There is currently a large divide between kernel development and the
development of EFI boot loaders. The idea behind this patch is to give
the kernel developers full control over the EFI boot process. As
H. Peter Anvin put it,

"The 'kernel carries its own stub' approach been very successful in
dealing with BIOS, and would make a lot of sense to me for EFI as
well."

This patch introduces an EFI boot stub that allows an x86 bzImage to
be loaded and executed by EFI firmware. The bzImage appears to the
firmware as an EFI application. Luckily there are enough free bits
within the bzImage header so that it can masquerade as an EFI
application, thereby coercing the EFI firmware into loading it and
jumping to its entry point. The beauty of this masquerading approach
is that both BIOS and EFI boot loaders can still load and run the same
bzImage, thereby allowing a single kernel image to work in any boot
environment.

The EFI boot stub supports multiple initrds, but they must exist on
the same partition as the bzImage. Command-line arguments for the
kernel can be appended after the bzImage name when run from the EFI
shell, e.g.

Shell> bzImage console=ttyS0 root=/dev/sdb initrd=initrd.img

v7:
 - Fix checkpatch warnings.

v6:

 - Try to allocate initrd memory just below hdr->inird_addr_max.

v5:

 - load_options_size is UTF-16, which needs dividing by 2 to convert
   to the corresponding ASCII size.

v4:

 - Don't read more than image->load_options_size

v3:

 - Fix following warnings when compiling CONFIG_EFI_STUB=n

   arch/x86/boot/tools/build.c: In function ‘main’:
   arch/x86/boot/tools/build.c:138:24: warning: unused variable ‘pe_header’
   arch/x86/boot/tools/build.c:138:15: warning: unused variable ‘file_sz’

 - As reported by Matthew Garrett, some Apple machines have GOPs that
   don't have hardware attached. We need to weed these out by
   searching for ones that handle the PCIIO protocol.

 - Don't allocate memory if no initrds are on cmdline
 - Don't trust image->load_options_size

Maarten Lankhorst noted:
 - Don't strip first argument when booted from efibootmgr
 - Don't allocate too much memory for cmdline
 - Don't update cmdline_size, the kernel considers it read-only
 - Don't accept '\n' for initrd names

v2:

 - File alignment was too large, was 8192 should be 512. Reported by
   Maarten Lankhorst on LKML.
 - Added UGA support for graphics
 - Use VIDEO_TYPE_EFI instead of hard-coded number.
 - Move linelength assignment until after we've assigned depth
 - Dynamically fill out AddressOfEntryPoint in tools/build.c
 - Don't use magic number for GDT/TSS stuff. Requested by Andi Kleen
 - The bzImage may need to be relocated as it may have been loaded at
   a high address address by the firmware. This was required to get my
   macbook booting because the firmware loaded it at 0x7cxxxxxx, which
   triggers this error in decompress_kernel(),

	if (heap > ((-__PAGE_OFFSET-(128<<20)-1) & 0x7fffffff))
		error("Destination address too large");

Cc: Mike Waychison <mikew@google.com>
Cc: Matthew Garrett <mjg@redhat.com>
Tested-by: NHenrik Rydberg <rydberg@euromail.se>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1321383097.2657.9.camel@mfleming-mobl1.ger.corp.intel.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

There are numerous broken references to Documentation files (in other
Documentation files, in comments, etc.). These broken references are
caused by typo's in the references, and by renames or removals of the
Documentation files. Some broken references are simply odd.

Fix these broken references, sometimes by dropping the irrelevant text
they were part of.
Signed-off-by: NPaul Bolle <pebolle@tiscali.nl>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

This has been obsoleted by the root= commandline and the rdev utility
for many, many years.  People who still depend on this will surely
have a copy of the rdev utility around, the rest of the world gets rid
of another piece of buildhost-dependent data in the build. Thanks to
Paul Bolle for the build.c cleanup.

Cc: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: NMichal Marek <mmarek@suse.cz>
Link: http://lkml.kernel.org/r/1302607824-24699-1-git-send-email-mmarek@suse.czSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

When we use BIOS function e801 to probe memory, we should use ax/bx
(or cx/dx) as a pair, not mix and match.  This was a typo during the
translation from assembly code, and breaks at least one set of
machines in the field (which return cx = dx = 0).
Reported-and-tested-by: NChris Samuel <chris@csamuel.org>
Fix-proposed-by: NThomas Meyer <thomas@m3y3r.de>
Link: http://lkml.kernel.org/r/1303566747.12067.10.camel@localhost.localdomain

Ensure build doesn't silently continue despite read failure,
addressing a warning due to the unchecked call.
Signed-off-by: NDaniel J Blueman <daniel.blueman@gmail.com>
LKML-Reference: <AANLkTimxxTMU3=4ry-_zbY6v1xiDi+hW9y1RegTr8vLK@mail.gmail.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

This integrates the XZ decompression code to the x86 pre-boot code.

mkpiggy.c is updated to reserve about 32 KiB more buffer safety margin for
kernel decompression.  It is done unconditionally for all decompressors to
keep the code simpler.

