I can confirm the suspicion for this issue to relate to Meltdown/Spectre patching.
Running an Ubuntu 16.04 desktop in a virtual machine (VMware Workstation 12.5.9) on top of Windows 7.
The hardware is a Dell T1700 with an i7-4770, and it seems the issue arose after BIOS and Microcode update.
I can confirm the suspicion for this issue to relate to Meltdown/Spectre patching.
Running an Ubuntu 16.04 desktop in a virtual machine (VMware Workstation 12.5.9) on top of Windows 7.
The hardware is a Dell T1700 with an i7-4770, and it seems the issue arose after BIOS and Microcode update.