Paolo Bonzini noticed something a little awkward in the Linux kernel support code for Microsoft's HyperV virtualisation environment - specifically, that the magic constant passed through to the hypervisor was "0xB16B00B5", or, in English, "BIG BOOBS". It turns out that this isn't an exception - when the code was originally submitted it also contained "0x0B00B135". That one got removed when the Xen support code was ripped out.At the most basic level it's just straightforward childish humour, and the use of vaguely-English strings in magic hex constants is hardly uncommon. But it's also specifically male childish humour. Puerile sniggering at breasts contributes to the continuing impression that software development is a boys club where girls aren't welcome. It's especially irritating in this case because Azure may depend on this constant, so changing it will break things.
So, full marks, Microsoft. You've managed to make the kernel more offensive to half the population and you've made it awkward for us to rectify it.