The XZ decompressor needs around 30 KiB of heap, so the heap size is
increased to 32 KiB on both x86-32 and x86-64.

Documentation/x86/boot.txt is updated to list the XZ magic number.

With the x86 BCJ filter in XZ, XZ-compressed x86 kernel tends to be a few
percent smaller than the equivalent LZMA-compressed kernel.
Signed-off-by: NLasse Collin <lasse.collin@tukaani.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alain Knaff <alain@knaff.lu>
Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Cc: Phillip Lougher <phillip@lougher.demon.co.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A relocatable kernel can be anywhere in lowmem -- and in the case of a
kdump kernel, is likely to be fairly high.  Since the early page
tables map everything from address zero up we need to make sure we
allocate enough brk that we can map all of lowmem if we need to.
Reported-by: NStanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Tested-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <4D0AD3ED.8070607@kernel.org>

The code is 32bit already, and can be used in 32bit routines.
Signed-off-by: NKees Cook <kees.cook@canonical.com>
LKML-Reference: <1289414154-7829-2-git-send-email-kees.cook@canonical.com>
Acked-by: NPekka Enberg <penberg@kernel.org>
Acked-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

The kernel decompression code parses the ELF header and then copies
the segment to the corresponding destination.  Currently it uses slow
byte-copy code.  This patch makes it use the string copy operations
instead.

In the test the copy performance can be improved very significantly after using
the string copy operation mechanism.
        1. The copy time can be reduced from 150ms to 20ms on one Atom machine
	2. The copy time can be reduced about 80% on another machine
		The time is reduced from 7ms to 1.5ms when using 32-bit kernel.
		The time is reduced from 10ms to 2ms when using 64-bit kernel.
Signed-off-by: NZhao Yakui <yakui.zhao@intel.com>
LKML-Reference: <1286502453-7043-1-git-send-email-yakui.zhao@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

earlyprintk can take and I/O port, so we need to handle this case in
the setup code too, otherwise 0x3f8 will be treated as a baud rate.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <4C7B05A6.4010801@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Torsten reported that there is garbage output,
after commit 8fee13a4 (x86,
setup: enable early console output from the decompressor)

It turns out we missed the offset for that case.
Reported-by: NTorsten Kaiser <just.for.lkml@googlemail.com>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <4C7B0578.8090807@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

It is a subset of <ctype.h> functionality, so name it ctype.h.  Also,
reorganize header files so #include statements are clustered near the
top as they should be.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
LKML-Reference: <4C5752F2.8030206@kernel.org>

This enables the decompressor output to be seen on the serial console.
Most of the code is shared with the regular boot code.

We could add printf to the decompressor if needed, but currently there
is no sufficiently compelling user.

-v2: define BOOT_BOOT_H to avoid include boot.h
-v3: early_serial_base need to be static in misc.c ?
-v4: create seperate string.c printf.c cmdline.c early_serial_console.c
     after hpa's patch that allow global variables in compressed/misc stage
-v5: remove printf.c related
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Separate early_serial_console from tty.c

This allows for reuse of
early_serial_console.c/string.c/printf.c/cmdline.c in boot/compressed/.

-v2: according to hpa, don't include string.c etc
-v3: compressed/misc.c must have early_serial_base as static, so move it back to tty.c
     for setup code
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <4C568D2B.205@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

In order for global variables and functions to work in the
decompressor, we need to fix up the GOT in assembly code.
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
LKML-Reference: <4C57382E.8050501@zytor.com>

putchar is using early_serial_base to check if port is initialized.

So we only assign it after early_serial_init() is called,
in case we need use VGA to debug early serial console.

Also add display for port addr and baud.

-v2: update to current tip
Acked-by: NPekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <4C3E0171.6050008@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Make the boot code also accept the console=uart8250,io,0x2f8,115200n
form of early console.

Also add back simple_guess_base(), otherwise those simple_strtoull(,,0)
are not going to work.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <4C3CCE05.4090505@kernel.org>
Acked-by: NPekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

This patch adds serial I/O support to the real-mode setup (very early
boot) printf(). It's useful for debugging boot code when running Linux
under KVM, for example. The actual code was lifted from early printk.

Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: NPekka Enberg <penberg@cs.helsinki.fi>
LKML-Reference: <1278835617-11368-1-git-send-email-penberg@cs.helsinki.fi>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Catch missing conversion to the register structure "glove box" scheme.

