Commit Graph

63 Commits

Author SHA1 Message Date
Florian Fainelli e08b187745 initramfs: fix initramfs rebuilds w/ compression after disabling
This is a follow-up to commit 57ddfdaa9a ("initramfs: fix disabling of
initramfs (and its compression)").  This particular commit fixed the use
case where we build the kernel with an initramfs with no compression,
and then we build the kernel with no initramfs.

Now this still left us with the same case as described here:

  http://lkml.kernel.org/r/20170521033337.6197-1-f.fainelli@gmail.com

not working with initramfs compression.  This can be seen by the
following steps/timestamps:

  https://www.spinics.net/lists/kernel/msg2598153.html

.initramfs_data.cpio.gz.cmd is correct:

  cmd_usr/initramfs_data.cpio.gz := /bin/bash
  ./scripts/gen_initramfs_list.sh -o usr/initramfs_data.cpio.gz  -u 1000 -g 1000  /home/fainelli/work/uclinux-rootfs/romfs /home/fainelli/work/uclinux-rootfs/misc/initramfs.dev

and was generated the first time we did generate the gzip initramfs, so
the command has not changed, nor its arguments, so we just don't call
it, no initramfs cpio is re-generated as a consequence.

The fix for this problem is just to properly keep track of the
.initramfs_cpio_data.d file by suffixing it with the compression
extension.  This takes care of properly tracking dependencies such that
the initramfs get (re)generated any time files are added/deleted etc.

Link: http://lkml.kernel.org/r/20170930033936.6722-1-f.fainelli@gmail.com
Fixes: db2aa7fd15 ("initramfs: allow again choice of the embedded initramfs compression algorithm")
Fixes: 9e3596b0c6 ("kbuild: initramfs cleanup, set target from Kconfig")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: "Francisco Blas Izquierdo Riera (klondike)" <klondike@xiscosoft.net>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-03 07:39:19 -07:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Rob Landley f2e8954b0d ramfs: clarify help text that compression applies to ramfs as well as legacy ramdisk.
Clarify help text that compression applies to ramfs as well as legacy ramdisk.

Link: http://lkml.kernel.org/r/f206a960-5a61-cf59-f27c-e9f34872063c@landley.net
Signed-off-by: Rob Landley <rob@landley.net>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:30 -07:00
Rob Landley 595a22acee scripts/gen_initramfs_list.sh: teach INITRAMFS_ROOT_UID and INITRAMFS_ROOT_GID that -1 means "current user".
Teach INITRAMFS_ROOT_UID and INITRAMFS_ROOT_GID that -1 means "current user".

Link: http://lkml.kernel.org/r/2df3a9fb-4378-fa16-679d-99e788926c05@landley.net
Signed-off-by: Rob Landley <rob@landley.net>
Cc: Michal Marek <mmarek@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:29 -07:00
Florian Fainelli 57ddfdaa9a initramfs: fix disabling of initramfs (and its compression)
Commit db2aa7fd15 ("initramfs: allow again choice of the embedded
initram compression algorithm") introduced the possibility to select the
initramfs compression algorithm from Kconfig and while this is a nice
feature it broke the use case described below.

Here is what my build system does:

 - kernel is initially configured not to have an initramfs included

 - build the user space root file system

 - re-configure the kernel to have an initramfs included
   (CONFIG_INITRAMFS_SOURCE="/path/to/romfs") and set relevant
   CONFIG_INITRAMFS options, in my case, no compression option
   (CONFIG_INITRAMFS_COMPRESSION_NONE)

 - kernel is re-built with these options -> kernel+initramfs image is
   copied

 - kernel is re-built again without these options -> kernel image is
   copied

Building a kernel without an initramfs means setting this option:

  CONFIG_INITRAMFS_SOURCE="" (and this one only)

whereas building a kernel with an initramfs means setting these options:

  CONFIG_INITRAMFS_SOURCE="/home/fainelli/work/uclinux-rootfs/romfs /home/fainelli/work/uclinux-rootfs/misc/initramfs.dev"
  CONFIG_INITRAMFS_ROOT_UID=1000
  CONFIG_INITRAMFS_ROOT_GID=1000
  CONFIG_INITRAMFS_COMPRESSION_NONE=y
  CONFIG_INITRAMFS_COMPRESSION=""

Commit db2aa7fd15 ("initramfs: allow again choice of the embedded
initram compression algorithm") is problematic because
CONFIG_INITRAMFS_COMPRESSION which is used to determine the
initramfs_data.cpio extension/compression is a string, and due to how
Kconfig works it will evaluate in order, how to assign it.

