commit 08da5a2c

    x86_64: Early segment setup for VT

sets up LDT and TR into a valid state in order to speed up boot
decompression under VT.

Those code are put in code64, and it is using GDT that is only
loaded from code32 path.

That breaks booting with 64bit bootloader that does not go through
code32 path and jump to startup_64 directly, and it has different
GDT.

Move those lines into code32 after their GDT is loaded.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1359058816-7615-21-git-send-email-yinghai@kernel.org
Cc: Zachary Amsden <zamsden@gmail.com>
Cc: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

We need to move some code to 32bit section in following patch:

   x86, boot: Move lldt/ltr out of 64bit code section

but that will push startup_64 down from 0x200.

According to hpa, we can not change startup_64 position and that
is an ABI.

We could move function verify_cpu and no_longmode down, because
verify_cpu is used via function call and no_longmode will not
return, then we don't need to add extra code for jumping back.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1359058816-7615-20-git-send-email-yinghai@kernel.org
Cc: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Add an accessor function for the command line address.
Later we will add support for holding a 64-bit address via ext_cmd_line_ptr.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1359058816-7615-17-git-send-email-yinghai@kernel.org
Cc: Gokul Caushik <caushik1@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Joe Millenbach <jmillenbach@gmail.com>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Use the new sentinel field to detect bootloaders which fail to follow
protocol and don't initialize fields in struct boot_params that they
do not explicitly initialize to zero.

Based on an original patch and research by Yinghai Lu.
Changed by hpa to be invoked both in the decompression path and in the
kernel proper; the latter for the case where a bootloader takes over
decompression.
Originally-by: NYinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1359058816-7615-26-git-send-email-yinghai@kernel.orgSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

With the current code, the condition in the if() doesn't make much sense due to
precedence of operators.
Signed-off-by: NSasha Levin <sasha.levin@oracle.com>
Link: http://lkml.kernel.org/r/1356030701-16284-25-git-send-email-sasha.levin@oracle.com
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

EFI provides support for providing PCI ROMs via means other than the ROM
BAR. This support vanishes after we've exited boot services, so add support
for stashing copies of the ROMs in setup_data if they're not otherwise
available.
Signed-off-by: NMatthew Garrett <mjg@redhat.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Tested-by: NSeth Forshee <seth.forshee@canonical.com>

Building for Athlon/Duron/K7 results in the following build error,

arch/x86/boot/compressed/eboot.o: In function `__constant_memcpy3d':
eboot.c:(.text+0x385): undefined reference to `_mmx_memcpy'
arch/x86/boot/compressed/eboot.o: In function `efi_main':
eboot.c:(.text+0x1a22): undefined reference to `_mmx_memcpy'

because the boot stub code doesn't link with the kernel proper, and
therefore doesn't have access to the 3DNow version of memcpy. So,
follow the example of misc.c and #undef memcpy so that we use the
version provided by misc.c.

See https://bugzilla.kernel.org/show_bug.cgi?id=50391Reported-by: NAl Viro <viro@zeniv.linux.org.uk>
Reported-by: NRyan Underwood <nemesis@icequake.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: stable@vger.kernel.org
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>

Seth Forshee reported that his system was reporting that the EFI framebuffer
stretched from 0x90010000-0xb0010000 despite the GPU's BAR only covering
0x90000000-0x9ffffff. It's safer to calculate this value from the pixel
stride and screen height (values we already depend on) rather than face
potential problems with resource allocation later on.
Signed-off-by: NMatthew Garrett <mjg@redhat.com>
Tested-by: NSeth Forshee <seth.forshee@canonical.com>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>

The majority of the DMI checks in efifb are for cases where the bootloader
has provided invalid information. However, on some machines the overrides
may do more harm than good due to configuration differences between machines
with the same machine identifier. It turns out that it's possible for the
bootloader to get the correct information on GOP-based systems, but we
can't guarantee that the kernel's being booted with one that's been updated
to do so. Add support for a capabilities flag that can be set by the
bootloader, and skip the DMI checks in that case. Additionally, set this
flag in the UEFI stub code.
Signed-off-by: NMatthew Garrett <mjg@redhat.com>
Acked-by: NPeter Jones <pjones@redhat.com>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>

