grub: rdmsr
16.3.59 rdmsr
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-- Command:: rdmsr 0xADDR [-v VARNAME]
Read a model-specific register at address 0xADDR. If the parameter
'-v' is used and an environment variable VARNAME is given, set that
environment variable to the value that was read.
Please note that on SMP systems, reading from a MSR that has a
scope per hardware thread, implies that the value that is returned
only applies to the particular cpu/core/thread that runs the
command.
Also, if you specify a reserved or unimplemented MSR address, it
will cause a general protection exception (which is not currently
being handled) and the system will reboot.