Setting CONFIG_INITRAMFS_COMPRESSION_NONE with CONFIG_INITRAMFS_SOURCE=""
cannot possibly work (because of the depends on INITRAMFS_SOURCE!=""
imposed on CONFIG_INITRAMFS_COMPRESSION ) yet we still get
CONFIG_INITRAMFS_COMPRESSION assigned to ".gz" because CONFIG_RD_GZIP=y
is set in my kernel, even when there is no initramfs being built.

So we basically end-up generating two initramfs_data.cpio* files, one
without extension, and one with .gz.  This causes usr/Makefile to track
usr/initramfs_data.cpio.gz, and not usr/initramfs_data.cpio anymore,
that is also largely problematic after 9e3596b0c6 ("kbuild:
initramfs cleanup, set target from Kconfig") because we used to track
all possible initramfs_data files in the $(targets) variable before that
commit.

The end result is that the kernel with an initramfs clearly does not
contain what we expect it to, it has a stale initramfs_data.cpio file
built into it, and we keep re-generating an initramfs_data.cpio.gz file
which is not the one that we want to include in the kernel image proper.

The fix consists in hiding CONFIG_INITRAMFS_COMPRESSION when
CONFIG_INITRAMFS_SOURCE="".  This puts us back in a state to the
pre-4.10 behavior where we can properly disable and re-enable initramfs
within the same kernel .config file, and be in control of what
CONFIG_INITRAMFS_COMPRESSION is set to.

Fixes: db2aa7fd15 ("initramfs: allow again choice of the embedded initram compression algorithm")
Fixes: 9e3596b0c6 ("kbuild: initramfs cleanup, set target from Kconfig")
Link: http://lkml.kernel.org/r/20170521033337.6197-1-f.fainelli@gmail.com
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Cc: P J P <ppandit@redhat.com>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-06-02 15:07:37 -07:00
Daniel Thompson cff75e0b6f initramfs: provide a way to ignore image provided by bootloader
Many "embedded" architectures provide CMDLINE_FORCE to allow the kernel
to override the command line provided by an inflexible bootloader.
However there is currrently no way for the kernel to override the
initramfs image provided by the bootloader meaning there are still ways
for bootloaders to make things difficult for us.

Fix this by introducing INITRAMFS_FORCE which can prevent the kernel
from loading the bootloader supplied image.

We use CMDLINE_FORCE (and its friend CMDLINE_EXTEND) to imply that the
system has an inflexible bootloader.  This allow us to avoid presenting
this config option to users of systems where inflexible bootloaders
aren't usually a problem.

Link: http://lkml.kernel.org/r/20170217121940.30126-1-daniel.thompson@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08 17:15:12 -07:00
Nicholas Piggin 9e3596b0c6 kbuild: initramfs cleanup, set target from Kconfig
Rather than keep a list of all possible compression types in the
Makefile, set the target explicitly from Kconfig.

Reviewed-by: Francisco Blas Izquierdo Riera (klondike) <klondike@klondike.es>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-01-05 09:40:16 -08:00
Nicholas Piggin ae30ab4cd7 kbuild: initramfs fix dependency checking for compressed target
When using initramfs compression, the data file compression suffix
gets quotes pulled in from Kconfig, e.g., initramfs_data.cpio".gz"
which make does not match a target and causes rebuild.

Fix this by filtering out quotes from the Kconfig string.

Fixes: 35e669e1a2 ("initramfs: select builtin initram compression algorithm on KConfig instead of Makefile")
Reviewed-by: Francisco Blas Izquierdo Riera (klondike) <klondike@klondike.es>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-01-05 09:40:16 -08:00
Francisco Blas Izquierdo Riera (klondike) db2aa7fd15 initramfs: allow again choice of the embedded initram compression algorithm
Choosing the appropriate compression option when using an embedded
initramfs can result in significant size differences in the resulting
data.