We can't assume the presence of the red zone while we're still in a boot
services environment, so we should build with -fno-red-zone to avoid
problems. Change the size of wchar at the same time to make string handling
simpler.
Signed-off-by: NMatthew Garrett <mjg@redhat.com>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>

We currently use the PCI IO protocol as a proxy for a functional GOP. This
is less than ideal, since some platforms will put the GOP on output devices
rather than the GPU itself. Move to using the conout protocol. This is not
guaranteed per-spec, but is part of the consplitter implementation that
causes this problem in the first place and so should be reliable.
Signed-off-by: NMatthew Garrett <mjg@redhat.com>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>

CONFIG_EARLY_PRINTK is the only feature that might use command line
parsing in the decompression stage.  If it is disabled then we can
exclude the related code to save space. This can result in an estimated
space savings of 2240 bytes from the compressed kernel image.
Signed-off-by: NJoe Millenbach <jmillenbach@gmail.com>
Link: http://lkml.kernel.org/r/1342746282-28497-8-git-send-email-jmillenbach@gmail.comSigned-off-by: NGokul Caushik <caushik1@gmail.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Removes early_serial_console.c code if we don't have the config option that
enables it (EARLY_PRINTK). When disabling this code, make early_serial_base a
constant 0 to allow the compiler to optimize away the code that checks for
early_serial_base.
Signed-off-by: NJoe Millenbach <jmillenbach@gmail.com>
Link: http://lkml.kernel.org/r/1342746282-28497-7-git-send-email-jmillenbach@gmail.comSigned-off-by: NGokul Caushik <caushik1@gmail.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

As we're no longer using the flag we don't need to extract the value from the
command line and store it. This is a step towards removing command line
parameter code.
Signed-off-by: NJoe Millenbach <jmillenbach@gmail.com>
Link: http://lkml.kernel.org/r/1342746282-28497-6-git-send-email-jmillenbach@gmail.comSigned-off-by: NGokul Caushik <caushik1@gmail.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Changed putstr flagging from parameter to conditional compilation for puts,
debug_putstr, and error_putstr. This allows for space savings since most
configurations won't use this feature.
Signed-off-by: NJoe Millenbach <jmillenbach@gmail.com>
Link: http://lkml.kernel.org/r/1342746282-28497-5-git-send-email-jmillenbach@gmail.comSigned-off-by: NGokul Caushik <caushik1@gmail.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

For consistency we changed the error output path to match the new debug path.
Signed-off-by: NJoe Millenbach <jmillenbach@gmail.com>
Link: http://lkml.kernel.org/r/1342746282-28497-4-git-send-email-jmillenbach@gmail.comSigned-off-by: NGokul Caushik <caushik1@gmail.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Change all instances of if (debug) putstr(...) to a new debug_putstr(...).
This allows a future change to conditionally stub out debug_putstr to save
space.
Signed-off-by: NJoe Millenbach <jmillenbach@gmail.com>
Link: http://lkml.kernel.org/r/1342746282-28497-3-git-send-email-jmillenbach@gmail.comSigned-off-by: NGokul Caushik <caushik1@gmail.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

There are only 3 uses of the quiet flag and they all protect output that
is only useful for debugging the stub, therefore we switched to using the
debug flag for all extra output.
Signed-off-by: NJoe Millenbach <jmillenbach@gmail.com>
Link: http://lkml.kernel.org/r/1342746282-28497-2-git-send-email-jmillenbach@gmail.comSigned-off-by: NGokul Caushik <caushik1@gmail.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

As things currently stand, traditional EFI boot loaders and the EFI
boot stub are carrying essentially the same initialisation code
required to setup an EFI machine for booting a kernel. There's really
no need to have this code in two places and the hope is that, with
this new protocol, initialisation and booting of the kernel can be
left solely to the kernel's EFI boot stub. The responsibilities of the
boot loader then become,

   o Loading the kernel image from boot media

File system code still needs to be carried by boot loaders for the
scenario where the kernel and initrd files reside on a file system
that the EFI firmware doesn't natively understand, such as ext4, etc.

   o Providing a user interface

Boot loaders still need to display any menus/interfaces, for example
to allow the user to select from a list of kernels.

