3b2f17ad17
To avoid a NULL pointer dereference when the kernel supports the new feature but the tooling still hasn't an entry for it. This happened with the recently added PERF_COUNT_SW_CGROUP_SWITCHES software event. Reported-by: Thomas Richter <tmricht@linux.ibm.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Link: https://lore.kernel.org/linux-perf-users/YKVESEKRjKtILhog@kernel.org/ Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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.