULTIBOOT_HEADER_TAG_RELOCATABLE  10
>
>  #define MULTIBOOT_ARCHITECTURE_I386  0
>  #define MULTIBOOT_ARCHITECTURE_MIPS32  4
>  #define MULTIBOOT_HEADER_TAG_OPTIONAL 1
>
> +#define MULTIBOOT_LOAD_PREFERENCE_NONE 0
> +#define MULTIBOOT_LOAD_PREFERENCE_LOW 1
> +#define MULTIBOOT_LOAD_PREFERENCE_HIGH 2
> +
>  #define MULTIBOOT_CONSOLE_FLAGS_CONSOLE_REQUIRED 1
>  #define MULTIBOOT_CONSOLE_FLAGS_EGA_TEXT_SUPPORTED 2
>
> @@ -161,6 +167,17 @@ struct multiboot_header_tag_module_align
>    multiboot_uint32_t size;
>  };
>
> +struct multiboot_header_tag_relocatable
> +{
> +  multiboot_uint16_t type;
> +  multiboot_uint16_t flags;
> +  multiboot_uint32_t size;
> +  multiboot_uint32_t min_addr;
> +  multiboot_uint32_t max_addr;
> +  multiboot_uint32_t align;
> +  multiboot_uint32_t preference;
> +};
> +
>  struct multiboot_color
>  {
>    multiboot_uint8_t red;
> @@ -387,6 +404,13 @@ struct multiboot_tag_efi64_ih
>    multiboot_uint64_t pointer;
>  };
>
> +struct multiboot_tag_base_addr
> +{
> +  multiboot_uint32_t type;
> +  multiboot_uint32_t size;
> +  multiboot_uint32_t base_addr;
> +};
> +
>  #endif /* ! ASM_FILE */
>
>  #endif /* ! MULTIBOOT_HEADER */
> --
> 1.7.10.4
>
>

-- 
Regards
Vladimir 'phcoder' Serbinenko

--001a1147cd9ca4f527052db7d6d5
Content-Type: text/html; charset=UTF-8
Content-Transfer-Encoding: quoted-printable

<br><br>On Wednesday, March 2, 2016, Daniel Kiper &lt;<a href=3D"mailto:dan=
iel.kiper@oracle.com">daniel.kiper@oracle.com</a>&gt; wrote:<br><blockquote=
 class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc soli=
d;padding-left:1ex">Currently multiboot2 protocol loads image exactly at ad=
dress specified in<br>
ELF or multiboot2 header. This solution works quite well on legacy BIOS<br>
platforms. It is possible because memory regions are placed at predictable<=
br>
addresses (though I was not able to find any spec which says that it is<br>
strong requirement, so, it looks that it is just a goodwill of hardware<br>
designers). However, EFI platforms are more volatile. Even if required<br>
memory regions live at specific addresses then they are sometimes simply<br=
>
not free (e.g. used by boot/runtime services on Dell PowerEdge R820 and<br>
OVMF). This means that you are not able to simply set up final image<br>
destination on build time. You have to provide method to relocate image<br>
contents to real load address which is usually different than load address<=
br>
specified in ELF and multiboot2 headers.<br>
<br>
This patch provides all needed machinery to do self relocation in image cod=
e.<br>
First of all GRUB2 reads min_addr (min. load addr), max_addr (max. load add=
r),<br>
align (required image alignment), preference (it says which memory regions =
are<br>
preferred by image, e.g. none, low, high) from multiboot_header_tag_relocat=
able<br>
header tag contained in binary. Later loader tries to fulfill request (not =
only<br>
that one) and if it succeeds then it informs image about real load address =
via<br>
multiboot_tag_base_addr tag. At this stage GRUB2 role is finished. Starting=
<br>
from now executable must cope with relocations itself using whole static<br=
>
and dynamic knowledge provided by boot loader.<br>
<br>
This patch does not provide functionality which could do relocations using<=
br>
ELF relocation data. However, I was asked by Konrad Rzeszutek Wilk and Vlad=
imir<br>
&#39;phcoder&#39; Serbinenko to investigate that thing. It looks that relev=
ant machinery<br>
