From 92fca67cf55010923fb5d45a1aae7b3b726be5bd Mon Sep 17 00:00:00 2001
From: okuji <okuji@localhost>
Date: Tue, 18 Apr 2000 11:22:07 +0000
Subject: [PATCH] make the LBA support bitmap checks configurable at the
 installation time.

---
 ChangeLog            |  55 ++++++++++++++
 INSTALL              |   8 --
 NEWS                 |   6 ++
 acconfig.h           |   3 -
 config.h.in          |  57 ++++++--------
 configure            | 174 +++++++++++++++++++------------------------
 configure.in         |   9 ---
 docs/grub-install.8  |   4 +
 stage1/stage1.S      |  17 +++--
 stage1/stage1.h      |  23 +++---
 stage2/asm.S         |   2 +
 stage2/bios.c        |   7 +-
 stage2/builtins.c    | 117 +++++++++++++++++++----------
 stage2/shared.h      |  10 ++-
 util/grub-install.in |   7 +-
 15 files changed, 283 insertions(+), 216 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index fd587de80..97d6e30c3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,58 @@
+2000-04-17  OKUJI Yoshinori  <okuji@gnu.org>
+
+	The user doesn't have to recompile GRUB for his/her buggy BIOS
+	any longer. It is configurable to ignore the LBA support bitmap
+	at the installation time.
+	
+	* stage1/stage1.S (force_lba): New variable.
+	(stage2_address): Moved forwards, to align some variables in
+	natural boundaries.
+	(real_start): Check if FORCE_LBA is non-zero, if so, jump to
+	skip_lba_bitmap_check, otherwise, check if bit 0 of the support
+	bitmap is non-zero.
+	Don't use #ifdef for CHECK_LBA_SUPPORT_BITMAP.
+	(skip_lba_bitmap_check): New label.
+	* stage1/stage1.h (COMPAT_VERSION_MINOR): Set to 1.
+	(STAGE1_FORCE_LBA): New macro.
+	(STAGE1_STAGE2_ADDRESS): Set to 0x42.
+	(STAGE1_STAGE2_SECTOR): Set to 0x44.
+	(STAGE1_STAGE2_SEGMENT): Set to 0x48.
+	* stage2/asm.S (force_lba): New variable.
+	* stage2/bios.c (get_diskinfo): Don't use #ifdef for
+	CHECK_LBA_SUPPORT_BITMAP. Instead, check if FORCE_LBA is
+	non-zero. If so, don't check the bit 0 of DRP.FLAG.
+	* stage2/builtins.c (install_func): Check if a new option
+	`--force-lba' is specified. If specified, set IS_FORCE_LBA to 1
+	and set ARG to a value returned by skip_to. Otherwise,
+	IS_FORCE_LBA is zero.
+	Set the "force LBA" flag in STAGE1_BUFFER (the offset is
+	STAGE1_FORCE_LBA) to IS_FORCE_LBA.
+	Likewise, set the "force LBA" flag in STAGE2_SECOND_BUFFER
+	(the offset is STAGE2_FORCE_LBA) to IS_FORCE_LBA.
+	If IS_STAGE1_5 is true, then modify the Stage2, regardless of
+	the presence of the option REAL_CONFIG_FILE. Set the "force LBA"
+	flag in SCRATCHADDR (the offset is STAGE2_FORCE_LBA) to
+	IS_FORCE_LBA.
+	(builtin_install): Added description about `--force-lba' into
+	the docs.
+	(setup_func): Check if `--force-lba' is specified in ARG. If
+	specified, set IS_FORCE_LBA to 1 and set ARG to a value returned
+	by skip_to. Otherwise, IS_FORCE_LBA is zero.
+	If IS_FORCE_LBA is true, prepend "--force-lba " to CMD_ARG.
+	(builtin_setup): Added descriptions about `--force-lba' into the
+	docs.
+	* stage2/shared.h (STAGE2_FORCE_LBA): New macro.
+	(STAGE2_VER_STR_OFFS): Set to 0xe.
+	(force_lba): Declared.
+	* util/grub-install.in (force_lba): New variable. Set to an
+	empty sting by default.
+	(usage): Added a description about `--force-lba'.
+	(--force-lba): Checked in the option handling code. If
+	specified, set FORCE_LBA to "--force-lba".
+	Run the command "setup" with $force_lba added before
+	$install_drive.
+	* configure.in (--disable-lba-support-bitmap): Removed.
+	
 2000-04-15  OKUJI Yoshinori  <okuji@gnu.org>
 
 	* util/grub-install.in (root_device): Append `/' to ${rootdir},
diff --git a/INSTALL b/INSTALL
index f2ad40eed..764eb262a 100644
--- a/INSTALL
+++ b/INSTALL
@@ -188,14 +188,6 @@ operates.
      confusing) to the casual installer. If you are a GRUB developer,
      it is a good idea to specify this option.
 
-`--disable-lba-support-bitmap-check'
-     Disable the check for LBA support bitmap. Specify this option
-     if you are sure that your BIOS has the INT 13 extension support,
-     but GRUB doesn't access your drives in LBA mode. This is
-     necessary because an incorrect LBA support bitmap is returned in
-     several buggy BIOSes. You can check if GRUB recognizes the INT 13
-     extension support by the command `geometry'.
-
 `--disable-ext2fs'
      Omit the ext2fs support in Stage 2.
 
diff --git a/NEWS b/NEWS
index fa122233c..f48f0a126 100644
--- a/NEWS
+++ b/NEWS
@@ -10,6 +10,12 @@ New in 0.5.95 - XXXX-XX-XX:
   to load a NetBSD ELF kernel, because GRUB can automatically determine
   a kernel type in the other cases.
 * ReiserFS support is added.
+* Added a new option `--force-lba' into the command "install". This
+  option disables some sanity checks for LBA mode (but not all). If you
+  are sure that your machine supports LBA mode but GRUB doesn't work in
+  LBA mode, you should specify it. It is necessary if your BIOS is too
+  buggy. In the previous version, it was a compile-time option, but you
+  don't have to recompile GRUB any longer.
 
