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
     

08 Oct, 2016

5 commits

  • The change adds an option to a user with CONFIG_WATCHDOG_SYSFS and
    CONFIG_WATCHDOG_PRETIMEOUT_GOV enabled to get information about all
    registered watchdog pretimeout governors by reading watchdog device
    attribute named "pretimeout_available_governors".

    Signed-off-by: Vladimir Zapolskiy
    Reviewed-by: Guenter Roeck
    Reviewed-by: Wolfram Sang
    Tested-by: Wolfram Sang
    Signed-off-by: Guenter Roeck
    Signed-off-by: Wim Van Sebroeck

    Vladimir Zapolskiy
     
  • The change converts watchdog device attribute "pretimeout_governor" from
    read-only to read-write type to allow users to select a desirable
    watchdog pretimeout governor in runtime, e.g.

    % echo -n panic > /sys/..../watchdog/watchdog0/pretimeout

    To get this working a list of registered pretimeout governors is created
    and a new helper function watchdog_pretimeout_governor_set() is exported
    to watchdog_dev.c.

    If a selected governor is gone, a watchdog device pretimeout notification
    is delegated to a default built-in pretimeout governor.

    Signed-off-by: Vladimir Zapolskiy
    Reviewed-by: Guenter Roeck
    Reviewed-by: Wolfram Sang
    Tested-by: Wolfram Sang
    Signed-off-by: Guenter Roeck
    Signed-off-by: Wim Van Sebroeck

    Vladimir Zapolskiy
     
  • The change adds panic watchdog pretimeout governor, on watchdog
    pretimeout event the kernel shall panic. In general watchdog
    pretimeout event means that something essentially bad is going on the
    system, for example a process scheduler stalls or watchdog feeder is
    killed due to OOM, so printing out information attendant to panic and
    before likely unavoidable reboot caused by a watchdog may help to
    determine a root cause of the issue.

    Signed-off-by: Vladimir Zapolskiy
    Reviewed-by: Guenter Roeck
    Reviewed-by: Wolfram Sang
    Tested-by: Wolfram Sang
    Signed-off-by: Guenter Roeck
    Signed-off-by: Wim Van Sebroeck

    Vladimir Zapolskiy
     
  • The change adds noop watchdog pretimeout governor, only an
    informational message is printed to the kernel log buffer when a
    watchdog triggers a pretimeout event.

    While introducing the first pretimeout governor the selected design
    assumes that the default pretimeout governor is selected by its name
    and it is always built-in, thus the default pretimeout governor can
    not be unregistered and the correspondent check can be removed from
    the watchdog_unregister_governor() function.

    Signed-off-by: Vladimir Zapolskiy
    Reviewed-by: Guenter Roeck
    Reviewed-by: Wolfram Sang
    Tested-by: Wolfram Sang
    Signed-off-by: Guenter Roeck
    Signed-off-by: Wim Van Sebroeck

    Vladimir Zapolskiy
     
  • The change adds a simple watchdog pretimeout framework infrastructure,
    its purpose is to allow users to select a desired handling of watchdog
    pretimeout events, which may be generated by some watchdog devices.

    A user selects a default watchdog pretimeout governor during
    compilation stage.

    Watchdogs with WDIOF_PRETIMEOUT capability now have one more device
    attribute in sysfs, pretimeout_governor attribute is intended to display
    the selected watchdog pretimeout governor.

    The framework has no impact at runtime on watchdog devices with no
    WDIOF_PRETIMEOUT capability set.

    Signed-off-by: Vladimir Zapolskiy
    Reviewed-by: Guenter Roeck
    Reviewed-by: Wolfram Sang
    Tested-by: Wolfram Sang
    Signed-off-by: Guenter Roeck
    Signed-off-by: Wim Van Sebroeck

    Vladimir Zapolskiy