Some platforms define their processors in this manner:
Device (SCK0)
{
Name (_HID, "ACPI0004" /* Module Device */) // _HID: Hardware ID
Name (_UID, "CPUSCK0") // _UID: Unique ID
Processor (CP00, 0x00, 0x00000410, 0x06){}
Processor (CP01, 0x02, 0x00000410, 0x06){}
Processor (CP02, 0x04, 0x00000410, 0x06){}
Processor (CP03, 0x06, 0x00000410, 0x06){}
Processor (CP04, 0x01, 0x00000410, 0x06){}
Processor (CP05, 0x03, 0x00000410, 0x06){}
Processor (CP06, 0x05, 0x00000410, 0x06){}
Processor (CP07, 0x07, 0x00000410, 0x06){}
Processor (CP08, 0xFF, 0x00000410, 0x06){}
Processor (CP09, 0xFF, 0x00000410, 0x06){}
Processor (CP0A, 0xFF, 0x00000410, 0x06){}
Processor (CP0B, 0xFF, 0x00000410, 0x06){}
...
The processors marked as 0xff are invalid, there are only 8 of them in
this case.
So do not print an error on ids == 0xff, just print an info message.
Actually, we could return ENODEV even on the first CPU with ID 0xff, but
ACPI spec does not forbid the 0xff value to be a processor ID. Given
0xff could be a correct one, we would break working systems if we
returned ENODEV.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.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.