View source for MSR

Model-Specific Registers: per-processor extensions in the x86 family, discoverable via [[cpuid]]. Unlike the [[cpuid|CPUID]] registers, many are configurable. MSR's are read and written at the assembly level via the <tt>RDMSR</tt> and <tt>WRMSR</tt> instructions. Some MSRs of note include:
* Accessing the [[Time Stamp Counter]] via '''TSC''' (0x0000_0010)
* Managing SYSENTER/SYSEXIT parameters via '''SEP_{SEL,ESP,EIP}''' (0x0000_0174, 5 and 6)
* Managing SYSCALL/SYSRET parameters via '''STAR''' (0xC000_0081)
* Managing the [[Page Attribute Tables]] via '''PAT''' (0x0000_0277)
* Managing [[MTRR]]s and [[MCA]]

==See Also==
* [[Performance Counters]]

[[Category: x86]]
[[Category: Hardware]]