 New in 0.5.94 - 2000-03-06:
 * Stage 1 supports both the LBA mode and the CHS mode.
diff --git a/acconfig.h b/acconfig.h
index da4d4c9b7..218aa62e5 100644
--- a/acconfig.h
+++ b/acconfig.h
@@ -24,6 +24,3 @@
 
 /* Defined if _end is defined.  */
 #undef HAVE_USCORE_END_SYMBOL
-
-/* Defined if --disable-lba-support-bitmap is specified.  */
-#undef CHECK_LBA_SUPPORT_BITMAP
diff --git a/config.h.in b/config.h.in
index 230b7fab2..7bd4b3e9b 100644
--- a/config.h.in
+++ b/config.h.in
@@ -24,8 +24,29 @@
 /* Defined if _end is defined.  */
 #undef HAVE_USCORE_END_SYMBOL
 
-/* Defined if --disable-lba-support-bitmap is specified.  */
-#undef CHECK_LBA_SUPPORT_BITMAP
+/* Define if you have the <curses.h> header file.  */
+#undef HAVE_CURSES_H
+
+/* Define if you have the <ncurses.h> header file.  */
+#undef HAVE_NCURSES_H
+
+/* Define if you have the <ncurses/curses.h> header file.  */
+#undef HAVE_NCURSES_CURSES_H
+
+/* Define if you have the <string.h> header file.  */
+#undef HAVE_STRING_H
+
+/* Define if you have the <strings.h> header file.  */
+#undef HAVE_STRINGS_H
+
+/* Name of package */
+#undef PACKAGE
+
+/* Version number of package */
+#undef VERSION
+
+/* Define if C symbols get an underscore after compilation */
+#undef HAVE_ASM_USCORE
 
 /* Define it to "addr32" or "addr32;" to make GAS happy */
 #undef ADDR32
@@ -33,38 +54,6 @@
 /* Define it to "data32" or "data32;" to make GAS happy */
 #undef DATA32
 
-/* Define if C symbols get an underscore after compilation */
-#undef HAVE_ASM_USCORE
-
-/* Define if you have the <curses.h> header file. */
-#undef HAVE_CURSES_H
-
-/* Define if you have the `curses' library (-lcurses). */
-#undef HAVE_LIBCURSES
-
-/* Define if you have the `ncurses' library (-lncurses). */
-#undef HAVE_LIBNCURSES
-
-/* Define if you have the `util' library (-lutil). */
-#undef HAVE_LIBUTIL
-
-/* Define if you have the <ncurses/curses.h> header file. */
-#undef HAVE_NCURSES_CURSES_H
-
-/* Define if you have the <ncurses.h> header file. */
-#undef HAVE_NCURSES_H
-
 /* Define if opendisk() in -lutil can be used */
 #undef HAVE_OPENDISK
 
-/* Define if you have the <strings.h> header file. */
-#undef HAVE_STRINGS_H
-
-/* Define if you have the <string.h> header file. */
-#undef HAVE_STRING_H
-
-/* Name of package */
-#undef PACKAGE
-
-/* Version number of package */
-#undef VERSION
diff --git a/configure b/configure
index bce781531..472687476 100644
--- a/configure
+++ b/configure
@@ -21,9 +21,6 @@ ac_help="$ac_help
   --with-binutils=DIR     search the directory DIR to find binutils"
 ac_help="$ac_help
   --without-curses        do not use curses"
-ac_help="$ac_help
-  --disable-lba-support-bitmap-check
-                          disable a check for LBA support bitmap"
 ac_help="$ac_help
   --disable-ext2fs        disable ext2fs support in Stage 2"
 ac_help="$ac_help
@@ -647,7 +644,7 @@ ac_configure=$ac_aux_dir/configure # This should be Cygnus configure.
 # SVR4 /usr/ucb/install, which tries to use the nonexistent group "staff"
 # ./install, which can be erroneously created by make from ./install.sh.
 echo $ac_n "checking for a BSD compatible install""... $ac_c" 1>&6
-echo "configure:651: checking for a BSD compatible install" >&5
+echo "configure:648: checking for a BSD compatible install" >&5
 if test -z "$INSTALL"; then
 if eval "test \"`echo '$''{'ac_cv_path_install'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -700,7 +697,7 @@ test -z "$INSTALL_SCRIPT" && INSTALL_SCRIPT='${INSTALL_PROGRAM}'
 test -z "$INSTALL_DATA" && INSTALL_DATA='${INSTALL} -m 644'
 
 echo $ac_n "checking whether build environment is sane""... $ac_c" 1>&6
-echo "configure:704: checking whether build environment is sane" >&5
+echo "configure:701: checking whether build environment is sane" >&5
 # Just in case
 sleep 1
 echo timestamp > conftestfile
@@ -772,7 +769,7 @@ do
 # Extract the first word of "$ac_prog", so it can be a program name with args.
 set dummy $ac_prog; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:776: checking for $ac_word" >&5
+echo "configure:773: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_AWK'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -802,7 +799,7 @@ test -n "$AWK" && break
 done
 
 echo $ac_n "checking whether ${MAKE-make} sets \${MAKE}""... $ac_c" 1>&6
-echo "configure:806: checking whether ${MAKE-make} sets \${MAKE}" >&5
+echo "configure:803: checking whether ${MAKE-make} sets \${MAKE}" >&5
 set dummy ${MAKE-make}; ac_make=`echo "$2" | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_prog_make_${ac_make}_set'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -937,7 +934,7 @@ else { echo "configure: error: can not run $ac_config_sub" 1>&2; exit 1; }
 fi
 
 echo $ac_n "checking host system type""... $ac_c" 1>&6
-echo "configure:941: checking host system type" >&5
+echo "configure:938: checking host system type" >&5
 
 host_alias=$host
 case "$host_alias" in
@@ -971,7 +968,7 @@ esac
 #
 
 echo $ac_n "checking whether to enable maintainer-specific portions of Makefiles""... $ac_c" 1>&6
-echo "configure:975: checking whether to enable maintainer-specific portions of Makefiles" >&5
+echo "configure:972: checking whether to enable maintainer-specific portions of Makefiles" >&5
     # Check whether --enable-maintainer-mode or --disable-maintainer-mode was given.
 if test "${enable_maintainer_mode+set}" = set; then
   enableval="$enable_maintainer_mode"
@@ -997,7 +994,7 @@ if test "x$enable_maintainer_mode" = xyes; then
   # Extract the first word of "perl", so it can be a program name with args.
 set dummy perl; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1001: checking for $ac_word" >&5
+echo "configure:998: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_path_PERL'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1044,7 +1041,7 @@ fi
 #
 
 echo $ac_n "checking build system type""... $ac_c" 1>&6
-echo "configure:1048: checking build system type" >&5
+echo "configure:1045: checking build system type" >&5
 