Bump the boot protocol number because we added the 'handover_offset'
field to indicate the location of the handover protocol entry point.

Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Jones <pjones@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
Acked-and-Tested-by: NMatthew Garrett <mjg@redhat.com>
Link: http://lkml.kernel.org/r/1342689828-16815-1-git-send-email-matt@console-pimps.orgSigned-off-by: NH. Peter Anvin <hpa@zytor.com>

We need a way of printing useful messages to the user, for example
when we fail to open an initrd file, instead of just hanging the
machine without giving the user any indication of what went wrong. So
sprinkle some error messages throughout the EFI boot stub code to make
it easier for users to diagnose/report problems.
Reported-by: NKeshav P R <the.ridikulus.rat@gmail.com>
Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1331907517-3985-3-git-send-email-matt@console-pimps.orgSigned-off-by: NH. Peter Anvin <hpa@zytor.com>

The loop at the 'close_handles' label in handle_ramdisks() should be
using 'i', which represents the number of initrd files that were
successfully opened, not 'nr_initrds' which is the number of initrd=
arguments passed on the command line.

Currently, if we execute the loop to close all file handles and we
failed to open any initrds we'll try to call the close function on a
garbage pointer, causing the machine to hang.

Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1331907517-3985-2-git-send-email-matt@console-pimps.orgSigned-off-by: NH. Peter Anvin <hpa@zytor.com>

A new option is added to the relocs tool called '--realmode'.
This option causes the generation of 16-bit segment relocations
and 32-bit linear relocations for the real-mode code. When
the real-mode code is moved to the low-memory during kernel
initialization, these relocation entries can be used to
relocate the code properly.

In the assembly code 16-bit segment relocations must be relative
to the 'real_mode_seg' absolute symbol. Linear relocations must be
relative to a symbol prefixed with 'pa_'.

16-bit segment relocation is used to load cs:ip in 16-bit code.
Linear relocations are used in the 32-bit code for relocatable
data references. They are declared in the linker script of the
real-mode code.

The relocs tool is moved to arch/x86/tools/relocs.c, and added new
target archscripts that can be used to build scripts needed building
an architecture.  be compiled before building the arch/x86 tree.

[ hpa: accelerating this because it detects invalid absolute
  relocations, a serious bug in binutils 2.22.52.0.x which currently
  produces bad kernels. ]
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1336501366-28617-2-git-send-email-jarkko.sakkinen@intel.comSigned-off-by: NJarkko Sakkinen <jarkko.sakkinen@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@vger.kernel.org>

Moved relocs tool from scripts/ to arch/x86/tools because
it is architecture specific script. Added new target archscripts
that can be used to build scripts needed building an architecture.
Signed-off-by: NJarkko Sakkinen <jarkko.sakkinen@intel.com>
Link: http://lkml.kernel.org/r/1336501366-28617-22-git-send-email-jarkko.sakkinen@intel.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Michal Marek <mmarek@suse.cz>

A new option is added to the relocs tool called '--realmode'.
This option causes the generation of 16-bit segment relocations
and 32-bit linear relocations for the real-mode code. When
the real-mode code is moved to the low-memory during kernel
initialization, these relocation entries can be used to
relocate the code properly.

In the assembly code 16-bit segment relocations must be relative
to the 'real_mode_seg' absolute symbol. Linear relocations must be
relative to a symbol prefixed with 'pa_'.

16-bit segment relocation is used to load cs:ip in 16-bit code.
Linear relocations are used in the 32-bit code for relocatable
data references. They are declared in the linker script of the
real-mode code.

The relocs tool is moved to scripts/x86-relocs.c so it will
be compiled before building the arch/x86 tree.
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1336501366-28617-2-git-send-email-jarkko.sakkinen@intel.comSigned-off-by: NJarkko Sakkinen <jarkko.sakkinen@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

sh_symtab is set but not used.

