Section: Linux Programmer's Manual (4)
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msr - x86 CPU MSR access device
provides an interface to read and write the model-specific
registers (MSRs) of an x86 CPU.
is the number of the CPU to access as listed in
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
or members of the group
driver is not auto-loaded.
On modular kernels you might need to use the following command
to load it explicitly before use:
$ modprobe msr
Intel Corporation Intel 64 and IA-32 Architectures
Software Developer's Manual Volume 3B Appendix B,
for an overview of the Intel CPU MSRs.
This page is part of release 3.74 of the Linux
A description of the project,
information about reporting bugs,
and the latest version of this page,
can be found at
- SEE ALSO