02 Nov, 2017

1 commit

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

    Greg Kroah-Hartman
     

11 Mar, 2017

1 commit

  • The purgatory code defines global variables which are referenced via a
    symbol lookup in the kexec code (core and arch).

    A recent commit addressing sparse warnings made these static and thereby
    broke kexec_file.

    Why did this happen? Simply because the whole machinery is undocumented and
    lacks any form of forward declarations. The variable names are unspecific
    and lack a prefix, so adding forward declarations creates shadow variables
    in the core code. Aside of that the code relies on magic constants and
    duplicate struct definitions with no way to ensure that these things stay
    in sync. The section placement of the purgatory variables happened by
    chance and not by design.

    Unbreak kexec and cleanup the mess:

    - Add proper forward declarations and document the usage
    - Use common struct definition
    - Use the proper common defines instead of magic constants
    - Add a purgatory_ prefix to have a proper name space
    - Use ARRAY_SIZE() instead of a homebrewn reimplementation
    - Add proper sections to the purgatory variables [ From Mike ]

    Fixes: 72042a8c7b01 ("x86/purgatory: Make functions and variables static")
    Reported-by: Mike Galbraith <
    Signed-off-by: Thomas Gleixner
    Cc: Nicholas Mc Guire
    Cc: Borislav Petkov
    Cc: Vivek Goyal
    Cc: "Tobin C. Harding"
    Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1703101315140.3681@nanos
    Signed-off-by: Thomas Gleixner

    Thomas Gleixner