Ticket #12649 (closed defect: obsolete)

Opened 7 years ago

Last modified 6 years ago

BMI2 cpuid feature mistakenly enabled in VM

Reported by: Wim Owned by:
Component: other Version: VirtualBox 4.3.6
Keywords: Cc:
Guest type: Linux Host type: Windows


When running VirtualBox on a Haswell i5-3427U, the BMI2 cpuid feature bit is turned on in the VM while it is off on the host. Applications running in the VM therefore think the CPU supports instructions such as SHLX, which it doesn't, and generate illegal instruction traps.

CPU: Intel(R) Core(TM) i5-3427U CPU @ 1.80GHz
Host: Windows 8
VM: Ubuntu 13.10

Change History

comment:1 Changed 7 years ago by frank

I cannot confirm this. Please attach a VBox.log file of such a VM session. And which application did you execute which wrongly assumed that the BMI2 bit is set? Could you also attach the output of

cat /proc/cpuinfo

as well as the output of


executed inside your guest? You might need to install the 'cpuid' package to do so.

comment:2 Changed 6 years ago by frank

  • Status changed from new to closed
  • Resolution set to obsolete
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