linux-toradex.git/usr/Makefile, branch v5.3-rc6

kbuild: compile-test exported headers to ensure they are self-contained

2019-07-08T14:13:57+00:00

Multiple people have suggested compile-testing UAPI headers to ensure
they can be really included from user-space. "make headers_check" is
obviously not enough to catch bugs, and we often leak unresolved
references to user-space.

Use the new header-test-y syntax to implement it. Please note exported
headers are compile-tested with a completely different set of compiler
flags. The header search path is set to $(objtree)/usr/include since
exported headers should not include unexported ones.

We use -std=gnu89 for the kernel space since the kernel code highly
depends on GNU extensions. On the other hand, UAPI headers should be
written in more standardized C, so they are compiled with -std=c90.
This will emit errors if C++ style comments, the keyword 'inline', etc.
are used. Please use C style comments (/* ... */), '__inline__', etc.
in UAPI headers.

There is additional compiler requirement to enable this test because
many of UAPI headers include , , ,
etc. directly or indirectly. You cannot use kernel.org pre-built
toolchains [1] since they lack .

I reused CONFIG_CC_CAN_LINK to check the system header availability.
The intention is slightly different, but a compiler that can link
userspace programs provide system headers.

For now, a lot of headers need to be excluded because they cannot
be compiled standalone, but this is a good start point.

[1] https://mirrors.edge.kernel.org/pub/tools/crosstool/index.html

Signed-off-by: Masahiro Yamada 
Reviewed-by: Sam Ravnborg

user/Makefile: Fix typo and capitalization in comment section

2018-12-10T15:18:03+00:00

Signed-off-by: Eugen Cazacu 
Signed-off-by: Masahiro Yamada

initramfs: move gen_initramfs_list.sh from scripts/ to usr/

2018-08-22T14:21:44+00:00

scripts/gen_initramfs_list.sh is only invoked from usr/Makefile.
Move it so that all tools to create initramfs are self-contained
in the usr/ directory.

Signed-off-by: Masahiro Yamada

initramfs: fix initramfs rebuilds w/ compression after disabling

2017-11-03T14:39:19+00:00

This is a follow-up to commit 57ddfdaa9a72 ("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: db2aa7fd15e8 ("initramfs: allow again choice of the embedded initramfs compression algorithm")
Fixes: 9e3596b0c653 ("kbuild: initramfs cleanup, set target from Kconfig")
Signed-off-by: Florian Fainelli 
Cc: "Francisco Blas Izquierdo Riera (klondike)" 
Cc: Nicholas Piggin 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55+00:00

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 
Reviewed-by: Philippe Ombredanne 
Reviewed-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

kbuild: initramfs cleanup, set target from Kconfig

2017-01-05T17:40:16+00:00

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) 
Signed-off-by: Nicholas Piggin 
Signed-off-by: Linus Torvalds

kbuild: initramfs fix dependency checking for compressed target

2017-01-05T17:40:16+00:00

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: 35e669e1a254 ("initramfs: select builtin initram compression algorithm on KConfig instead of Makefile")
Reviewed-by: Francisco Blas Izquierdo Riera (klondike) 
Signed-off-by: Nicholas Piggin 
Signed-off-by: Linus Torvalds

initramfs: select builtin initram compression algorithm on KConfig instead of Makefile

2016-12-15T00:04:08+00:00

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) 
Cc: P J P 
Cc: Paul Bolle 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

initramfs: read CONFIG_RD_ variables for initramfs compression

2013-11-13T03:09:26+00:00

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 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

decompressors: add boot-time XZ support

2011-01-13T16:03:25+00:00

This implements the API defined in  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 
Cc: "H. Peter Anvin" 
Cc: Alain Knaff 
Cc: Albin Tonnerre 
Cc: Phillip Lougher 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds