blktests: call for agreement to relicense GPL-2.0 files

[Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>]

Hello blktests contributors,

Recent discussion unveiled a license inconsistency [1]. Currently, each file of
blktests has one of the licenses: GPL-2.0, GPL-2.0+ or GPL-3.0+. Majority of the
blktests code has GPL-3.0+, so the effective main license is GPL-3.0+ (e.g.,
check, common/rc). However, GPL-2.0 and GPL-3.0 are not compatible with each
other [2]. Because the majority of blktests is GPL-3.0+, blktests cannot contain
GPL-2.0 files. All files shall be GPL-2.0+ or GPL-3.0+.

  [1] https://lore.kernel.org/linux-block/20260626045650.GA8752@lst.de/
  [2] https://www.gnu.org/licenses/gpl-faq.html#v2v3Compatibility

As of July 2026, seven files below have GPL-2.0. It is desired to change their
license to GPL-2.0+ (or GPL-3.0+). The list below shows Authors and Contributors
of each file. "Author" means the original file creator who set the license
GPL-2.0. "Contributor" means those who made changes to the files later on.

1) block/029
    Author: Bart Van Assche <bvanassche@acm.org>
    Contributors: Yi Zhang <yi.zhang@redhat.com>
		  Christoph Hellwig <hch@lst.de>
		  Li Zhijian <lizhijian@fujitsu.com>

2) block/030
    Author: Bart Van Assche <bvanassche@acm.org>
    Contributors: Christoph Hellwig <hch@lst.de>
		  Li Zhijian <lizhijian@fujitsu.com>
		  Akinobu Mita <akinobu.mita@gmail.com>

3) block/031
    Author: Bart Van Assche <bvanassche@acm.org>
    Contributors: Yi Zhang <yi.zhang@redhat.com>
		  Christoph Hellwig <hch@lst.de>
		  Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>

4) block/040
    Author: Ming Lei <ming.lei@redhat.com>

5) block/042
    Author: Keith Busch <kbusch@kernel.org>
    Contributors: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
		  John Pittman <jpittman@redhat.com>

6) block/043
    Author: Keith Busch <kbusch@kernel.org>
    Contributors: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>

7) src/dio-offsets.c
    Author: Keith Busch <kbusch@kernel.org>
    Contributors: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
		  Bart Van Assche <bvanassche@acm.org>


To the authors and the contributors,

  I would like to call for your responses. Please let us know if you agree to
  modify the license of the files from GPL-2.0 to GPL-2.0+ (or GPL-3.0+).


I will wait for a few weeks to gather responses. Once agreement gets
estabilished, I will ask the authors to submit patches to make the license
change. Any other general comments on this topic will be appreciated also.

And as one of the contributors, here I express my agreement to change the
license of the files :)