f8850206e1
The existing use of ktime_get_real_ns() in the timestamps from the GPIO events is dubious. We have had several discussions about this timestamp, and it is unclear whether userspace has ever taken into account that a timestamp from ktime_get_real_ns() can actually move backwards in time relative the previous timetamp, and userspace is more likely to expect a monotonic counter. Background: https://lore.kernel.org/linux-gpio/CAK8P3a1Skvm48sje8FNDPLYqyz9Lf8q0qX1QETWtyZTxuX4k1g@mail.gmail.com/ https://marc.info/?l=linux-gpio&m=151661955709074&w=2 The change is ABI incompatible, but incompatible in a way that is IMO more likely to fix future bugs rather than break current userspace. To the best of my knowledge all userspace expects a monotonic timestamp and users are just lucky that they very seldom move backwards in time. Cc: Arnd Bergmann <arnd@arndb.de> Acked-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.