"KVM is disabled by BIOS" messages are seen in logs even-though processor support Virtualization

“KVM is disabled by BIOS” message appears in logs ..

Once I noticed, I am not able to use virtualization in my test system . I know my test system support Full virtualization , still no luck.. If you came across something like this , you have to isolate the possibilites one by one .

In this blog , I will share what are those checks need to be performed when you are not able to use your system for HVM or full virtualization.

First of all your processor should have support for Virtualization.

This can be checked by below command:

egrep ‘^flags.*(vmx|svm)’ /proc/cpuinfo

[root@humbles-lap ~]# egrep ‘^flags.*(vmx|svm)’ /proc/cpuinfo
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good xtopology nonstop_tsc aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2

[root@humbles-lap ~]#

VMX flag stands for Intel VT and SVM flag stands for AMD-V ..

Now I have confirmed my processor support virtualization.. Still I am not able to use virtualization or still receive error message (“KVM is disabled in BIOS”) in my logs.

The second check should be in BIOS : for “Virtualization” in your BIOS, the name/option may change in BIOS depend on the system. It will be disabled if you noticed above message in the logs. In that case you have to turn it ON or ENABLE it in BIOS.

I enabled it and booted my system , still no luck.. 🙁

After poking some more time I found out that, I have to do “FULL POWER CYCLING” of the system ( POWER OFF, then POWER ON) after enabling Virtualization in BIOS to get it work.

Once I did all these , I was able to load KVM modules and everything worked perfectly and NO errors in logs..