+++ /dev/null
-.\" Copyright (c) 2009 Intel Corporation, Author Andi Kleen
-.\" Description based on comments in arch/x86/kernel/cpuid.c
-.\"
-.\" %%%LICENSE_START(VERBATIM)
-.\" Permission is granted to make and distribute verbatim copies of this
-.\" manual provided the copyright notice and this permission notice are
-.\" preserved on all copies.
-.\"
-.\" Permission is granted to copy and distribute modified versions of this
-.\" manual under the conditions for verbatim copying, provided that the
-.\" entire resulting derived work is distributed under the terms of a
-.\" permission notice identical to this one.
-.\"
-.\" Since the Linux kernel and libraries are constantly changing, this
-.\" manual page may be incorrect or out-of-date. The author(s) assume no
-.\" responsibility for errors or omissions, or for damages resulting from
-.\" the use of the information contained herein. The author(s) may not
-.\" have taken the same level of care in the production of this manual,
-.\" which is licensed free of charge, as they might when working
-.\" professionally.
-.\"
-.\" Formatted or processed versions of this manual, if unaccompanied by
-.\" the source, must acknowledge the copyright and authors of this work.
-.\" %%%LICENSE_END
-.\"
-.TH CPUID 4 2009-03-31 "Linux" "Linux Programmer's Manual"
-.SH NAME
-cpuid \- x86 CPUID access device
-.SH DESCRIPTION
-CPUID provides an interface for querying information about the x86 CPU.
-
-This device is accessed by
-.BR lseek (2)
-or
-.BR pread (2)
-to the appropriate CPUID level and reading in chunks of 16 bytes.
-A larger read size means multiple reads of consecutive levels.
-
-The lower 32 bits of the file position is used as the incoming
-.IR %eax ,
-and the upper 32 bits of the file position as the incoming
-.IR %ecx ,
-the latter intended for "counting"
-.I eax
-levels like
-.IR eax=4 .
-
-This driver uses
-.IR /dev/cpu/CPUNUM/cpuid ,
-where
-.I CPUNUM
-is the minor number,
-and on an SMP box will direct the access to CPU
-.I CPUNUM
-as listed in
-.IR /proc/cpuinfo .
-
-This file is protected so that it can be read only by the user
-.IR root ,
-or members of the group
-.IR root .
-.SH NOTES
-The CPUID instruction can be directly executed by a program
-using inline assembler.
-However this device allows convenient
-access to all CPUs without changing process affinity.
-
-Most of the information in
-.I cpuid
-is reported by the kernel in cooked form either in
-.I /proc/cpuinfo
-or through subdirectories in
-.IR /sys/devices/system/cpu .
-Direct CPUID access through this device should only
-be used in exceptional cases.
-
-The
-.I cpuid
-driver is not auto-loaded.
-On modular kernels you might need to use the following command
-to load it explicitly before use:
-
- $ \fImodprobe cpuid\fP
-
-There is no support for CPUID functions that require additional
-input registers.
-
-Very old x86 CPUs don't support CPUID.
-.SH SEE ALSO
-Intel Corporation, Intel 64 and IA-32 Architectures
-Software Developer's Manual Volume 2A:
-Instruction Set Reference, A-M, 3-180 CPUID reference.
-
-Intel Corporation, Intel Processor Identification and
-the CPUID Instruction, Application note 485.
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I man-pages
-project.
-A description of the project,
-information about reporting bugs,
-and the latest version of this page,
-can be found at
-\%http://www.kernel.org/doc/man\-pages/.
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