This is caused by avoiding double compression of the initramfs contents.
For example on my tests, choosing CONFIG_INITRAMFS_COMPRESSION_NONE when
compressing the kernel using XZ) results in up to 500KiB differences
(9MiB to 8.5MiB) in the kernel size as the dictionary will not get
polluted with uncomprensible data and may reuse kernel data too.

Despite embedding an uncompressed initramfs, a user may want to allow
for a compressed extra initramfs to be passed using the rd system, for
example to boot a recovery system.  9ba4bcb645 ("initramfs: read
CONFIG_RD_ variables for initramfs compression") broke that behavior by
making the choice based on CONFIG_RD_* instead of adding
CONFIG_INITRAMFS_COMPRESSION_LZ4.  Saddly, CONFIG_RD_* is also used to
choose the supported RD compression algorithms by the kernel and a user
may want to support more than one.

This patch also reverts commit 3e4e0f0a87 ("initramfs: remove
"compression mode" choice") restoring back the "compression mode" choice
and includes the CONFIG_INITRAMFS_COMPRESSION_LZ4 option which was never
added.

As a result the following options are added or readed affecting the embedded
initramfs compression:
  INITRAMFS_COMPRESSION_NONE Do no compression
  INITRAMFS_COMPRESSION_GZIP Compress using gzip
  INITRAMFS_COMPRESSION_BZIP2 Compress using bzip2
  INITRAMFS_COMPRESSION_LZMA Compress using lzma
  INITRAMFS_COMPRESSION_XZ Compress using xz
  INITRAMFS_COMPRESSION_LZO Compress using lzo
  INITRAMFS_COMPRESSION_LZ4 Compress using lz4

These depend on the corresponding CONFIG_RD_* option being set (except
NONE which has no dependencies).

This patch depends on the previous one (the previous version didn't) to
simplify the way in which the algorithm is chosen and keep backwards
compatibility with the behaviour introduced by 9ba4bcb645
("initramfs: read CONFIG_RD_ variables for initramfs compression").

Link: http://lkml.kernel.org/r/57EAD77B.7090607@klondike.es
Signed-off-by: Francisco Blas Izquierdo Riera (klondike) <klondike@klondike.es>
Cc: P J P <ppandit@redhat.com>
Cc: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-14 16:04:08 -08:00
Francisco Blas Izquierdo Riera (klondike) 35e669e1a2 initramfs: select builtin initram compression algorithm on KConfig instead of Makefile
Move the current builtin initram compression algorithm selection from
the Makefile into the INITRAMFS_COMPRESSION variable.  This makes
deciding algorithm precedence easier and would allow for overrides if
new algorithms want to be tested.

Link: http://lkml.kernel.org/r/57EAD769.1090401@klondike.es
Signed-off-by: Francisco Blas Izquierdo Riera (klondike) <klondike@klondike.es>
Cc: P J P <ppandit@redhat.com>
Cc: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-14 16:04:08 -08:00
Andi Kleen ec72c666fb usr/Kconfig: make initrd compression algorithm selection not expert
The kernel has support for (nearly) every compression algorithm known to
man, each to handle some particular microscopic niche.

Unfortunately all of these always get compiled in if you want to support
INITRDs, and can be only disabled when CONFIG_EXPERT is set.

I don't see why I need to set EXPERT just to properly configure the initrd
compression algorithms, and not always include every possible algorithm

Usually the initrd is just compressed with gzip anyways, at least that's
true on all distributions I use.

Remove the dependencies for initrd compression on CONFIG_EXPERT.

Make the various options just default y, which should be good enough to
not break any previous configuration.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-13 12:42:52 -08:00
Paul Bolle 3e4e0f0a87 initramfs: remove "compression mode" choice
Commit 9ba4bcb645 ("initramfs: read CONFIG_RD_ variables for initramfs
compression") removed the users of the various INITRAMFS_COMPRESSION_*
Kconfig symbols.  So since v3.13 the entire "Built-in initramfs
compression mode" choice is a set of knobs connected to nothing.  The
entire choice can safely be removed.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Cc: P J P <ppandit@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-06 16:08:14 -07:00
P J P 9ba4bcb645 initramfs: read CONFIG_RD_ variables for initramfs compression
When expert configuration option(CONFIG_EXPERT) is enabled, menuconfig
offers a choice of compression algorithm to compress initial ramfs image;
This choice is stored into CONFIG_RD_* variables.  But usr/Makefile uses
earlier INITRAMFS_COMPRESSION_* macros to build initial ramfs file.  Since
none of them is defined, resulting 'initramfs_data.cpio' file remains
un-compressed.