[ hpa: putting this in urgent because of the sheer harmlessness of the patch:
  it quiets a build warning but does not change any generated code. ]
Signed-off-by: NKusanagi Kouichi <slash@ac.auone-net.jp>
Link: http://lkml.kernel.org/r/20120401082932.D5E066FC03D@msa105.auone-net.jpSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@vger.kernel.org>

sh_symtab is set but not used.
Signed-off-by: NKusanagi Kouichi <slash@ac.auone-net.jp>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

The method used to work out whether we were booted by EFI firmware or
via a boot loader is broken. Because efi_main() is always executed
when booting from a boot loader we will dereference invalid pointers
either on the stack (CONFIG_X86_32) or contained in %rdx
(CONFIG_X86_64) when searching for an EFI System Table signature.

Instead of dereferencing these invalid system table pointers, add a
new entry point that is only used when booting from EFI firmware, when
we know the pointer arguments will be valid. With this change legacy
boot loaders will no longer execute efi_main(), but will instead skip
EFI stub initialisation completely.

[ hpa: Marking this for urgent/stable since it is a regression when
  the option is enabled; without the option the patch has no effect ]
Signed-off-by: NMatt Fleming <matt.hfleming@intel.com>
Link: http://lkml.kernel.org/r/1334584744.26997.14.camel@mfleming-mobl1.ger.corp.intel.comReported-by: NJordan Justen <jordan.l.justen@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@vger.kernel.org> v3.3

This change modifes the PE .text section to start after
the first sector of the kernel image.

The header may be modified by the UEFI secure boot signing,
so it is not appropriate for it to be included in one of the
image sections. Since the sections are part of the secure
boot hash, this modification to the .text section contents
would invalidate the secure boot signed hash.

Note: UEFI secure boot does hash the image header, but
fields that are changed by the signing process are excluded
from the hash calculation.  This exclusion process is only
handled for the image header, and not image sections.

Luckily, we can still easily boot without the first sector
by initializing a few fields in arch/x86/boot/compressed/eboot.c.
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1332520506-6472-3-git-send-email-jordan.l.justen@intel.com
[jordan.l.justen@intel.com: set .text vma & file offset]
Signed-off-by: NJordan Justen <jordan.l.justen@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

"filename" is a efi_char16_t string so this check for reaching the end
of the array doesn't work.  We need to cast the pointer to (u8 *) before
doing the math.

This patch changes the "filename" to "filename_16" to avoid confusion in
the future.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Link: http://lkml.kernel.org/r/20120305180614.GA26880@elgon.mountainAcked-by: NMatt Fleming <matt.fleming@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Use the new headers in tools/include instead of rolling our own
put_unaligned_le32() implementation.

Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1330436245-24875-4-git-send-email-matt@console-pimps.orgSigned-off-by: NH. Peter Anvin <hpa@zytor.com>

Use the new headers in tools/include instead of rolling our own
put_unaligned_le32() implementation.

Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1330436245-24875-3-git-send-email-matt@console-pimps.orgSigned-off-by: NH. Peter Anvin <hpa@zytor.com>

We allocate memory with malloc(), but neglect to free it before
the variable 'phdrs' goes out of scope --> leak.
Signed-off-by: NJesper Juhl <jj@chaosbits.net>
Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1201232332590.8772@swampdragon.chaosbits.net
[ Mostly harmless. ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The efi boot stub tries to read the entire initrd in 1 go, however
some efi implementations hang if too much if asked to read too much
data at the same time. After some experimentation I found out that my
asrock p67 board will hang if asked to read chunks of 4MiB, so use a
safe value.

elilo reads in chunks of 16KiB, but since that requires many read
calls I use a value of 1 MiB.  hpa suggested adding individual
blacklists for when systems are found where this value causes a crash.
Signed-off-by: NMaarten Lankhorst <m.b.lankhorst@gmail.com>
Link: http://lkml.kernel.org/r/4EEB3A02.3090201@gmail.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

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>

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>

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>