Pass the smelling salts. Microsoft Monday released 20,000 lines of device driver code to the Linux community under the GPL 2 license, the mother of all open source licenses written when open source was still a pup by the brassbound Free Software Foundation.

The company itself admits the shock, horror move “would have been unheard of from Microsoft a few years ago” and puts it down to customer demand.

According to Tom Hanrahan, director of Microsoft’s Open Source Technology Center, “Customers have told us that they would like to standardize on one virtualization platform, and the Linux device drivers will help customers who are running Linux to consolidate their Linux and Windows servers on a single virtualization platform, thereby reducing the complexity of their infrastructure.”

In other words, Microsoft is sacrificing its religious convictions to its pocketbook. (Pshew, no apostasy there then.)

The recession, tight customer budgets, hardware consolidation and the realization that reduced complexity translates into reduced cost is forcing Microsoft to be more amenable.

According to Sam Ramji, senior director of Microsoft’s platform strategy, “We are seeing interoperability as a lever for business growth.”

The code, which includes three Linux device drivers, has been submitted to the Linux kernel community for inclusion in the Linux tree.

That’s another first. Microsoft has never released code directly to the Linux community before.

The drivers will be available to both the community and customers, and are supposed to enhance Linux’ performance when virtualized on Windows Server 2008 Hyper-V or Windows Server 2008 R2 Hyper-V.

Hanrahan says, “Our initial goal in developing the code was to enable Linux to run as a virtual machine on top of Hyper-V…The Linux device drivers we are releasing are designed so Linux can run in enlightened mode, giving it the same optimized synthetic devices as a Windows virtual machine running on top of Hyper-V. Without this driver code, Linux can run on top of Windows, but without the same high performance levels.”

In a prepared pitch, Ramji suggests that Microsoft going forward means to make increased “use of ‘inbound’ open source and the open source development model to make our software development processes more efficient” and “to reduce marketing and sales costs or to try out new features that highlight parts of the platform customers haven’t seen before.”

See here.