This patch updates the Makefile to use CONFIG_RD_* variables and adds
support for LZ4 compression algorithm.  Also updates the
'gen_initramfs_list.sh' script to check whether a selected compression
command is accessible or not.  And fall-back to default gzip(1)
compression when it is not.

Signed-off-by: P J P <prasad@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:26 +09:00
Michal Nazarewicz c725ee54c3 gen_init_cpio: avoid NULL pointer dereference and rework env expanding
getenv() may return NULL if given environment variable does not exist
which leads to NULL dereference when calling strncat.

Besides that, the environment variable name was copied to a temporary
env_var buffer, but this copying can be avoided by simply using the input
string.

Lastly, the whole loop can be greatly simplified by using the snprintf
function instead of the playing with strncat.

 By the way, the current implementation allows a recursive variable
 expansion, as in:

   $ echo 'out ${A} out ' | A='a ${B} a' B=b /tmp/a
   out a b a out

 I'm assuming this is just a side effect and not a conscious decision
 (especially as this may lead to infinite loop), but I didn't want to
 change this behaviour without consulting.

 If the current behaviour is deamed incorrect, I'll be happy to send
 a patch without recursive processing.

Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Jesper Juhl <jj@codesealer.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:12 +09:00
Kyungsik Lee e76e1fdfa8 lib: add support for LZ4-compressed kernel
Add support for extracting LZ4-compressed kernel images, as well as
LZ4-compressed ramdisk images in the kernel boot process.

Signed-off-by: Kyungsik Lee <kyungsik.lee@lge.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Florian Fainelli <florian@openwrt.org>
Cc: Yann Collet <yann.collet.73@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:30 -07:00
Jesper Juhl 59dbaf0415 gen_init_cpio: remove redundant empty line
Just a completely trivial patch to remove a completely redundant blank
line from usr/gen_init_cpio.c

Signed-off-by: Jesper Juhl <jj@codesealer.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-11-19 14:09:36 +01:00
Kees Cook 20f1de659b gen_init_cpio: avoid stack overflow when expanding
Fix possible overflow of the buffer used for expanding environment
variables when building file list.

In the extremely unlikely case of an attacker having control over the
environment variables visible to gen_init_cpio, control over the
contents of the file gen_init_cpio parses, and gen_init_cpio was built
without compiler hardening, the attacker can gain arbitrary execution
control via a stack buffer overflow.

  $ cat usr/crash.list
  file foo ${BIG}${BIG}${BIG}${BIG}${BIG}${BIG} 0755 0 0
  $ BIG=$(perl -e 'print "A" x 4096;') ./usr/gen_init_cpio usr/crash.list
  *** buffer overflow detected ***: ./usr/gen_init_cpio terminated

This also replaces the space-indenting with tabs.

Patch based on existing fix extracted from grsecurity.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Brad Spengler <spender@grsecurity.net>
Cc: PaX Team <pageexec@freemail.hu>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-25 14:37:53 -07:00
Randy Dunlap 0a4dd35c67 kconfig: update compression algorithm info
There have been new compression algorithms added without updating nearby
relevant descriptive text that refers to (a) the number of compression
algorithms and (b) the most recent one.  Fix these inconsistencies.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Reported-by: <qasdfgtyuiop@gmail.com>
Cc: Lasse Collin <lasse.collin@tukaani.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Alain Knaff <alain@knaff.lu>
Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31 17:49:33 -07:00
Michal Marek a8b8017c34 initramfs: Use KBUILD_BUILD_TIMESTAMP for generated entries
gen_init_cpio gets the current time and uses it for each symlink,
special file, and directory.  Grab the current time once and make it
possible to override it with the KBUILD_BUILD_TIMESTAMP variable for
reproducible builds.

Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-04-18 14:27:52 +02:00
David Rientjes 6a108a14fa kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT
The meaning of CONFIG_EMBEDDED has long since been obsoleted; the option
is used to configure any non-standard kernel with a much larger scope than
only small devices.