 build_alias=$build
 case "$build_alias" in
@@ -1070,7 +1067,7 @@ fi
 # Extract the first word of "${ac_tool_prefix}gcc", so it can be a program name with args.
 set dummy ${ac_tool_prefix}gcc; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1074: checking for $ac_word" >&5
+echo "configure:1071: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_CC'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1102,7 +1099,7 @@ fi
 # Extract the first word of "gcc", so it can be a program name with args.
 set dummy gcc; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1106: checking for $ac_word" >&5
+echo "configure:1103: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_CC'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1132,7 +1129,7 @@ if test -z "$CC"; then
   # Extract the first word of "cc", so it can be a program name with args.
 set dummy cc; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1136: checking for $ac_word" >&5
+echo "configure:1133: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_CC'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1183,7 +1180,7 @@ fi
       # Extract the first word of "cl", so it can be a program name with args.
 set dummy cl; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1187: checking for $ac_word" >&5
+echo "configure:1184: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_CC'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1215,7 +1212,7 @@ fi
 fi
 
 echo $ac_n "checking whether the C compiler ($CC $CFLAGS $LDFLAGS) works""... $ac_c" 1>&6
-echo "configure:1219: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) works" >&5
+echo "configure:1216: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) works" >&5
 
 ac_ext=c
 # CFLAGS is not in ac_cpp because -g, -O, etc. are not valid cpp options.
@@ -1226,12 +1223,12 @@ cross_compiling=$ac_cv_prog_cc_cross
 
 cat > conftest.$ac_ext << EOF
 
-#line 1230 "configure"
+#line 1227 "configure"
 #include "confdefs.h"
 
 main(){return(0);}
 EOF
-if { (eval echo configure:1235: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1232: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   ac_cv_prog_cc_works=yes
   # If we can't run a trivial program, we are probably using a cross compiler.
   if (./conftest; exit) 2>/dev/null; then
@@ -1257,12 +1254,12 @@ if test $ac_cv_prog_cc_works = no; then
   { echo "configure: error: installation or configuration problem: C compiler cannot create executables." 1>&2; exit 1; }
 fi
 echo $ac_n "checking whether the C compiler ($CC $CFLAGS $LDFLAGS) is a cross-compiler""... $ac_c" 1>&6
-echo "configure:1261: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) is a cross-compiler" >&5
+echo "configure:1258: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) is a cross-compiler" >&5
 echo "$ac_t""$ac_cv_prog_cc_cross" 1>&6
 cross_compiling=$ac_cv_prog_cc_cross
 
 echo $ac_n "checking whether we are using GNU C""... $ac_c" 1>&6
-echo "configure:1266: checking whether we are using GNU C" >&5
+echo "configure:1263: checking whether we are using GNU C" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_gcc'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1271,7 +1268,7 @@ else
   yes;
 #endif
 EOF
-if { ac_try='${CC-cc} -E conftest.c'; { (eval echo configure:1275: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } | egrep yes >/dev/null 2>&1; then
+if { ac_try='${CC-cc} -E conftest.c'; { (eval echo configure:1272: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } | egrep yes >/dev/null 2>&1; then
   ac_cv_prog_gcc=yes
 else
   ac_cv_prog_gcc=no
@@ -1290,7 +1287,7 @@ ac_test_CFLAGS="${CFLAGS+set}"
 ac_save_CFLAGS="$CFLAGS"
 CFLAGS=
 echo $ac_n "checking whether ${CC-cc} accepts -g""... $ac_c" 1>&6
-echo "configure:1294: checking whether ${CC-cc} accepts -g" >&5
+echo "configure:1291: checking whether ${CC-cc} accepts -g" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_cc_g'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1323,7 +1320,7 @@ fi
 
 
 echo $ac_n "checking how to run the C preprocessor""... $ac_c" 1>&6
-echo "configure:1327: checking how to run the C preprocessor" >&5
+echo "configure:1324: checking how to run the C preprocessor" >&5
 # On Suns, sometimes $CPP names a directory.
 if test -n "$CPP" && test -d "$CPP"; then
   CPP=
@@ -1338,13 +1335,13 @@ else
   # On the NeXT, cc -E runs the code through the compiler's parser,
   # not just through cpp.
   cat > conftest.$ac_ext <<EOF
-#line 1342 "configure"
+#line 1339 "configure"
 #include "confdefs.h"
 #include <assert.h>
 Syntax Error
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1348: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1345: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   :
@@ -1355,13 +1352,13 @@ else
   rm -rf conftest*
   CPP="${CC-cc} -E -traditional-cpp"
   cat > conftest.$ac_ext <<EOF
-#line 1359 "configure"
+#line 1356 "configure"
 #include "confdefs.h"
 #include <assert.h>
 Syntax Error
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1365: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1362: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   :
@@ -1372,13 +1369,13 @@ else
   rm -rf conftest*
   CPP="${CC-cc} -nologo -E"
   cat > conftest.$ac_ext <<EOF
-#line 1376 "configure"
+#line 1373 "configure"
 #include "confdefs.h"
 #include <assert.h>
 Syntax Error
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1382: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1379: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   :
@@ -1411,7 +1408,7 @@ echo "$ac_t""$CPP" 1>&6
 depcc="$CC"
 depcpp="$CPP"
 echo $ac_n "checking dependency style of $depcc""... $ac_c" 1>&6
-echo "configure:1415: checking dependency style of $depcc" >&5
+echo "configure:1412: checking dependency style of $depcc" >&5
 if eval "test \"`echo '$''{'am_cv_CC_dependencies_compiler_type'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1467,7 +1464,7 @@ if test "x$with_binutils" != x; then
   # Extract the first word of "ranlib", so it can be a program name with args.
 set dummy ranlib; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1471: checking for $ac_word" >&5
+echo "configure:1468: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_path_RANLIB'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1504,7 +1501,7 @@ else
   # Extract the first word of "ranlib", so it can be a program name with args.
 set dummy ranlib; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1508: checking for $ac_word" >&5
+echo "configure:1505: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_RANLIB'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1544,7 +1541,7 @@ if test "x$ac_cv_prog_gcc" = xyes; then
     STAGE1_CFLAGS="-O2"
     GRUB_CFLAGS="-O2"
     echo $ac_n "checking whether optimization for size works""... $ac_c" 1>&6
-echo "configure:1548: checking whether optimization for size works" >&5
+echo "configure:1545: checking whether optimization for size works" >&5
 if eval "test \"`echo '$''{'size_flag'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1552,14 +1549,14 @@ else
       saved_CFLAGS=$CFLAGS
       CFLAGS="-Os -g"
       cat > conftest.$ac_ext <<EOF
-#line 1556 "configure"
+#line 1553 "configure"
 #include "confdefs.h"
 
 int main() {
 
 ; return 0; }
 EOF
-if { (eval echo configure:1563: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:1560: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   size_flag=yes
 else
@@ -1593,7 +1590,7 @@ if test "x$with_binutils" != x; then
   # Extract the first word of "objcopy", so it can be a program name with args.
 set dummy objcopy; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1597: checking for $ac_word" >&5
+echo "configure:1594: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_path_OBJCOPY'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1629,7 +1626,7 @@ else
   # Extract the first word of "${ac_tool_prefix}objcopy", so it can be a program name with args.
 set dummy ${ac_tool_prefix}objcopy; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1633: checking for $ac_word" >&5
+echo "configure:1630: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_OBJCOPY'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1663,7 +1660,7 @@ fi
 # Defined in acinclude.m4.
 