could be added to existing code (including this patch) without huge effort.=
<br>
Additionally, ELF relocation could live in parallel with self relocation pr=
ovided<br>
by this patch. However, during research I realized that first of all we sho=
uld<br>
establish the details how ELF relocatable image should look like and how it=
 should<br>
be build. At least to build proper test/example files.<br>
<br>
As I saw multiboot2 protocol is able to consume ET_EXEC and ET_DYN ELF file=
s.<br>
Potentially we can use ET_DYN file type. It can be build with gcc/ld -pie o=
ption.<br>
However, it contains a lot of unneeded stuff (e.g. INTERP, DYNAMIC, GNU_EH_=
FRAME<br>
program headers) and it could be quite difficult to drop them (Hmmm... Is i=
t<br>
possible to build it properly with custom ld script?).</blockquote><div>How=
 big are they? Are they a real problem?=C2=A0</div><blockquote class=3D"gma=
il_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-lef=
t:1ex"> So, I have checked ET_EXEC<br>
file type. Sadly in this case linker by default resolves all local symbol r=
elocations<br>
and removes relocation related sections. Fortunately it is possible to leav=
e them<br>
as is with simple -q/--emit-relocs ld option. However, output file is quite=
 fragile<br>
and any operation on it should be done with great care (e.g. strip should b=
e called<br>
with --strip-unneeded option). So, this solution is not perfect too. It mea=
ns that<br>
maybe we should look for better solution. However, I think that we should n=
ot use<br>
any custom tools and focus on functionalities provided by compiler and binu=
tils.<br>
In this context ld scripts looks quite promising but maybe you have better =
solutions.<br>
So, what do you think about that?<br></blockquote><div>=C2=A0Another possib=
ility is to use intermediary .o files like we do for modules and like Linux=
 does for modules AFAIR.</div><blockquote class=3D"gmail_quote" style=3D"ma=
rgin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<br>
This patch was tested with Xen image which uses that functionality. However=
, this Xen<br>
feature is still under development and new patchset will be released in abo=
ut 3-4 weeks.<br>
<br>
Signed-off-by: Daniel Kiper &lt;<a href=3D"javascript:;" onclick=3D"_e(even=
t, &#39;cvml&#39;, &#39;daniel.kiper@oracle.com&#39;)">daniel.kiper@oracle.=
com</a>&gt;<br>
---<br>
v3 - suggestions/fixes:<br>
=C2=A0 =C2=A0- reduce number of casts<br>
=C2=A0 =C2=A0 =C2=A0(suggested by Konrad Rzeszutek Wilk),<br>
=C2=A0 =C2=A0- remove unneeded space at the end of line<br>
=C2=A0 =C2=A0 =C2=A0(suggested by Konrad Rzeszutek Wilk),<br>
=C2=A0 =C2=A0- improve commit message<br>
=C2=A0 =C2=A0 =C2=A0(suggested by Konrad Rzeszutek Wilk).<br>
---<br>
=C2=A0grub-core/loader/i386/multiboot_mbi.c |=C2=A0 =C2=A0 6 ++-<br>
=C2=A0grub-core/loader/multiboot.c=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 |=C2=
=A0 =C2=A012 ++++--<br>
=C2=A0grub-core/loader/multiboot_elfxx.c=C2=A0 =C2=A0 |=C2=A0 =C2=A028 ++++=
++++++----<br>
=C2=A0grub-core/loader/multiboot_mbi2.c=C2=A0 =C2=A0 =C2=A0|=C2=A0 =C2=A065=
 ++++++++++++++++++++++++++++++---<br>
=C2=A0include/grub/multiboot.h=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 |=C2=A0 =C2=A0 4 +-<br>
=C2=A0include/multiboot2.h=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 |=C2=A0 =C2=A024 ++++++++++++<br>
=C2=A06 files changed, 120 insertions(+), 19 deletions(-)<br>
<br>
diff --git a/grub-core/loader/i386/multiboot_mbi.c b/grub-core/loader/i386/=