This patch renames the option to CONFIG_EXPERT in init/Kconfig and fixes
references to the option throughout the kernel.  A new CONFIG_EMBEDDED
option is added that automatically selects CONFIG_EXPERT when enabled and
can be used in the future to isolate options that should only be
considered for embedded systems (RISC architectures, SLOB, etc).

Calling the option "EXPERT" more accurately represents its intention: only
expert users who understand the impact of the configuration changes they
are making should enable it.

Reviewed-by: Ingo Molnar <mingo@elte.hu>
Acked-by: David Woodhouse <david.woodhouse@intel.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Greg KH <gregkh@suse.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Robin Holt <holt@sgi.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-20 17:02:05 -08:00
Lasse Collin 3ebe12439b decompressors: add boot-time XZ support
This implements the API defined in <linux/decompress/generic.h> which is
used for kernel, initramfs, and initrd decompression.  This patch together
with the first patch is enough for XZ-compressed initramfs and initrd;
XZ-compressed kernel will need arch-specific changes.

The buffering requirements described in decompress_unxz.c are stricter
than with gzip, so the relevant changes should be done to the
arch-specific code when adding support for XZ-compressed kernel.
Similarly, the heap size in arch-specific pre-boot code may need to be
increased (30 KiB is enough).

The XZ decompressor needs memmove(), memeq() (memcmp() == 0), and
memzero() (memset(ptr, 0, size)), which aren't available in all
arch-specific pre-boot environments.  I'm including simple versions in
decompress_unxz.c, but a cleaner solution would naturally be nicer.

Signed-off-by: Lasse 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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:25 -08:00
Linus Torvalds 0c05384a5a Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
  mkuboot.sh: Fail if mkimage is missing
  gen_init_cpio: checkpatch fixes
  gen_init_cpio: Avoid race between call to stat() and call to open()
  modpost: Fix address calculation in reloc_location()
  Make fixdep error handling more explicit
  checksyscalls: Fix stand-alone usage
  modpost: Put .zdebug* section on white list
  kbuild: fix interaction of CONFIG_IKCONFIG and KCONFIG_CONFIG
  kbuild: export linux/{a.out,kvm,kvm_para}.h on headers_install_all
  kbuild: introduce HDR_ARCH_LIST for headers_install_all
  headers_install: check exit status of unifdef
  gen_init_cpio: remove leading `/' from file names
  scripts/genksyms: fix header usage
  fixdep: use hash table instead of a single array
2011-01-10 08:27:52 -08:00
Andrew Morton a3c888fcda gen_init_cpio: checkpatch fixes
Cc: Jesper Juhl <jj@chaosbits.net>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-01-05 23:49:53 +01:00
Jesper Juhl 96aebafa63 gen_init_cpio: Avoid race between call to stat() and call to open()
In usr/gen_init_cpio.c::cpio_mkfile() a call to stat() is made based on
pathname, subsequently the file is open()'ed and then the value of the
initial stat() call is used to allocate a buffer. This is not safe since
the file may change between the call to stat() and the call to open().
Safer to just open() the file and then do fstat() using the filedescriptor
returned by open.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-12-29 15:06:54 +01:00
Michal Marek 8990c1bc4b Merge commit 'v2.6.37-rc1' into kbuild/kbuild 2010-12-14 22:01:55 +01:00
Thomas Chou 43f901fbc8 gen_init_cpio: remove leading `/' from file names
When we extracted the generated cpio archive using "cpio -id" command,
it complained,

cpio: Removing leading `/' from member names
var/run
cpio: Removing leading `/' from member names
var/lib
cpio: Removing leading `/' from member names
var/lib/misc

It is worse with the latest "cpio" or "pax", which tries to overwrite
the host file system with the leading '/'.

So the leading '/' of file names should be removed. This is consistent
with the initramfs come with major distributions such as Fedora or
Debian, etc.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Acked-by: Mike Frysinger<vapier@gentoo.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-12-02 14:28:50 +01:00
Hendrik Brueckner 1198c6d45a initramfs: Really fix build break on symbol-prefixed archs
Define the __initramfs_size variable using VMLINUX_SYMBOL() to take care
of symbol-prefixed architectures, for example, blackfin.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Mike Frysinger <vapier.adi@gmail.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>,
Cc: Michal Marek <mmarek@suse.cz>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[mmarek: leave out Makefile change, since d63f6d1 already takes care of the
 SYMBOL_PREFIX define]
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-12-01 13:13:21 +01:00
Geert Uytterhoeven 96f9359345 initramfs: Fix initramfs size for 32-bit arches
Commit ffe8018c34 ("initramfs: fix initramfs size calculation") broke
32-bit big-endian arches like (on ARAnyM):