 echo $ac_n "checking if C symbols get an underscore after compilation""... $ac_c" 1>&6
-echo "configure:1667: checking if C symbols get an underscore after compilation" >&5
+echo "configure:1664: checking if C symbols get an underscore after compilation" >&5
 if eval "test \"`echo '$''{'grub_cv_asm_uscore'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1676,7 +1673,7 @@ func (int *list)
 }
 EOF
 
-if { ac_try='${CC-cc} ${CFLAGS} -S conftest.c'; { (eval echo configure:1680: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } && test -s conftest.s; then
+if { ac_try='${CC-cc} ${CFLAGS} -S conftest.c'; { (eval echo configure:1677: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } && test -s conftest.s; then
   true
 else
   { echo "configure: error: ${CC-cc} failed to produce assembly code" 1>&2; exit 1; }
@@ -1702,7 +1699,7 @@ fi
 echo "$ac_t""$grub_cv_asm_uscore" 1>&6
 
 echo $ac_n "checking whether ${OBJCOPY} works for absolute addresses""... $ac_c" 1>&6
-echo "configure:1706: checking whether ${OBJCOPY} works for absolute addresses" >&5
+echo "configure:1703: checking whether ${OBJCOPY} works for absolute addresses" >&5
 if eval "test \"`echo '$''{'grub_cv_prog_objcopy_absolute'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1714,21 +1711,21 @@ cmain (void)
 }
 EOF
 
-if { (eval echo configure:1718: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; } && test -s conftest.o; then :
+if { (eval echo configure:1715: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; } && test -s conftest.o; then :
 else
   { echo "configure: error: ${CC-cc} cannot compile C source code" 1>&2; exit 1; }
 fi
 grub_cv_prog_objcopy_absolute=yes
 for link_addr in 2000 8000 7C00; do
-  if { ac_try='${CC-cc} ${CFLAGS} -nostdlib -Wl,-N -Wl,-Ttext -Wl,$link_addr conftest.o -o conftest.exec'; { (eval echo configure:1724: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; }; then :
+  if { ac_try='${CC-cc} ${CFLAGS} -nostdlib -Wl,-N -Wl,-Ttext -Wl,$link_addr conftest.o -o conftest.exec'; { (eval echo configure:1721: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; }; then :
   else
     { echo "configure: error: ${CC-cc} cannot link at address $link_addr" 1>&2; exit 1; }
   fi
-  if { ac_try='${OBJCOPY-objcopy} -O binary conftest.exec conftest'; { (eval echo configure:1728: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; }; then :
+  if { ac_try='${OBJCOPY-objcopy} -O binary conftest.exec conftest'; { (eval echo configure:1725: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; }; then :
   else
     { echo "configure: error: ${OBJCOPY-objcopy} cannot create binary files" 1>&2; exit 1; }
   fi
-  if test ! -f conftest.old || { ac_try='cmp -s conftest.old conftest'; { (eval echo configure:1732: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; }; then
+  if test ! -f conftest.old || { ac_try='cmp -s conftest.old conftest'; { (eval echo configure:1729: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; }; then
     mv -f conftest conftest.old
   else
     grub_cv_prog_objcopy_absolute=no
@@ -1745,7 +1742,7 @@ fi
 
 
 echo $ac_n "checking whether addr32 must be in the same line as the instruction""... $ac_c" 1>&6
-echo "configure:1749: checking whether addr32 must be in the same line as the instruction" >&5
+echo "configure:1746: checking whether addr32 must be in the same line as the instruction" >&5
 if eval "test \"`echo '$''{'grub_cv_asm_prefix_requirement'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1754,7 +1751,7 @@ else
 l1:	addr32	movb	%al, l1
 EOF
 
-if { ac_try='${CC-cc} ${CFLAGS} -c conftest.s'; { (eval echo configure:1758: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } && test -s conftest.o; then
+if { ac_try='${CC-cc} ${CFLAGS} -c conftest.s'; { (eval echo configure:1755: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } && test -s conftest.o; then
   grub_cv_asm_prefix_requirement=yes
 else
   grub_cv_asm_prefix_requirement=no
@@ -1786,7 +1783,7 @@ echo "$ac_t""$grub_cv_asm_prefix_requirement" 1>&6
 
 
 echo $ac_n "checking for .code16 addr32 assembler support""... $ac_c" 1>&6
-echo "configure:1790: checking for .code16 addr32 assembler support" >&5
+echo "configure:1787: checking for .code16 addr32 assembler support" >&5
 if eval "test \"`echo '$''{'grub_cv_asm_addr32'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1801,7 +1798,7 @@ else
   sed -e s/@ADDR32@/addr32\;/ < conftest.s.in > conftest.s
 fi
 
-if { ac_try='${CC-cc} ${CFLAGS} -c conftest.s'; { (eval echo configure:1805: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } && test -s conftest.o; then
+if { ac_try='${CC-cc} ${CFLAGS} -c conftest.s'; { (eval echo configure:1802: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } && test -s conftest.o; then
   grub_cv_asm_addr32=yes
 else
   grub_cv_asm_addr32=no
@@ -1818,19 +1815,19 @@ fi
 
 
 echo $ac_n "checking if start is defined by the compiler""... $ac_c" 1>&6
-echo "configure:1822: checking if start is defined by the compiler" >&5
+echo "configure:1819: checking if start is defined by the compiler" >&5
 if eval "test \"`echo '$''{'grub_cv_check_start_symbol'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1827 "configure"
+#line 1824 "configure"
 #include "confdefs.h"
 
 int main() {
 asm ("incl start")
 ; return 0; }
 EOF
-if { (eval echo configure:1834: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1831: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   grub_cv_check_start_symbol=yes
 else
@@ -1854,19 +1851,19 @@ echo "$ac_t""$grub_cv_check_start_symbol" 1>&6
 