multiboot_mbi.c<br>
index f60b702..4fc83ed 100644<br>
--- a/grub-core/loader/i386/multiboot_mbi.c<br>
+++ b/grub-core/loader/i386/multiboot_mbi.c<br>
@@ -72,7 +72,8 @@ load_kernel (grub_file_t file, const char *filename,<br>
=C2=A0 =C2=A0grub_err_t err;<br>
=C2=A0 =C2=A0if (grub_multiboot_quirks &amp; GRUB_MULTIBOOT_QUIRK_BAD_KLUDG=
E)<br>
=C2=A0 =C2=A0 =C2=A0{<br>
-=C2=A0 =C2=A0 =C2=A0 err =3D grub_multiboot_load_elf (file, filename, buff=
er);<br>
+=C2=A0 =C2=A0 =C2=A0 err =3D grub_multiboot_load_elf (file, filename, buff=
er, 0, 0, 0, 0,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 GRUB_RELOCATOR_PREFERE=
NCE_NONE, NULL, 0);<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0if (err =3D=3D GRUB_ERR_NONE) {<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 return GRUB_ERR_NONE;<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0}<br>
@@ -121,7 +122,8 @@ load_kernel (grub_file_t file, const char *filename,<br=
>
=C2=A0 =C2=A0 =C2=A0 =C2=A0return GRUB_ERR_NONE;<br>
=C2=A0 =C2=A0 =C2=A0}<br>
<br>
-=C2=A0 return grub_multiboot_load_elf (file, filename, buffer);<br>
+=C2=A0 return grub_multiboot_load_elf (file, filename, buffer, 0, 0, 0, 0,=
<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0GRUB_RELOCATOR_PREFERENCE_NONE=
, NULL, 0);<br>
=C2=A0}<br>
<br>
=C2=A0static struct multiboot_header *<br>
diff --git a/grub-core/loader/multiboot.c b/grub-core/loader/multiboot.c<br=
>
index 18038fd..c0f51b6 100644<br>
--- a/grub-core/loader/multiboot.c<br>
+++ b/grub-core/loader/multiboot.c<br>
@@ -208,12 +208,18 @@ static grub_uint64_t highest_load;<br>
=C2=A0/* Load ELF32 or ELF64.=C2=A0 */<br>
=C2=A0grub_err_t<br>
=C2=A0grub_multiboot_load_elf (grub_file_t file, const char *filename,<br>
-=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 void *buffer)<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 void *buffer, int relocatable, grub_uint32_t min_addr,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 grub_uint32_t max_addr, grub_size_t align, grub_uint32_t prefere=
nce,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 grub_uint32_t *base_addr, int avoid_efi_boot_services)<br>
=C2=A0{<br>
=C2=A0 =C2=A0if (grub_multiboot_is_elf32 (buffer))<br>
-=C2=A0 =C2=A0 return grub_multiboot_load_elf32 (file, filename, buffer);<b=
r>
+=C2=A0 =C2=A0 return grub_multiboot_load_elf32 (file, filename, buffer, re=
locatable,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0min_addr, max_ad=
dr, align, preference,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0base_addr, avoid=
_efi_boot_services);<br>
=C2=A0 =C2=A0else if (grub_multiboot_is_elf64 (buffer))<br>
-=C2=A0 =C2=A0 return grub_multiboot_load_elf64 (file, filename, buffer);<b=
r>
+=C2=A0 =C2=A0 return grub_multiboot_load_elf64 (file, filename, buffer, re=
locatable,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0min_addr, max_ad=
dr, align, preference,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0base_addr, avoid=
_efi_boot_services);<br>
<br>
=C2=A0 =C2=A0return grub_error (GRUB_ERR_UNKNOWN_OS, N_(&quot;invalid arch-=
dependent ELF magic&quot;));<br>
=C2=A0}<br>
diff --git a/grub-core/loader/multiboot_elfxx.c b/grub-core/loader/multiboo=
t_elfxx.c<br>
index e3a39b6..0c01569 100644<br>
--- a/grub-core/loader/multiboot_elfxx.c<br>
+++ b/grub-core/loader/multiboot_elfxx.c<br>
@@ -51,7 +51,10 @@ CONCAT(grub_multiboot_is_elf, XX) (void *buffer)<br>
=C2=A0}<br>
<br>
=C2=A0static grub_err_t<br>
