f86854a2e7
Currently there's a bug in the module subsystem [0] preventing load of the PHY driver module on certain systems (as one symptom). This results in a NPE on such systems for the following reason: Instead of the correct PHY driver the genphy driver is loaded that doesn't implement the read_page/write_page callbacks. Every call to phy_read_paged() et al will result in a NPE therefore. In parallel to fixing the root cause we should make sure that this one and maybe similar issues in other subsystems don't result in a NPE in phylib. So let's check for the callbacks before using them and warn once if they are not available. [0] https://marc.info/?t=157072642100001&r=1&w=2 Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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.