 
 echo $ac_n "checking if _start is defined by the compiler""... $ac_c" 1>&6
-echo "configure:1858: checking if _start is defined by the compiler" >&5
+echo "configure:1855: checking if _start is defined by the compiler" >&5
 if eval "test \"`echo '$''{'grub_cv_check_uscore_start_symbol'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1863 "configure"
+#line 1860 "configure"
 #include "confdefs.h"
 
 int main() {
 asm ("incl _start")
 ; return 0; }
 EOF
-if { (eval echo configure:1870: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1867: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   grub_cv_check_uscore_start_symbol=yes
 else
@@ -1895,19 +1892,19 @@ fi
 
 
 echo $ac_n "checking if __bss_start is defined by the compiler""... $ac_c" 1>&6
-echo "configure:1899: checking if __bss_start is defined by the compiler" >&5
+echo "configure:1896: checking if __bss_start is defined by the compiler" >&5
 if eval "test \"`echo '$''{'grub_cv_check_uscore_uscore_bss_start_symbol'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1904 "configure"
+#line 1901 "configure"
 #include "confdefs.h"
 
 int main() {
 asm ("incl __bss_start")
 ; return 0; }
 EOF
-if { (eval echo configure:1911: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1908: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   grub_cv_check_uscore_uscore_bss_start_symbol=yes
 else
@@ -1931,19 +1928,19 @@ echo "$ac_t""$grub_cv_check_uscore_uscore_bss_start_symbol" 1>&6
 
 
 echo $ac_n "checking if _edata is defined by the compiler""... $ac_c" 1>&6
-echo "configure:1935: checking if _edata is defined by the compiler" >&5
+echo "configure:1932: checking if _edata is defined by the compiler" >&5
 if eval "test \"`echo '$''{'grub_cv_check_uscore_edata_symbol'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1940 "configure"
+#line 1937 "configure"
 #include "confdefs.h"
 
 int main() {
 asm ("incl _edata")
 ; return 0; }
 EOF
-if { (eval echo configure:1947: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1944: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   grub_cv_check_uscore_edata_symbol=yes
 else
@@ -1967,19 +1964,19 @@ echo "$ac_t""$grub_cv_check_uscore_edata_symbol" 1>&6
 
 
 echo $ac_n "checking if edata is defined by the compiler""... $ac_c" 1>&6
-echo "configure:1971: checking if edata is defined by the compiler" >&5
+echo "configure:1968: checking if edata is defined by the compiler" >&5
 if eval "test \"`echo '$''{'grub_cv_check_edata_symbol'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1976 "configure"
+#line 1973 "configure"
 #include "confdefs.h"
 
 int main() {
 asm ("incl edata")
 ; return 0; }
 EOF
-if { (eval echo configure:1983: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1980: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   grub_cv_check_edata_symbol=yes
 else
@@ -2009,19 +2006,19 @@ fi
 
 
 echo $ac_n "checking if end is defined by the compiler""... $ac_c" 1>&6
-echo "configure:2013: checking if end is defined by the compiler" >&5
+echo "configure:2010: checking if end is defined by the compiler" >&5
 if eval "test \"`echo '$''{'grub_cv_check_end_symbol'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2018 "configure"
+#line 2015 "configure"
 #include "confdefs.h"
 
 int main() {
 asm ("incl end")
 ; return 0; }
 EOF
-if { (eval echo configure:2025: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2022: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   grub_cv_check_end_symbol=yes
 else
@@ -2045,19 +2042,19 @@ echo "$ac_t""$grub_cv_check_end_symbol" 1>&6
 
 
 echo $ac_n "checking if _end is defined by the compiler""... $ac_c" 1>&6
-echo "configure:2049: checking if _end is defined by the compiler" >&5
+echo "configure:2046: checking if _end is defined by the compiler" >&5
 if eval "test \"`echo '$''{'grub_cv_check_uscore_end_symbol'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2054 "configure"
+#line 2051 "configure"
 #include "confdefs.h"
 
 int main() {
 asm ("incl _end")
 ; return 0; }
 EOF
-if { (eval echo configure:2061: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2058: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   grub_cv_check_uscore_end_symbol=yes
 else
@@ -2095,7 +2092,7 @@ fi
 # Get the filename or the whole disk and open it.
 # Known to work on NetBSD.
 echo $ac_n "checking for opendisk in -lutil""... $ac_c" 1>&6
-echo "configure:2099: checking for opendisk in -lutil" >&5
+echo "configure:2096: checking for opendisk in -lutil" >&5
 ac_lib_var=`echo util'_'opendisk | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -2103,7 +2100,7 @@ else
   ac_save_LIBS="$LIBS"
 LIBS="-lutil  $LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 2107 "configure"
+#line 2104 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -2114,7 +2111,7 @@ int main() {
 opendisk()
 ; return 0; }
 EOF
-if { (eval echo configure:2118: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2115: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_lib_$ac_lib_var=yes"
 else
@@ -2142,7 +2139,7 @@ fi
 # Unless the user specify --without-curses, check for curses.
 if test "x$with_curses" != "xno"; then
   echo $ac_n "checking for wgetch in -lncurses""... $ac_c" 1>&6
-echo "configure:2146: checking for wgetch in -lncurses" >&5
+echo "configure:2143: checking for wgetch in -lncurses" >&5
 ac_lib_var=`echo ncurses'_'wgetch | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -2150,7 +2147,7 @@ else
   ac_save_LIBS="$LIBS"
 LIBS="-lncurses  $LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 2154 "configure"
+#line 2151 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -2161,7 +2158,7 @@ int main() {
 wgetch()
 ; return 0; }
 EOF
-if { (eval echo configure:2165: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2162: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_lib_$ac_lib_var=yes"
 else
@@ -2184,7 +2181,7 @@ EOF
 else
   echo "$ac_t""no" 1>&6
 echo $ac_n "checking for wgetch in -lcurses""... $ac_c" 1>&6
-echo "configure:2188: checking for wgetch in -lcurses" >&5
+echo "configure:2185: checking for wgetch in -lcurses" >&5
 ac_lib_var=`echo curses'_'wgetch | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -2192,7 +2189,7 @@ else
   ac_save_LIBS="$LIBS"
 LIBS="-lcurses  $LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 2196 "configure"
+#line 2193 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -2203,7 +2200,7 @@ int main() {
 wgetch()
 ; return 0; }
 EOF
-if { (eval echo configure:2207: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2204: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_lib_$ac_lib_var=yes"
 else
@@ -2238,17 +2235,17 @@ for ac_hdr in string.h strings.h ncurses/curses.h ncurses.h curses.h
 do
 ac_safe=`echo "$ac_hdr" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for $ac_hdr""... $ac_c" 1>&6
-echo "configure:2242: checking for $ac_hdr" >&5
+echo "configure:2239: checking for $ac_hdr" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2247 "configure"
+#line 2244 "configure"
 #include "confdefs.h"
 #include <$ac_hdr>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:2252: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:2249: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -2277,21 +2274,6 @@ done
 
