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Diffstat (limited to 'Documentation/process/license-rules.rst')
| -rw-r--r-- | Documentation/process/license-rules.rst | 127 |
1 files changed, 119 insertions, 8 deletions
diff --git a/Documentation/process/license-rules.rst b/Documentation/process/license-rules.rst index 2bb8c0fc2238..2ef44ada3f11 100644 --- a/Documentation/process/license-rules.rst +++ b/Documentation/process/license-rules.rst @@ -62,7 +62,7 @@ License identifier syntax The SPDX license identifier in kernel files shall be added at the first possible line in a file which can contain a comment. For the majority - or files this is the first line, except for scripts which require the + of files this is the first line, except for scripts which require the '#!PATH_TO_INTERPRETER' in the first line. For those scripts the SPDX identifier goes into the second line. @@ -234,13 +234,13 @@ kernel, can be broken down into: | -2. Not recommended licenses: +2. Deprecated licenses: These licenses should only be used for existing code or for importing code from a different project. These licenses are available from the directory:: - LICENSES/other/ + LICENSES/deprecated/ in the kernel source tree. @@ -250,14 +250,14 @@ kernel, can be broken down into: Examples:: - LICENSES/other/ISC + LICENSES/deprecated/ISC Contains the Internet Systems Consortium license text and the required metatags:: - LICENSES/other/ZLib + LICENSES/deprecated/GPL-1.0 - Contains the ZLIB license text and the required metatags. + Contains the GPL version 1 license text and the required metatags. Metatags: @@ -281,7 +281,56 @@ kernel, can be broken down into: | -3. _`Exceptions`: +3. Dual Licensing Only + + These licenses should only be used to dual license code with another + license in addition to a preferred license. These licenses are available + from the directory:: + + LICENSES/dual/ + + in the kernel source tree. + + The files in this directory contain the full license text and + `Metatags`_. The file names are identical to the SPDX license + identifier which shall be used for the license in source files. + + Examples:: + + LICENSES/dual/MPL-1.1 + + Contains the Mozilla Public License version 1.1 license text and the + required metatags:: + + LICENSES/dual/Apache-2.0 + + Contains the Apache License version 2.0 license text and the required + metatags. + + Metatags: + + The metatag requirements for 'other' licenses are identical to the + requirements of the `Preferred licenses`_. + + File format example:: + + Valid-License-Identifier: MPL-1.1 + SPDX-URL: https://spdx.org/licenses/MPL-1.1.html + Usage-Guide: + Do NOT use. The MPL-1.1 is not GPL2 compatible. It may only be used for + dual-licensed files where the other license is GPL2 compatible. + If you end up using this it MUST be used together with a GPL2 compatible + license using "OR". + To use the Mozilla Public License version 1.1 put the following SPDX + tag/value pair into a comment according to the placement guidelines in + the licensing rules documentation: + SPDX-License-Identifier: MPL-1.1 + License-Text: + Full license text + +| + +4. _`Exceptions`: Some licenses can be amended with exceptions which grant certain rights which the original license does not. These exceptions are available @@ -368,7 +417,69 @@ kernel, can be broken down into: All SPDX license identifiers and exceptions must have a corresponding file -in the LICENSE subdirectories. This is required to allow tool +in the LICENSES subdirectories. This is required to allow tool verification (e.g. checkpatch.pl) and to have the licenses ready to read and extract right from the source, which is recommended by various FOSS organizations, e.g. the `FSFE REUSE initiative <https://reuse.software/>`_. + +_`MODULE_LICENSE` +----------------- + + Loadable kernel modules also require a MODULE_LICENSE() tag. This tag is + neither a replacement for proper source code license information + (SPDX-License-Identifier) nor in any way relevant for expressing or + determining the exact license under which the source code of the module + is provided. + + The sole purpose of this tag is to provide sufficient information + whether the module is free software or proprietary for the kernel + module loader and for user space tools. + + The valid license strings for MODULE_LICENSE() are: + + ============================= ============================================= + "GPL" Module is licensed under GPL version 2. This + does not express any distinction between + GPL-2.0-only or GPL-2.0-or-later. The exact + license information can only be determined + via the license information in the + corresponding source files. + + "GPL v2" Same as "GPL". It exists for historic + reasons. + + "GPL and additional rights" Historical variant of expressing that the + module source is dual licensed under a + GPL v2 variant and MIT license. Please do + not use in new code. + + "Dual MIT/GPL" The correct way of expressing that the + module is dual licensed under a GPL v2 + variant or MIT license choice. + + "Dual BSD/GPL" The module is dual licensed under a GPL v2 + variant or BSD license choice. The exact + variant of the BSD license can only be + determined via the license information + in the corresponding source files. + + "Dual MPL/GPL" The module is dual licensed under a GPL v2 + variant or Mozilla Public License (MPL) + choice. The exact variant of the MPL + license can only be determined via the + license information in the corresponding + source files. + + "Proprietary" The module is under a proprietary license. + This string is solely for proprietary third + party modules and cannot be used for modules + which have their source code in the kernel + tree. Modules tagged that way are tainting + the kernel with the 'P' flag when loaded and + the kernel module loader refuses to link such + modules against symbols which are exported + with EXPORT_SYMBOL_GPL(). + ============================= ============================================= + + + |