-CONCAT(grub_multiboot_load_elf, XX) (grub_file_t file, const char *filenam=
e, void *buffer)<br>
+CONCAT(grub_multiboot_load_elf, XX) (grub_file_t file, const char *filenam=
e,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 void *buffer, int relo=
catable, grub_uint32_t min_addr,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 grub_uint32_t max_addr=
, grub_size_t align, grub_uint32_t preference,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 grub_uint32_t *base_ad=
dr, int avoid_efi_boot_services)<br>
=C2=A0{<br>
=C2=A0 =C2=A0Elf_Ehdr *ehdr =3D (Elf_Ehdr *) buffer;<br>
=C2=A0 =C2=A0char *phdr_base;<br>
@@ -89,19 +92,30 @@ CONCAT(grub_multiboot_load_elf, XX) (grub_file_t file, =
const char *filename, voi<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 if (phdr(i)-&gt;p_paddr + phdr(i)-&gt;p_=
memsz &gt; highest_load)<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 highest_load =3D phdr(i)-&gt;p_pa=
ddr + phdr(i)-&gt;p_memsz;<br>
<br>
-=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0grub_dprintf (&quot;multiboot_loader&quo=
t;, &quot;segment %d: paddr=3D0x%lx, memsz=3D0x%lx, vaddr=3D0x%lx\n&quot;,<=
br>
-=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0i, (long) phdr(i)-&gt;p_paddr, (long) phdr(i)-&gt;p_memsz, (long)=
 phdr(i)-&gt;p_vaddr);<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0grub_dprintf (&quot;multiboot_loader&quo=
t;, &quot;segment %d: paddr=3D0x%lx, memsz=3D0x%lx, vaddr=3D0x%lx,&quot;<br=
>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0&quot;align=3D0x%lx, relocatable=3D%d, avoid_efi_boot_services=3D=
%d\n&quot;, i,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0(long) phdr(i)-&gt;p_paddr, (long) phdr(i)-&gt;p_memsz, (long) ph=
dr(i)-&gt;p_vaddr,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0(long) align, relocatable, avoid_efi_boot_services);<br>
<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 {<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 grub_relocator_chunk_t ch;<br>
-=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0err =3D grub_relocator_alloc_chun=
k_addr (grub_multiboot_relocator,<br>
-=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 &amp;ch, phdr(i)-&gt;p_paddr,<br>
-=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 phdr(i)-&gt;p_memsz);<br>
+<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0if (relocatable)<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0err =3D grub_relocator_all=
oc_chunk_align (grub_multiboot_relocator, &amp;ch,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0min_addr, max_addr - phdr(i)-&gt;p=
_memsz,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0phdr(i)-&gt;p_memsz, align ? align=
 : 1,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0preference, avoid_efi_boot_service=
s);<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0else<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0err =3D grub_relocator_all=
oc_chunk_addr (grub_multiboot_relocator,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 &amp;ch, phdr(i)-&gt;p_paddr,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 phdr(i)-&gt;p_memsz);<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 if (err)<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 {<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 grub_dprintf (&quot=
;multiboot_loader&quot;, &quot;Error loading phdr %d\n&quot;, i);<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 return err;<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 }<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0if (base_addr)<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0*base_addr =3D get_physica=