 # Check for user options.
 
-# some compile-time options.
-# Check whether --enable-lba-support-bitmap-check or --disable-lba-support-bitmap-check was given.
-if test "${enable_lba_support_bitmap_check+set}" = set; then
-  enableval="$enable_lba_support_bitmap_check"
-  :
-fi
-
-
-if test "x$enable_lba_support_bitmap_check" != xno; then
-  cat >> confdefs.h <<\EOF
-#define CHECK_LBA_SUPPORT_BITMAP 1
-EOF
-
-fi
-
 # filesystems support.
 # Check whether --enable-ext2fs or --disable-ext2fs was given.
 if test "${enable_ext2fs+set}" = set; then
diff --git a/configure.in b/configure.in
index 24c5b4d0e..9da1373e9 100644
--- a/configure.in
+++ b/configure.in
@@ -163,15 +163,6 @@ AC_CHECK_HEADERS(string.h strings.h ncurses/curses.h ncurses.h curses.h)
 
 # Check for user options.
 
-# some compile-time options.
-AC_ARG_ENABLE(lba-support-bitmap-check,
-  [  --disable-lba-support-bitmap-check
-                          disable a check for LBA support bitmap])
-
-if test "x$enable_lba_support_bitmap_check" != xno; then
-  AC_DEFINE(CHECK_LBA_SUPPORT_BITMAP)
-fi
-
 # filesystems support.
 AC_ARG_ENABLE(ext2fs,
   [  --disable-ext2fs        disable ext2fs support in Stage 2])
diff --git a/docs/grub-install.8 b/docs/grub-install.8
index 90180875e..598392c4f 100644
--- a/docs/grub-install.8
+++ b/docs/grub-install.8
@@ -20,6 +20,10 @@ instead of the root directory.
 .TP
 \fB\-\-grub\-shell\fR=\fIFILE\fR
 use FILE as the grub shell.
+.TP
+\fB\-\-force\-lba\fR
+Force GRUB to use LBA mode even for a buggy
+BIOS.
 .PP
 INSTALL_DEVICE can be a GRUB device name or a system device filename.
 .PP
diff --git a/stage1/stage1.S b/stage1/stage1.S
index 53cfb94b6..1595f3196 100644
--- a/stage1/stage1.S
+++ b/stage1/stage1.S
@@ -91,10 +91,12 @@ stage1_version:
 boot_drive:	
 	.byte 0xff	/* the disk to load stage2 from */
 			/* 0xff means use the boot drive */
-stage2_sector:
-	.long	1
+force_lba:
+	.byte	0
 stage2_address:
 	.word	0x8000
+stage2_sector:
+	.long	1
 stage2_segment:
 	.word	0x800
 
@@ -149,12 +151,15 @@ real_start:
 	cmpw	$0xaa55, %bx
 	jne	chs_mode
 
-#ifdef CHECK_LBA_SUPPORT_BITMAP
-	/* check if AH=0x42 is supported */
+	/* check if AH=0x42 is supported if FORCE_LBA is zero */
+	movb	ABS(force_lba), %al
+	testb	%al, %al
+	jnz	skip_lba_bitmap_check
 	andw	$1, %cx
 	jz	chs_mode
-#endif /* CHECK_LBA_SUPPORT_BITMAP */
-		
+	
+skip_lba_bitmap_check:
+	
 	/* get the geometry (limited to 2TB!) */
 	movb	$0x48, %ah
 	movw	$STAGE1_DRP_ADDR, %si
diff --git a/stage1/stage1.h b/stage1/stage1.h
index d38419de8..c99c0ab3b 100644
--- a/stage1/stage1.h
+++ b/stage1/stage1.h
@@ -23,7 +23,7 @@
 
 /* Define the version numbers here, so that Stage 1 can know them.  */
 #define COMPAT_VERSION_MAJOR	3
-#define COMPAT_VERSION_MINOR	0
+#define COMPAT_VERSION_MINOR	1
 #define COMPAT_VERSION		((COMPAT_VERSION_MINOR << 8) \
 					| COMPAT_VERSION_MAJOR)
 
@@ -33,21 +33,24 @@
 /* The offset of the end of BPB (BIOS Parameter Block).  */
 #define STAGE1_BPBEND		0x3e
 
-/* The offset of STAGE2_SECTOR.  */
-#define STAGE1_STAGE2_SECTOR	0x41
-
-/* The offset of STAGE2_ADDRESS.  */
-#define STAGE1_STAGE2_ADDRESS	0x45
-
-/* The offset of STAGE2_SEGMENT.  */
-#define STAGE1_STAGE2_SEGMENT	0x47
-
 /* The offset of the major version.  */
 #define STAGE1_VER_MAJ_OFFS	0x3e
 
 /* The offset of BOOT_DRIVE.  */
 #define STAGE1_BOOT_DRIVE	0x40
 
+/* The offset of FORCE_LBA.  */
+#define STAGE1_FORCE_LBA	0x41
+
+/* The offset of STAGE2_ADDRESS.  */
+#define STAGE1_STAGE2_ADDRESS	0x42
+
+/* The offset of STAGE2_SECTOR.  */
+#define STAGE1_STAGE2_SECTOR	0x44
+
+/* The offset of STAGE2_SEGMENT.  */
+#define STAGE1_STAGE2_SEGMENT	0x48
+
 /* The offset of the start of the partition table.  */
 #define STAGE1_PARTSTART	0x1be
 
diff --git a/stage2/asm.S b/stage2/asm.S
index 407f2c59b..aacd58214 100644
--- a/stage2/asm.S
+++ b/stage2/asm.S
@@ -73,6 +73,8 @@ VARIABLE(install_partition)
 	.long	0x020000
 VARIABLE(stage2_id)
 	.byte	STAGE2_ID
+VARIABLE(force_lba)
+	.byte	0
 VARIABLE(version_string)
 	.string VERSION
 VARIABLE(config_file)
diff --git a/stage2/bios.c b/stage2/bios.c
index e588da85d..dca467a82 100644
--- a/stage2/bios.c
+++ b/stage2/bios.c
@@ -163,20 +163,17 @@ get_diskinfo (int drive, struct geometry *geometry)
 		 read/write is supported, so we cannot help assuming
 		 that the functions are supported by default and
 		 clearing the flag when either of them fails. *sigh*  */
-#ifdef CHECK_LBA_SUPPORT_BITMAP
+
 	      /* Make sure that LBA read/write functions are supported.  */
-	      if (drp.flags & 1)
+	      if (force_lba || (drp.flags & 1))
 		{
-#endif
 		  geometry->flags = BIOSDISK_FLAG_LBA_EXTENSION;
 		  
