msr − x86
CPU MSR access device
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.
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.
driver is not auto-loaded. On modular kernels you might need
to use the following command to load it explicitly before
Corporation Intel 64 and IA-32 Architectures Software
Developer’s Manual Volume 3B Appendix B, for an
overview of the Intel CPU MSRs.
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part of release 4.04 of the Linux man-pages project.
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