NAME

       msr - x86 CPU MSR access device

DESCRIPTION

       /dev/cpu/CPUNUM/msr provides an interface to read and write the model-specific registers (MSRs) of an x86
       CPU.  CPUNUM is the number of the CPU to access as listed in /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 be read and written only by the user root, or members of the  group
       root.

NOTES

       The  msr  driver  is  not auto-loaded.  On modular kernels you might need to use the following command to
       load it explicitly before use:

           $ modprobe msr

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.

COLOPHON

       This  page  is  part  of  release 3.54 of the Linux man-pages project.  A description of the project, and
       information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.