l_target_address (ch);<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 source =3D get_virtual_current_ad=
dress (ch);<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 }<br>
<br>
@@ -208,7 +222,7 @@ CONCAT(grub_multiboot_load_elf, XX) (grub_file_t file, =
const char *filename, voi<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 + 1, sh-&gt;sh_size,<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 sh-&gt;sh_addralign,<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 GRUB_RELOCATOR_PREFERENCE_NONE,<br>
-=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A00);<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0avoid_efi_boot_services);<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 if (err)<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 {<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 grub_dprintf (&quot=
;multiboot_loader&quot;, &quot;Error loading shdr %d\n&quot;, i);<br>
diff --git a/grub-core/loader/multiboot_mbi2.c b/grub-core/loader/multiboot=
_mbi2.c<br>
index ce68f48..03725a1 100644<br>
--- a/grub-core/loader/multiboot_mbi2.c<br>
+++ b/grub-core/loader/multiboot_mbi2.c<br>
@@ -68,6 +68,7 @@ static grub_size_t elf_sec_num, elf_sec_entsize;<br>
=C2=A0static unsigned elf_sec_shstrndx;<br>
=C2=A0static void *elf_sections;<br>
=C2=A0static int keep_bs =3D 0;<br>
+static grub_uint32_t base_addr =3D 0;<br>
<br>
=C2=A0void<br>
=C2=A0grub_multiboot_add_elfsyms (grub_size_t num, grub_size_t entsize,<br>
@@ -107,11 +108,14 @@ grub_multiboot_load (grub_file_t file, const char *fi=
lename)<br>
=C2=A0 =C2=A0grub_err_t err;<br>
=C2=A0 =C2=A0struct multiboot_header_tag *tag;<br>
=C2=A0 =C2=A0struct multiboot_header_tag_address *addr_tag =3D NULL;<br>
-=C2=A0 int entry_specified =3D 0, efi_entry_specified =3D 0;<br>
+=C2=A0 struct multiboot_header_tag_relocatable *rel_tag;<br>
+=C2=A0 int entry_specified =3D 0, efi_entry_specified =3D 0, relocatable =
=3D 0;<br>
=C2=A0 =C2=A0grub_addr_t entry =3D 0, efi_entry =3D 0;<br>
-=C2=A0 grub_uint32_t console_required =3D 0;<br>
+=C2=A0 grub_uint32_t console_required =3D 0, min_addr =3D 0;<br>
+=C2=A0 grub_uint32_t max_addr =3D 0, preference =3D GRUB_RELOCATOR_PREFERE=
NCE_NONE;<br>
=C2=A0 =C2=A0struct multiboot_header_tag_framebuffer *fbtag =3D NULL;<br>
=C2=A0 =C2=A0int accepted_consoles =3D GRUB_MULTIBOOT_CONSOLE_EGA_TEXT;<br>
+=C2=A0 grub_size_t align =3D 0;<br>
<br>
=C2=A0 =C2=A0buffer =3D grub_malloc (MULTIBOOT_SEARCH);<br>
=C2=A0 =C2=A0if (!buffer)<br>
@@ -174,6 +178,7 @@ grub_multiboot_load (grub_file_t file, const char *file=
name)<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 case MULTIBOOT_TAG_TYPE_EF=
I_BS:<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 case MULTIBOOT_TAG_TYPE_EF=
I32_IH:<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 case MULTIBOOT_TAG_TYPE_EF=
I64_IH:<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0case MULTIBOOT_TAG_TYPE_BA=
SE_ADDR:<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 break;<br>
<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 default:<br>
@@ -215,6 +220,27 @@ grub_multiboot_load (grub_file_t file, const char *fil=
ename)<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 accepted_consoles |=3D GRUB_MULTIBOOT_CONSOLE_F=
RAMEBUFFER;<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 break;<br>
<br>
