msr — x86 CPU MSR access device
an interface to read and write the model-specific registers
(MSRs) of an x86 CPU.
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
members of the group
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
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 4.07 of the Linux
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Copyright (c) 2009 Intel Corporation, Author Andi Kleen
Some sentences copied from comments in arch/x86/kernel/msr.c
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