 		  /* FIXME: when the 2TB limit becomes critical, we must
 		     change the type of TOTAL_SECTORS to unsigned long
 		     long.  */
 		  total_sectors = drp.total_sectors & ~0L;
-#ifdef CHECK_LBA_SUPPORT_BITMAP
 		}
-#endif
 	    }
 	}
 
diff --git a/stage2/builtins.c b/stage2/builtins.c
index e79bdc3fb..64dc482ca 100644
--- a/stage2/builtins.c
+++ b/stage2/builtins.c
@@ -1387,7 +1387,9 @@ install_func (char *arg, int flags)
   int is_stage1_5 = 0;
   /* Must call grub_close?  */
   int is_open = 0;
-
+  /* If LBA is forced?  */
+  int is_force_lba = 0;
+  
   /* Save the first sector of Stage2 in STAGE2_SECT.  */
   static void disk_read_savesect_func (int sector)
     {
@@ -1423,6 +1425,13 @@ install_func (char *arg, int flags)
       installaddr += 512;
     }
 
+  /* First, check the GNU-style long option.  */
+  if (grub_memcmp ("--force-lba", arg, 11) == 0)
+    {
+      is_force_lba = 1;
+      arg = skip_to (0, arg);
+    }
+  
   stage1_file = arg;
   dest_dev = skip_to (0, stage1_file);
   if (*dest_dev == 'd')
@@ -1486,6 +1495,8 @@ install_func (char *arg, int flags)
       goto fail;
     }
 
+  /* This below is not true any longer. But should we leave this alone?  */
+  
   /* If DEST_DRIVE is a floppy, Stage 2 must have the iteration probe
      routine.  */
   if (! (dest_drive & 0x80)
@@ -1514,8 +1525,12 @@ install_func (char *arg, int flags)
 		 " be installed on a\ndifferent drive than the drive where"
 		 " the Stage 2 resides.\n");
 
+  /* Set the boot drive.  */
   *((unsigned char *) (stage1_buffer + STAGE1_BOOT_DRIVE)) = new_drive;
 
+  /* Set the "force LBA" flag.  */
+  *((unsigned char *) (stage1_buffer + STAGE1_FORCE_LBA)) = is_force_lba;
+  
   /* Read the first sector of Stage 2.  */
   disk_read_hook = disk_read_savesect_func;
   if (grub_read (stage2_first_buffer, SECTOR_SIZE) != SECTOR_SIZE)
@@ -1594,6 +1609,10 @@ install_func (char *arg, int flags)
   while (*(config_file_location++))
     ;
 
+  /* Set the "force LBA" flag for Stage2.  */
+  *((unsigned char *) (stage2_second_buffer + STAGE2_FORCE_LBA))
+    = is_force_lba;
+  
   if (*ptr == 'p')
     {
       *((long *) (stage2_second_buffer + STAGE2_INSTALLPART))
@@ -1649,40 +1668,44 @@ install_func (char *arg, int flags)
 	  grub_strcpy (config_file_location + sizeof (device), config_file);
 	}
 
-      /* Check if the configuration filename is specified, if a Stage 1.5
-	 is used.  */
+      /* If a Stage 1.5 is used, then we need to modify the Stage2.  */
       if (is_stage1_5)
 	{
 	  char *real_config_filename = skip_to (0, ptr);
 	  
+	  is_open = grub_open (config_filename);
+	  if (! is_open)
+	    goto fail;
+
+	  /* Skip the first sector.  */
+	  grub_seek (SECTOR_SIZE);
+	  
+	  disk_read_hook = disk_read_savesect_func;
+	  if (grub_read ((char *) SCRATCHADDR, SECTOR_SIZE) != SECTOR_SIZE)
+	    goto fail;
+	  
+	  disk_read_hook = 0;
+	  grub_close ();
+	  is_open = 0;
+	  
+	  /* Sanity check.  */
+	  if (*((unsigned char *) SCRATCHADDR + STAGE2_STAGE2_ID)
+	      != STAGE2_ID_STAGE2)
+	    {
+	      errnum = ERR_BAD_VERSION;
+	      goto fail;
+	    }
+
+	  /* Set the "force LBA" flag for Stage2.  */
+	  *((unsigned char *) (SCRATCHADDR + STAGE2_FORCE_LBA))
+	    = is_force_lba;
+
+	  /* If REAL_CONFIG_FILENAME is specified, copy it to the Stage2.  */
 	  if (*real_config_filename)
 	    {
 	      /* Specified */
 	      char *location;
 	      
-	      is_open = grub_open (config_filename);
-	      if (! is_open)
-		goto fail;
-
-	      /* Skip the first sector.  */
-	      grub_seek (SECTOR_SIZE);
-	      
-	      disk_read_hook = disk_read_savesect_func;
-	      if (grub_read ((char *) SCRATCHADDR, SECTOR_SIZE) != SECTOR_SIZE)
-		goto fail;
-
-	      disk_read_hook = 0;
-	      grub_close ();
-	      is_open = 0;
-	      
-	      /* Sanity check.  */
-	      if (*((unsigned char *) SCRATCHADDR + STAGE2_STAGE2_ID)
-		  != STAGE2_ID_STAGE2)
-		{
-		  errnum = ERR_BAD_VERSION;
-		  goto fail;
-		}
-	      
 	      /* Find a string for the configuration filename.  */
 	      location = (char *) SCRATCHADDR + STAGE2_VER_STR_OFFS;
 	      while (*(location++))
@@ -1690,15 +1713,16 @@ install_func (char *arg, int flags)
 	      
