Is it safe to use "raw access"-.vdmk for a VM on the same physical disk as the host?

Question

Main question:

On a dual boot configuration with Ubuntu and Windows 8, can I use a .vdmk with "Raw Access" to the Ubuntu-Partions as a disk image for VirtualBox on Windows safely? (Safe in principle, human errors excluded.)

Why would you want to do this?

The Dual boot with Ubuntu serves two purposes:

1. Checking C++ code I wrote in Visual Studio for compatibility with Linux.
2. Developing a USB-based application on Linux.

For the first purpose a Virtual Machiche is perfect, because I don't have to turn my PC on and off all the time and performance isn't a very huge concern. (I don't care if the compiler takes a minute longer or not.)

But USB-emulation is prone to bugs, and as the application will only run natively, I need the ability to produce accurate benchmarks, so that isn't an option for the second use-case. (I tried it before and it was horrible.)

I could of course just use a pure VM and a seperate physical install of Ubuntu, but as this setup is on a laptop, I am limited to roughly 250GB of total storage, so redundancy of a whole OS is not desired.

Setup:

One physical hard-disk with a total of five partitions and about 250GB of storage:

/dev/sda0: EFI-Boot
/dev/sda1: Ubuntu14.04 ext4, Primary, 30GB
/dev/sda2: Windows8 ntfs, 212GB
/dev/sda3: Windows Recovery
/dev/sda4: swap

Grub2 is used as the bootmanager, not that it really matters.

I now want the ability to Boot directly into Ubuntu if needed, and the ability to boot into Windows to then fire up VirtualBox, which uses the native partions sda1 and sda4 instead of a VDI. So Windows will always be the host.

Answer 1

This should work just fine, as you are not accessing the same device from two places at the same time.

You might need to tweak Ubuntu modules so that it also loads Virtualbox specific drivers during bootup.