    VFS: Cannot open root device "hda1" or unknown-block(3,1)
    Please append a correct "root=" boot option; here are the available partitions:
    fe80         1059408 nfhd8  (driver?)
      fe81          921600 nfhd8p1 00000000-0000-0000-0000-000000000nfhd8p1
      fe82          137807 nfhd8p2 00000000-0000-0000-0000-000000000nfhd8p2
    0200            3280 fd0  (driver?)
    0201            3280 fd1  (driver?)
    0300         1059408 hda  driver: ide-gd
      0301          921600 hda1 00000000-0000-0000-0000-000000000hda1
      0302          137807 hda2 00000000-0000-0000-0000-000000000hda2
    Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(3,1)

As pointed out by Kerstin Jonsson <kerstin.jonsson@ericsson.com>, this
is due to CONFIG_32BIT not being defined, so the initramfs size field is
done as a 64-bit quad.  On little-endian (like x86) this doesn matter,
but on a big-endian machine the 32-bit reads will see the (zero) high
bits.

Only mips, s390, and score set CONFIG_32BIT for 32-bit builds, so fix it for
all other 32-bit arches by inverting the logic and testing for CONFIG_64BIT,
which should be defined on all 64-bit arches.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
[ I think we should just make it "u64" on all architectures and get
  rid of the whole #ifdef CONFIG_xxBIT   - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-31 06:35:14 -07:00
Linus Torvalds c9e2a72ff1 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
  initramfs: Fix build break on symbol-prefixed archs
  initramfs: fix initramfs size calculation
  initramfs: generalize initramfs_data.xxx.S variants
  scripts/kallsyms: Enable error messages while hush up unnecessary warnings
  scripts/setlocalversion: update comment
  kbuild: Use a single clean rule for kernel and external modules
  kbuild: Do not run make clean in $(srctree)
  scripts/mod/modpost.c: fix commentary accordingly to last changes
  kbuild: Really don't clean bounds.h and asm-offsets.h
2010-10-28 15:13:55 -07:00
Hendrik Brueckner ffe8018c34 initramfs: fix initramfs size calculation
The size of a built-in initramfs is calculated in init/initramfs.c by
"__initramfs_end - __initramfs_start".  Those symbols are defined in the
linker script include/asm-generic/vmlinux.lds.h:

#define INIT_RAM_FS                                                     \
        . = ALIGN(PAGE_SIZE);                                           \
        VMLINUX_SYMBOL(__initramfs_start) = .;                          \
        *(.init.ramfs)                                                  \
        VMLINUX_SYMBOL(__initramfs_end) = .;

If the initramfs file has an odd number of bytes, the "__initramfs_end"
symbol points to an odd address, for example, the symbols in the
System.map might look like:

    0000000000572000 T __initramfs_start
    00000000005bcd05 T __initramfs_end	  <-- odd address

At least on s390 this causes a problem:

Certain s390 instructions, especially instructions for loading addresses
(larl) or branch addresses must be on even addresses.  The compiler loads
the symbol addresses with the "larl" instruction.  This instruction sets
the last bit to 0 and, therefore, for odd size files, the calculated size
is one byte less than it should be:

    0000000000540a9c <populate_rootfs>:
      540a9c:     eb cf f0 78 00 24       stmg    %r12,%r15,120(%r15),
      540aa2:     c0 10 00 01 8a af       larl    %r1,572000 <__initramfs_start>
      540aa8:     c0 c0 00 03 e1 2e       larl    %r12,5bcd04 <initramfs_end>
                                                  (Instead of  5bcd05)
      ...
      540abe:     1b c1                   sr      %r12,%r1

To fix the problem, this patch introduces the global variable
__initramfs_size, which is calculated in the "usr/initramfs_data.S" file.
The populate_rootfs() function can then use the start marker of the
.init.ramfs section and the value of __initramfs_size for loading the
initramfs.  Because the start marker and size is sufficient, the
__initramfs_end symbol is no longer needed and is removed.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Acked-by: Michal Marek <mmarek@suse.cz>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-09-29 16:28:59 +02:00
Hendrik Brueckner 6ae64e428f initramfs: generalize initramfs_data.xxx.S variants
Remove initramfs_data.{lzo,lzma,gz,bz2}.S variants and use a common
implementation in initramfs_data.S.  The common implementation expects the
file name of the initramfs to be defined in INITRAMFS_IMAGE.