+=C2=A0 =C2=A0 =C2=A0 case MULTIBOOT_HEADER_TAG_RELOCATABLE:<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0relocatable =3D 1;<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0rel_tag =3D (struct multiboot_header_tag_reloca=
table *) tag;<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0min_addr =3D rel_tag-&gt;min_addr;<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0max_addr =3D rel_tag-&gt;max_addr;<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0align =3D rel_tag-&gt;align;<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0switch (rel_tag-&gt;preference)<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0{<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0case MULTIBOOT_LOAD_PREFERENCE_LOW:<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0preference =3D GRUB_RELOCATOR_PRE=
FERENCE_LOW;<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0break;<br>
+<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0case MULTIBOOT_LOAD_PREFERENCE_HIGH:<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0preference =3D GRUB_RELOCATOR_PRE=
FERENCE_HIGH;<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0break;<br>
+<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0default:<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0preference =3D GRUB_RELOCATOR_PRE=
FERENCE_NONE;<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0}<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0break;<br>
+<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 /* GRUB always page-aligns modules.=C2=A0 */<br=
>
=C2=A0 =C2=A0 =C2=A0 =C2=A0case MULTIBOOT_HEADER_TAG_MODULE_ALIGN:<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 break;<br>
@@ -260,15 +286,22 @@ grub_multiboot_load (grub_file_t file, const char *fi=
lename)<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0else<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 code_size =3D load_size;<br>
<br>
-=C2=A0 =C2=A0 =C2=A0 err =3D grub_relocator_alloc_chunk_addr (grub_multibo=
ot_relocator,<br>
-=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 &amp;ch, load_addr,<br>
-=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 code_size);<br>
+=C2=A0 =C2=A0 =C2=A0 if (relocatable)<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0err =3D grub_relocator_alloc_chunk_align (grub_=
multiboot_relocator, &amp;ch,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0min_addr, max_addr - code_size,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0code_size, align ? align : 1,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 =C2=A0preference, keep_bs);<br>
+=C2=A0 =C2=A0 =C2=A0 else<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0err =3D grub_relocator_alloc_chunk_addr (grub_m=
ultiboot_relocator,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 &amp;ch, load_addr,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0 code_size);<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0if (err)<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 {<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 grub_dprintf (&quot;multiboot_loader&quo=
t;, &quot;Error loading aout kludge\n&quot;);<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 grub_free (buffer);<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 return err;<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 }<br>
+=C2=A0 =C2=A0 =C2=A0 base_addr =3D get_physical_target_address (ch);<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0source =3D get_virtual_current_address (ch);<br>
