mirror of https://github.com/mkerrisk/man-pages
msr.4: New page documenting x86 CPU MSR access device
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
This commit is contained in:
parent
f5c7f16bf5
commit
027ac74c30
|
@ -0,0 +1,56 @@
|
|||
.\" Copyright (c) 2009 by Andi Kleen <andi@firstfloor.org>
|
||||
.\" Some sentences copied from comments in arch/x86/kernel/msr.c
|
||||
.\"
|
||||
.\" 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.\" manual page may be incorrect or out-of-date.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.
|
||||
.\"
|
||||
.TH MSR 4 2009-03-31 "Linux" "Linux Programmer's Manual"
|
||||
.SH NAME
|
||||
msr \- x86 CPU MSR access device
|
||||
.SH DESCRIPTION
|
||||
.I /dev/cpu/CPUNUM/msr
|
||||
provides an interface to read and write the model-specific
|
||||
registers (MSRs) of an x86 CPU.
|
||||
.I CPUNUM
|
||||
is the number of the CPU to access as listed in
|
||||
.IR /proc/cpuinfo .
|
||||
|
||||
The register access is done by opening the file and seeking
|
||||
to the MSR number as offset in the file, and then
|
||||
reading or writing in chunks of 8 bytes.
|
||||
An I/O transfer of more than 8 bytes means multiple reads or writes
|
||||
of the same register.
|
||||
|
||||
This file is protected so that it can only be read and written by the user
|
||||
.IR root ,
|
||||
or members of the group
|
||||
.IR root .
|
||||
.SH NOTES
|
||||
The
|
||||
.I msr
|
||||
driver is not auto-loaded.
|
||||
On modular kernels you might need to use the following command
|
||||
to load it explicitly before use:
|
||||
|
||||
$ \fImodprobe msr\fP
|
||||
.SH SEE ALSO
|
||||
Intel Corporation Intel 64 and IA-32 Architectures
|
||||
Software Developer's Manual Volume 3B Appendix B
|
||||
for an overview of the Intel CPU MSRs.
|
Loading…
Reference in New Issue