Change the Makefile to set the INITRAMFS_IMAGE define symbol according
to the selected compression method.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Acked-by: Michal Marek <mmarek@suse.cz>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-09-29 16:28:59 +02:00
Stephan Sperber 681b3049dd Kconfig: delete duplicate word
Deleted a word which apeared twice.

Signed-off-by: Stephan Sperber <sperberstephan@googlemail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-08-23 15:35:15 +02:00
Albin Tonnerre 2a2a400f66 initramfs: add support for in-kernel initramfs compressed with LZO
Add the necessary parts to be enable the use of LZO-compressed initramfs
build into the kernel.

Signed-off-by: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:54 -07:00
Albin Tonnerre cacb246f8d Add LZO compression support for initramfs and old-style initrd
Signed-off-by: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Tested-by: Wu Zhangjin <wuzhangjin@gmail.com>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Russell King <rmk@arm.linux.org.uk>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-11 09:34:05 -08:00
Mike Frysinger 6d87fea4dd gen_init_cpio: fixed fwrite warning
On compilers with security warnings enabled by default, we get:

usr/gen_init_cpio.c: In function ‘cpio_mkfile’:
usr/gen_init_cpio.c:357: warning: ignoring return value of ‘fwrite’,
                                  declared with attribute warn_unused_result

So check the return value and handle errors accordingly.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2009-12-12 13:08:17 +01:00
Linus Torvalds c37efa9325 Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-next
* git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-next: (30 commits)
  Use macros for .data.page_aligned section.
  Use macros for .bss.page_aligned section.
  Use new __init_task_data macro in arch init_task.c files.
  kbuild: Don't define ALIGN and ENTRY when preprocessing linker scripts.
  arm, cris, mips, sparc, powerpc, um, xtensa: fix build with bash 4.0
  kbuild: add static to prototypes
  kbuild: fail build if recordmcount.pl fails
  kbuild: set -fconserve-stack option for gcc 4.5
  kbuild: echo the record_mcount command
  gconfig: disable "typeahead find" search in treeviews
  kbuild: fix cc1 options check to ensure we do not use -fPIC when compiling
  checkincludes.pl: add option to remove duplicates in place
  markup_oops: use modinfo to avoid confusion with underscored module names
  checkincludes.pl: provide usage helper
  checkincludes.pl: close file as soon as we're done with it
  ctags: usability fix
  kernel hacking: move STRIP_ASM_SYMS from General
  gitignore usr/initramfs_data.cpio.bz2 and usr/initramfs_data.cpio.lzma
  kbuild: Check if linker supports the -X option
  kbuild: introduce ld-option
  ...

Fix trivial conflict in scripts/basic/fixdep.c
2009-09-23 15:37:02 -07:00
Trevor Keith 5c72513843 Fix all -Wmissing-prototypes warnings in x86 defconfig
Signed-off-by: Trevor Keith <tsrk@tsrk.net>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-23 07:39:28 -07:00
Jaswinder Singh Rajput 78074cfc6e gitignore usr/initramfs_data.cpio.bz2 and usr/initramfs_data.cpio.lzma
usr/initramfs_data.cpio.bz2 and usr/initramfs_data.cpio.lzma are binary
files should be ignored

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-09-20 12:27:42 +02:00
Robert P. J. Day 0bc9f9e63c kbuild: correct initramfs compression comment
Fix the Makefile comment since bzip2 is now supported.

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-09-20 12:27:41 +02:00
H. Peter Anvin 1359096eac bzip2/lzma: quiet Kconfig warning for INITRAMFS_COMPRESSION_NONE
Impact: quiet Kconfig warning

It appears that Kconfig simply has no way to provide defaults for
entries that exist inside a conditionalized choice block.
Fortunately, it turns out we don't actually ever use
CONFIG_INITRAMFS_COMPRESSION_NONE, so we can just drop it for
everything outside the choice block.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-03-31 23:51:56 -07:00
H. Peter Anvin 4029792757 bzip2/lzma: don't ask for compression mode for the default initramfs
Impact: Kconfig noise reduction, documentation

The default initramfs is so small that it makes no sense to worry
about the additional memory taken by not double-compressing it.
Therefore, don't bug the user with it.