<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0if ((grub_file_seek (file, offset)) =3D=3D (grub=
_off_t) -1)<br>
@@ -290,7 +323,9 @@ grub_multiboot_load (grub_file_t file, const char *file=
name)<br>
=C2=A0 =C2=A0 =C2=A0}<br>
=C2=A0 =C2=A0else<br>
=C2=A0 =C2=A0 =C2=A0{<br>
-=C2=A0 =C2=A0 =C2=A0 err =3D grub_multiboot_load_elf (file, filename, buff=
er);<br>
+=C2=A0 =C2=A0 =C2=A0 err =3D grub_multiboot_load_elf (file, filename, buff=
er,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 relocatable, min_addr,=
 max_addr,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 align, preference, &am=
p;base_addr, keep_bs);<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0if (err)<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 {<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 grub_free (buffer);<br>
@@ -303,6 +338,14 @@ grub_multiboot_load (grub_file_t file, const char *fil=
ename)<br>
=C2=A0 =C2=A0else if (entry_specified)<br>
=C2=A0 =C2=A0 =C2=A0grub_multiboot_payload_eip =3D entry;<br>
<br>
+=C2=A0 if (relocatable)<br>
+=C2=A0 =C2=A0 {<br>
+=C2=A0 =C2=A0 =C2=A0 if (base_addr &gt; min_addr)<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0grub_multiboot_payload_eip +=3D base_addr - min=
_addr;<br>
+=C2=A0 =C2=A0 =C2=A0 else<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0grub_multiboot_payload_eip -=3D min_addr - base=
_addr;<br>
+=C2=A0 =C2=A0 }<br>
+<br></blockquote><div>Why is it relative to min_addr? Sounds like it shoul=
d be just an offset from base addr. What do ET_DYN files use?=C2=A0</div><b=
lockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1px =
#ccc solid;padding-left:1ex">
=C2=A0 =C2=A0if (fbtag)<br>
=C2=A0 =C2=A0 =C2=A0err =3D grub_multiboot_set_console (GRUB_MULTIBOOT_CONS=
OLE_FRAMEBUFFER,<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 accepted_consol=
es,<br>
@@ -409,6 +452,7 @@ grub_multiboot_get_mbi_size (void)<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0+ grub_get_mu=
ltiboot_mmap_count ()<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0* sizeof (str=
uct multiboot_mmap_entry)), MULTIBOOT_TAG_ALIGN)<br>
=C2=A0 =C2=A0 =C2=A0+ ALIGN_UP (sizeof (struct multiboot_tag_framebuffer), =
MULTIBOOT_TAG_ALIGN)<br>
+=C2=A0 =C2=A0 + ALIGN_UP (sizeof (struct multiboot_tag_base_addr), MULTIBO=
OT_TAG_ALIGN)<br>
=C2=A0#ifdef GRUB_MACHINE_EFI<br>
=C2=A0#ifdef __i386__<br>
=C2=A0 =C2=A0 =C2=A0+ ALIGN_UP (sizeof (struct multiboot_tag_efi32), MULTIB=
OOT_TAG_ALIGN)<br>
@@ -698,6 +742,15 @@ grub_multiboot_make_mbi (grub_uint32_t *target)<br>
=C2=A0 =C2=A0ptrorig +=3D (2 * sizeof (grub_uint32_t)) / sizeof (grub_prope=
rly_aligned_t);<br>
<br>
=C2=A0 =C2=A0{<br>
+=C2=A0 =C2=A0 struct multiboot_tag_base_addr *tag =3D (struct multiboot_ta=
g_base_addr *) ptrorig;<br>
+=C2=A0 =C2=A0 tag-&gt;type =3D MULTIBOOT_TAG_TYPE_BASE_ADDR;<br>
+=C2=A0 =C2=A0 tag-&gt;size =3D sizeof (struct multiboot_tag_base_addr);<br=
>
+=C2=A0 =C2=A0 tag-&gt;base_addr =3D base_addr;<br>
+=C2=A0 =C2=A0 ptrorig +=3D ALIGN_UP (tag-&gt;size, MULTIBOOT_TAG_ALIGN)<br=
>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0/ sizeof (grub_properly_aligned_t);<br>
+=C2=A0 }<br>
+<br>
+=C2=A0 {<br>
=C2=A0 =C2=A0 =C2=A0struct multiboot_tag_string *tag =3D (struct multiboot_=
tag_string *) ptrorig;<br>
=C2=A0 =C2=A0 =C2=A0tag-&gt;type =3D MULTIBOOT_TAG_TYPE_CMDLINE;<br>
=C2=A0 =C2=A0 =C2=A0tag-&gt;size =3D sizeof (struct multiboot_tag_string) +=
 cmdline_size;<br>