 	      /* Copy the name.  */
 	      grub_strcpy (location, real_config_filename);
-	      
-	      /* Write it to the disk.  */
-	      buf_track = -1;
-	      if (biosdisk (BIOSDISK_WRITE, current_drive, &buf_geom,
-			    saved_sector, 1, SCRATCHSEG))
-		{
-		  errnum = ERR_WRITE;
-		  goto fail;
-		}
+
+	    }
+	  
+	  /* Write it to the disk.  */
+	  buf_track = -1;
+	  if (biosdisk (BIOSDISK_WRITE, current_drive, &buf_geom,
+			saved_sector, 1, SCRATCHSEG))
+	    {
+	      errnum = ERR_WRITE;
+	      goto fail;
 	    }
 	}
     }
@@ -1751,7 +1775,7 @@ static struct builtin builtin_install =
   "install",
   install_func,
   BUILTIN_CMDLINE,
-  "install STAGE1 [d] DEVICE STAGE2 [ADDR] [p] [CONFIG_FILE] [REAL_CONFIG_FILE]",
+  "install [--force-lba] STAGE1 [d] DEVICE STAGE2 [ADDR] [p] [CONFIG_FILE] [REAL_CONFIG_FILE]",
   "Install STAGE1 on DEVICE, and install a blocklist for loading STAGE2"
   " as a Stage 2. If the option `d' is present, the Stage 1 will always"
   " look for the disk where STAGE2 was installed, rather than using"
@@ -1763,6 +1787,8 @@ static struct builtin builtin_install =
   " this is the name of the true Stage 2) at boot time. If STAGE2 is a Stage"
   " 1.5 and REAL_CONFIG_FILE is present, then the Stage 2 CONFIG_FILE is"
   " patched with the configuration filename REAL_CONFIG_FILE."
+  " If the option `--force-lba' is specified, disable some sanity checks"
+  " for LBA mode."
 };
 
 
@@ -2544,6 +2570,7 @@ setup_func (char *arg, int flags)
   char cmd_arg[256];
   char device[16];
   char *buffer = (char *) RAW_ADDR (0x100000);
+  int is_force_lba = 0;
   
   static void sprint_device (int drive, int partition)
     {
@@ -2585,6 +2612,13 @@ setup_func (char *arg, int flags)
 
   tmp_drive = saved_drive;
   tmp_partition = saved_partition;
+
+  /* Check if the user specifies --force-lba.  */
+  if (grub_memcmp ("--force-lba", arg, 11) == 0)
+    {
+      is_force_lba = 1;
+      arg = skip_to (0, arg);
+    }
   
   install_ptr = arg;
   image_ptr = skip_to (0, install_ptr);
@@ -2697,7 +2731,8 @@ setup_func (char *arg, int flags)
   
 #ifdef NO_BUGGY_BIOS_IN_THE_WORLD
   /* I prefer this, but...  */
-  grub_sprintf (cmd_arg, "%s %s%s %s p %s",
+  grub_sprintf (cmd_arg, "%s%s %s%s %s p %s",
+		is_force_lba? "--force-lba " : "",
 		stage1,
 		(install_drive != image_drive) ? "d " : "",
 		device,
@@ -2708,7 +2743,8 @@ setup_func (char *arg, int flags)
      may not expect that your BIOS will pass a booting drive to stage1
      correctly. Thus, always specify the option `d', whether
      INSTALL_DRIVE is identical with IMAGE_DRIVE or not. *sigh*  */
-  grub_sprintf (cmd_arg, "%s d %s %s p %s",
+  grub_sprintf (cmd_arg, "%s%s d %s %s p %s",
+		is_force_lba? "--force-lba " : "",
 		stage1,
 		device,
 		stage2,
@@ -2738,13 +2774,14 @@ static struct builtin builtin_setup =
   "setup",
   setup_func,
   BUILTIN_CMDLINE,
-  "setup INSTALL_DEVICE [IMAGE_DEVICE]",
+  "setup [--force-lba] INSTALL_DEVICE [IMAGE_DEVICE]",
   "Set up the installation of GRUB automatically. This command uses"
   " the more flexible command \"install\" in the backend and installs"
   " GRUB into the device INSTALL_DEVICE. If IMAGE_DEVICE is specified,"
   " then find the GRUB images in the device IMAGE_DEVICE, otherwise"
   " use the current \"root device\", which can be set by the command"
-  " \"root\"."
+  " \"root\". If you know that your BIOS should support LBA but GRUB"
+  " doesn't work in LBA mode, specify the option `--force-lba'."
 };
 
 
diff --git a/stage2/shared.h b/stage2/shared.h
index 16cc33fa6..c07c7f3b3 100644
--- a/stage2/shared.h
+++ b/stage2/shared.h
@@ -192,10 +192,11 @@ extern char *grub_scratch_mem;
 
 #include <stage1.h>
 
-#define STAGE2_VER_MAJ_OFFS  0x6
-#define STAGE2_INSTALLPART   0x8
-#define STAGE2_STAGE2_ID     0xc
-#define STAGE2_VER_STR_OFFS  0xd
+#define STAGE2_VER_MAJ_OFFS	0x6
+#define STAGE2_INSTALLPART	0x8
+#define STAGE2_STAGE2_ID	0xc
+#define STAGE2_FORCE_LBA	0xd
+#define STAGE2_VER_STR_OFFS	0xe
 
 /* Stage 2 identifiers */
 #define STAGE2_ID_STAGE2		0
@@ -423,6 +424,7 @@ extern unsigned long install_partition;
 extern unsigned long boot_drive;
 extern unsigned long boot_part_addr;
 extern unsigned long boot_part_offset;
+extern unsigned char force_lba;
 extern char version_string[];
 extern char config_file[];
 
diff --git a/util/grub-install.in b/util/grub-install.in
index 6e9e0dcfd..c353514ee 100644
--- a/util/grub-install.in
+++ b/util/grub-install.in
@@ -34,6 +34,7 @@ log_file=/tmp/grub-install.log.$$
 rootdir=
 
 install_device=
+force_lba=
 debug=no
 
 # Usage: usage
@@ -48,6 +49,8 @@ Install GRUB on your drive.
   --root-directory=DIR    install GRUB images under the directory DIR
                           instead of the root directory.
   --grub-shell=FILE       use FILE as the grub shell.
+  --force-lba             Force GRUB to use LBA mode even for a buggy
+                          BIOS.
 
 INSTALL_DEVICE can be a GRUB device name or a system device filename.
 
@@ -125,6 +128,8 @@ for option; do
 	rootdir=`echo "$option" | sed 's/--root-directory=//'` ;;
     --grub-shell=*)
 	grub_shell=`echo "$option" | sed 's/--grub-shell=//'` ;;
+    --force-lba)
+	force_lba="--force-lba" ;;
     # This is an undocumented feature...
     --debug)
 	debug=yes ;;
@@ -239,7 +244,7 @@ test -x /bin/tempfile && log_file=`tempfile --prefix=grub`
 # Now perform the installation.
 $grub_shell --batch --device-map=$device_map <<EOF >$log_file
 root $root_drive
-setup $install_drive
+setup $force_lba $install_drive
 quit
 EOF