Find out if CPU supports hardware vitualization Intel VT-X or AMD-V

grep --color vmx /proc/cpuinfo

or 

# grep --color svm /proc/cpuinfo


http://www.cyberciti.biz/faq/linux-xen-vmware-kvm-intel-vt-amd-v-support/

Enable and Disable maskable Interrrupts

Disable Interrrupts:
eflags &= (0xffffffff-0x200);

Enable Interrupts:
eflags |= (0x200);

http://en.wikipedia.org/wiki/FLAGS_register

Find 8 bits CPU ID from IO APIC redirection table entry

Find the CPU ID from IO APIC redirection table

use read and write everything tool. Specify index register: FEC00000, and Data register: FEC00010

First of all, you need to find out where is the IO APIC memory address, which is FEC00000 in our case, Then the address + 0x10 is the data register,

The first IRQ has indexes 0x10 and 0x11, the second 0x12 and 0x13, the third 0x14 and 0x15

CPU ID is the 56 – 63 bits of the redirection table entry

cpufreq: CPU_Frequency_Scaling

https://wiki.archlinux.org/index.php/CPU_Frequency_Scaling
http://www.mjmwired.net/kernel/Documentation/cpu-freq/governors.txt

CPU

command to get cpu infomation:
cat /proc/cpuinfo
In Ubuntu, you could install command cpuid, and run:$cpuid

AMD Athlon 64 3500+
CPUID example: 40ff2
Model stepping:DH-F2