proc mmu_off foo {
        set reg [rrd msr]
        set reg [split $reg ": "]
        set reg [lindex $reg 5]
        set reg "0x$reg"
        set reg [expr {$reg & ~8192}]
        set reg [expr {$reg & ~16384}]
        set reg [format "0x%08x" $reg]
        rwr msr $reg
}


proc mmu_on foo {
        set reg [rrd msr]
        set reg [split $reg ": "]
        set reg [lindex $reg 5]
        set reg "0x$reg"
        set reg [expr {$reg | 8192}]
        set reg [expr {$reg | 16384}]
        set reg [format "0x%08x" $reg]
        rwr msr $reg
}