Found by gcc 4.6's new warnings.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
LKML-Reference: <20100610111040.F1781B1A2B@basil.firstfloor.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

This reverts commit b3b77c8c, which was
also totally broken (see commit 0d2daf5c that reverted the crc32
version of it).  As reported by Stephen Rothwell, it causes problems on
big-endian machines:

> In file included from fs/jfs/jfs_types.h:33,
>                  from fs/jfs/jfs_incore.h:26,
>                  from fs/jfs/file.c:22:
> fs/jfs/endian24.h:36:101: warning: "__LITTLE_ENDIAN" is not defined

The kernel has never had that crazy "__BYTE_ORDER == __LITTLE_ENDIAN"
model.  It's not how we do things, and it isn't how we _should_ do
things.  So don't go there.
Requested-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Linux does not define __BYTE_ORDER in its endian header files which makes
some header files bend backwards to get at the current endian.  Lets
#define __BYTE_ORDER in big_endian.h/litte_endian.h to make it easier for
header files that are used in user space too.

In userspace the convention is that

  1. _both_ __LITTLE_ENDIAN and __BIG_ENDIAN are defined,
  2. you have to test for e.g. __BYTE_ORDER == __BIG_ENDIAN.
Signed-off-by: NJoakim Tjernlund <Joakim.Tjernlund@transmode.se>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NDenys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

The code for setting standard VGA modes probes for the current mode,
and skips the mode setting if the mode is 3 (color text 80x25) or 7
(mono text 80x25).  Unfortunately, there are BIOSes, including the
VMware BIOS, which report the previous mode if function 0F is queried
while the screen is in a VESA mode, and of course, nothing can help a
mode poked directly into the hardware.

As such, the safe option is to set the mode anyway, and only query to
see if we should be using mode 7 rather than mode 3.  People who don't
want any mode setting at all should probably use vga=0x0f04
(VIDEO_CURRENT_MODE).  It's possible that should be the kernel
default.

Reported-by Rene Arends <R.R.Arends@hro.nl>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
LKML-Reference: <tip-*@git.kernel.org>

Inhibit output from the kernel decompressor if the video information
is invalid.  This was already the case for 32 bits, make 64 bits
match.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
LKML-Reference: <tip-*@git.kernel.org>

When we restore the screen content after a mode change, we return the
cursor to its former position.  However, we need to also update
boot_params.screen_info accordingly, so that the decompression code
knows where on the screen the cursor is.  Just in case the video BIOS
does something extra screwy, read the cursor position back from the
BIOS instead of relying on it doing the right thing.

While we're at it, make sure we cap the cursor position to the new
screen coordinates.
Reported-by: NWim Osterholt <wim@djo.tudelft.nl>
Bugzilla-Reference: http://bugzilla.kernel.org/show_bug.cgi?id=15329Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Signed-off-by: NFrans Pop <elendil@planet.nl>
Cc: Avi Kivity <avi@redhat.com>
Cc: x86@kernel.org
LKML-Reference: <1265478443-31072-10-git-send-email-elendil@planet.nl>
[ Left out the KVM bits. ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Iomem has no special significance on x86.  Use the standard mem*
functions instead of trying to call other versions.  Some fixups
are needed to match the function prototypes.
Signed-off-by: NBrian Gerst <brgerst@gmail.com>
LKML-Reference: <1265380629-3212-6-git-send-email-brgerst@gmail.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

The necessary changes to the x86 Kconfig and boot/compressed to allow the
use of this new compression method
Signed-off-by: NAlbin Tonnerre <albin.tonnerre@free-electrons.com>
Acked-by: NH. Peter Anvin <hpa@zytor.com>
Tested-by: NWu Zhangjin <wuzhangjin@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Tested-by: NRussell King <rmk@arm.linux.org.uk>
Acked-by: NRussell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Recently, some distros have started shipping versions of gcc which
default to -march=i686.  This breaks building kernels for pre-i686
machines, even if they have been selected in Kconfig, due to the
generation of CMOV instructions.

There isn't enough benefit to try to preserve the generation of these
instructions even when selected, so simply force -march=i386 for the
decompressor when building a 32-bit kernel.
Reported-and-tested-by: NChris Rankin <rankincj@yahoo.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
LKML-Reference: <219280.97558.qm@web52907.mail.re2.yahoo.com>

This adds a new category of symbols to the relocs program: symbols
which are known to be relative, even though the linker emits them as
absolute; this is the case for symbols that live in the linker script,
which currently applies to _end.

Unfortunately the previous workaround of putting _end in its own empty
section was defeated by newer binutils, which remove empty sections
completely.

This patch also changes the symbol matching to use regular expressions
instead of hardcoded C for specific patterns.

