2d8b39a62a
If there are neither processor objects nor processor device objects in the ACPI tables, the per-CPU processors table will not be initialized and attempting to dereference pointers from there will cause the kernel to crash. This happens in acpi_processor_ppc_init() and acpi_thermal_cpufreq_init() after commitd15ce41273("ACPI: cpufreq: Switch to QoS requests instead of cpufreq notifier") which didn't add the requisite NULL pointer checks in there. Add the NULL pointer checks to acpi_processor_ppc_init() and acpi_thermal_cpufreq_init(), and to the corresponding "exit" routines. While at it, drop redundant return instructions from acpi_processor_ppc_init() and acpi_thermal_cpufreq_init(). Fixes:d15ce41273("ACPI: cpufreq: Switch to QoS requests instead of cpufreq notifier") Reported-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@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.