diff --git a/include/grub/multiboot.h b/include/grub/multiboot.h<br>
index e13c084..ec322b0 100644<br>
--- a/include/grub/multiboot.h<br>
+++ b/include/grub/multiboot.h<br>
@@ -94,7 +94,9 @@ grub_multiboot_load (grub_file_t file, const char *filena=
me);<br>
=C2=A0/* Load ELF32 or ELF64.=C2=A0 */<br>
=C2=A0grub_err_t<br>
=C2=A0grub_multiboot_load_elf (grub_file_t file, const char *filename,<br>
-=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 void *buffer);<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 void *buffer, int relocatable, grub_uint32_t min_addr,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 grub_uint32_t max_addr, grub_size_t align, grub_uint32_t prefere=
nce,<br>
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A0 grub_uint32_t *base_addr, int avoid_efi_boot_services);<br>
=C2=A0extern grub_size_t grub_multiboot_pure_size;<br>
=C2=A0extern grub_size_t grub_multiboot_alloc_mbi;<br>
=C2=A0extern grub_uint32_t grub_multiboot_payload_eip;<br>
diff --git a/include/multiboot2.h b/include/multiboot2.h<br>
index 36a174f..c09bdbc 100644<br>
--- a/include/multiboot2.h<br>
+++ b/include/multiboot2.h<br>
@@ -62,6 +62,7 @@<br>
=C2=A0#define MULTIBOOT_TAG_TYPE_EFI_BS=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 18<br>
=C2=A0#define MULTIBOOT_TAG_TYPE_EFI32_IH=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0=
 19<br>
=C2=A0#define MULTIBOOT_TAG_TYPE_EFI64_IH=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0=
 20<br>
+#define MULTIBOOT_TAG_TYPE_BASE_ADDR=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A021<b=
r>
<br>
=C2=A0#define MULTIBOOT_HEADER_TAG_END=C2=A0 0<br>
=C2=A0#define MULTIBOOT_HEADER_TAG_INFORMATION_REQUEST=C2=A0 1<br>
@@ -72,11 +73,16 @@<br>
=C2=A0#define MULTIBOOT_HEADER_TAG_MODULE_ALIGN=C2=A0 6<br>
=C2=A0#define MULTIBOOT_HEADER_TAG_EFI_BS=C2=A0 7<br>
=C2=A0#define MULTIBOOT_HEADER_TAG_ENTRY_ADDRESS_EFI64=C2=A0 9<br>
+#define MULTIBOOT_HEADER_TAG_RELOCATABLE=C2=A0 10<br>
<br>
=C2=A0#define MULTIBOOT_ARCHITECTURE_I386=C2=A0 0<br>
=C2=A0#define MULTIBOOT_ARCHITECTURE_MIPS32=C2=A0 4<br>
=C2=A0#define MULTIBOOT_HEADER_TAG_OPTIONAL 1<br>
<br>
+#define MULTIBOOT_LOAD_PREFERENCE_NONE 0<br>
+#define MULTIBOOT_LOAD_PREFERENCE_LOW 1<br>
+#define MULTIBOOT_LOAD_PREFERENCE_HIGH 2<br>
+<br>
=C2=A0#define MULTIBOOT_CONSOLE_FLAGS_CONSOLE_REQUIRED 1<br>
=C2=A0#define MULTIBOOT_CONSOLE_FLAGS_EGA_TEXT_SUPPORTED 2<br>
<br>
@@ -161,6 +167,17 @@ struct multiboot_header_tag_module_align<br>
=C2=A0 =C2=A0multiboot_uint32_t size;<br>
=C2=A0};<br>
<br>
+struct multiboot_header_tag_relocatable<br>
+{<br>
+=C2=A0 multiboot_uint16_t type;<br>
+=C2=A0 multiboot_uint16_t flags;<br>
+=C2=A0 multiboot_uint32_t size;<br>
+=C2=A0 multiboot_uint32_t min_addr;<br>
+=C2=A0 multiboot_uint32_t max_addr;<br>
+=C2=A0 multiboot_uint32_t align;<br>
+=C2=A0 multiboot_uint32_t preference;<br>
+};<br>
+<br>
=C2=A0struct multiboot_color<br>
=C2=A0{<br>
=C2=A0 =C2=A0multiboot_uint8_t red;<br>
@@ -387,6 +404,13 @@ struct multiboot_tag_efi64_ih<br>
=C2=A0 =C2=A0multiboot_uint64_t pointer;<br>
=C2=A0};<br>
<br>
+struct multiboot_tag_base_addr<br>
+{<br>
+=C2=A0 multiboot_uint32_t type;<br>
+=C2=A0 multiboot_uint32_t size;<br>
+=C2=A0 multiboot_uint32_t base_addr;<br>
+};<br>
+<br>
=C2=A0#endif /* ! ASM_FILE */<br>
<br>
=C2=A0#endif /* ! MULTIBOOT_HEADER */<br>
--<br>
1.7.10.4<br>
<br>
</blockquote><br><br>-- <br>Regards<br>Vladimir &#39;phcoder&#39; Serbinenk=
o<br><br>

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