Also, improve the description of the option, which was downright
incorrect.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-03-28 17:27:15 -07:00
H. Peter Anvin 55d1d26f23 bzip2/lzma: consistently capitalize LZMA in Kconfig
Impact: message formatting

Consistently spell LZMA in all capitals, since it (unlike gzip or
bzip2) is an acronym.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-03-28 16:10:59 -07:00
H. Peter Anvin 337bed413e bzip2/lzma: clarify the meaning of the CONFIG_RD_ options
Impact: Kconfig clarification

Make it clear that the CONFIG_RD_* options are about what formats are
supported, not about what formats are actually being used.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-03-28 16:09:48 -07:00
H. Peter Anvin 73d8a12f05 bzip2/lzma: move CONFIG_RD_* options under CONFIG_EMBEDDED
Impact: reduce Kconfig noise

Move the options that control possible initramfs/initrd compressions
underneath CONFIG_EMBEDDED.  The only impact of leaving these options
set to y is additional code in the init section of the kernel; there
is no reason to burden non-embedded users with these options.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-03-28 15:49:08 -07:00
Alain Knaff ab76f3d771 bzip2/lzma: make internal initramfs compression configurable
Impact: Avoids silent environment dependency

Make builtin initramfs compression an explicit configurable.  The
previous version would pick a compression based on the binaries which
were installed on the system, which could lead to unexpected results.
It is now explicitly configured, and not having the appropriate
binaries installed on the build host is simply an error.

Signed-off-by: Alain Knaff <alain@knaff.lu>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-02-19 13:43:51 -08:00
Alain Knaff a26ee60f90 bzip2/lzma: fix built-in initramfs vs CONFIG_RD_GZIP
Impact: Resolves build failures in some configurations

Makes it possible to disable CONFIG_RD_GZIP . In that case, the
built-in initramfs will be compressed by whatever compressor is
available (bzip2 or lzma) or left uncompressed if none is available.

It also removes a couple of warnings which occur when no ramdisk
compression at all is chosen.

It also restores the select ZLIB_INFLATE in drivers/block/Kconfig
which somehow came missing. This is needed to activate compilation of
the stuff in zlib_deflate.

Signed-off-by: Alain Knaff <alain@knaff.lu>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-01-07 00:10:27 -08:00
H. Peter Anvin fb9a4ca982 bzip2/lzma: move initrd/ramfs options out of BLK_DEV
Impact: Partial resolution of build failure

Move the initrd/initramfs configuration options from
drivers/block/Kconfig to usr/Kconfig, since they do not and should not
depend on CONFIG_BLK_DEV.  This fixes builds when CONFIG_BLK_DEV=n.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-01-07 00:03:49 -08:00
Sally, Gene 3b1ec9fb81 kbuild: gen_init_cpio expands shell variables in file names
Modify gen_init_cpio so that lines that specify files can contain
what looks like a shell variable that's expanded during processing.

For example:

   file /sbin/kinit ${RFS_BASE}/usr/src/klibc/kinit/kinit 0755 0 0

given RFS_BASE is "/some/directory" in the environment

would be expanded to

   file /sbin/kinit /some/directory/usr/src/klibc/kinit/kinit 0755 0 0

If several environment variables appear in a line, they are all expanded
with processing happening from left to right.
Undefined variables expand to a null string.
Syntax errors stop processing, letting the existing error handling
show the user offending line.

This patch helps embedded folks who frequently create several
RFS directories and then switch between them as they're tuning
an initramfs.

Signed-off-by: gene.sally@timesys.com
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-12-03 21:32:03 +01:00
Mike Frysinger f2434ec1e0 kbuild: add support for reading stdin with gen_init_cpio
Treat an argument of "-" as meaning "read stdin for cpio files" so
gen_init_cpio can be piped into.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-07-16 21:15:52 +02:00
Alexey Dobriyan 3f1b0e1f28 .gitignore update
headers_install by default puts headers into usr/include/ .
They're auto-generated, so should be ignored.

Same for *.orig, *.rej .

Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:52 -07:00