1b6266ebe3
Code is emitting the following error message during boot on systems without PMU hardware support while probing NMI capability. NMI watchdog: Perf event create on CPU 0 failed with -2 This error is emitted as the perf subsystem returns -ENOENT due to lack of PMUs in the system. It is followed by the warning that NMI watchdog is disabled: NMI watchdog: Perf NMI watchdog permanently disabled While NMI disabled information is useful for ordinary users, seeing a PERF event create failed with error code -2 is not. Reduce the message severity to debug so that if debugging is still possible in case the error code returned by perf is required for analysis. Signed-off-by: Sinan Kaya <okaya@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Don Zickus <dzickus@redhat.com> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Colin Ian King <colin.king@canonical.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=599368 Link: https://lkml.kernel.org/r/20180803060943.2643-1-okaya@kernel.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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.