This is a decidedly non-minimal patch: a modified version of the
relocs program is used as part of the Syslinux build, and this 	is
basically a backport to Linux of some of those changes; they have
thus been well tested.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
LKML-Reference: <4AF86211.3070103@zytor.com>
Acked-by: NMichal Marek <mmarek@suse.cz>
Tested-by: NSedat Dilek <sedat.dilek@gmail.com>

Fix up all users of utsrelease.h
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

Rather than having X86_L1_CACHE_BYTES and X86_L1_CACHE_SHIFT
(with inconsistent defaults), just having the latter suffices as
the former can be easily calculated from it.

To be consistent, also change X86_INTERNODE_CACHE_BYTES to
X86_INTERNODE_CACHE_SHIFT, and set it to 7 (128 bytes) for NUMA
to account for last level cache line size (which here matters
more than L1 cache line size).

Finally, make sure the default value for X86_L1_CACHE_SHIFT,
when X86_GENERIC is selected, is being seen before that for the
individual CPU model options (other than on x86-64, where
GENERIC_CPU is part of the choice construct, X86_GENERIC is a
separate option on ix86).
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Acked-by: NRavikiran Thirumalai <kiran@scalex86.org>
Acked-by: NNick Piggin <npiggin@suse.de>
LKML-Reference: <4AFD5710020000780001F8F0@vpn.id2.novell.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Add a field to store the boot cursor state and implement this for VGA on
x86. This can then be used to set the default policy for the boot console.
Signed-off-by: NMatthew Garrett <mjg@redhat.com>
LKML-Reference: <1258142222-16092-1-git-send-email-mjg@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

A single 'movl' is shorter than the 'xorl'-'orl' pair.
No change in behaviour.
Signed-off-by: NAlexander Potashev <aspotashev@gmail.com>
LKML-Reference: <1256341043-4928-1-git-send-email-aspotashev@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Older binutils breaks if ASSERT() is used without a sink
for the output.

For example 2.14.90.0.6 is known to be broken, the link
fails with:

  LD      .tmp_vmlinux1
  ld:arch/x86/kernel/vmlinux.lds:678: parse error

Document this quirk in all three files that use it.

  See:    http://marc.info/?l=linux-kbuild&m=124930110427870&w=2
  See[2]: d2ba8b21 ("x86: Fix assert syntax in vmlinux.lds.S")

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Roland McGrath <roland@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
LKML-Reference: <4AD6523D.5030909@zytor.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Replace the use of CROSS_COMPILE to select a customized
installkernel script with the possibility to set INSTALLKERNEL
to select a custom installkernel script when running make:

    make INSTALLKERNEL=arm-installkernel install

With this patch we are now more consistent across
different architectures - they did not all support use
of CROSS_COMPILE.

The use of CROSS_COMPILE was a hack as this really belongs
to gcc/binutils and the installkernel script does not change
just because we change toolchain.

The use of CROSS_COMPILE caused troubles with an upcoming patch
that saves CROSS_COMPILE when a kernel is built - it would no
longer be installable.
[Thanks to Peter Z. for this hint]

This patch undos what Ian did in commit:

  0f8e2d62
  ("use ${CROSS_COMPILE}installkernel in arch/*/boot/install.sh")

The patch has been lightly tested on x86 only - but all changes
looks obvious.
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Acked-by: Mike Frysinger <vapier@gentoo.org> [blackfin]
Acked-by: Russell King <linux@arm.linux.org.uk> [arm]
Acked-by: Paul Mundt <lethal@linux-sh.org> [sh]
Acked-by: "H. Peter Anvin" <hpa@zytor.com> [x86]
Cc: Ian Campbell <icampbell@arcom.com>
Cc: Tony Luck <tony.luck@intel.com> [ia64]
Cc: Fenghua Yu <fenghua.yu@intel.com> [ia64]
Cc: Hirokazu Takata <takata@linux-m32r.org> [m32r]
Cc: Geert Uytterhoeven <geert@linux-m68k.org> [m68k]
Cc: Kyle McMartin <kyle@mcmartin.ca> [parisc]
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> [powerpc]
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> [s390]
Cc: Thomas Gleixner <tglx@linutronix.de> [x86]
Cc: Ingo Molnar <mingo@redhat.com> [x86]
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>

This has the consequence of changing the section name use for head
code from ".text.head" to ".head.text".

Linus suggested that we merge the ".text.head" section with ".text"
(presumably while preserving the fact that the head code starts at 0).
When I tried this it caused the kernel to not boot.
Signed-off-by: NTim Abbott <tabbott@ksplice.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

The absence of vmlinux.lds here keeps .vmlinux.lds.cmd from being
included, which in turn leads to it and all its dependents always
getting rebuilt independent of whether they are already up-to-date.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
LKML-Reference: <4A8D84670200007800010D31@vpn.id2.novell.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Some intcall() misuses the input biosregs as output in
cf06de7b

This fixes the problem vga=ask boot option doesn't show enough modes.
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
LKML-Reference: <20090701021307.GA3127@localhost.localdomain>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>