Using the KVM API

> They are needed for unrestricted_guest=0. Remember that, in that case, the VM always runs in protected mode and with paging enabled. In order to emulate real mode you put the guest in a vm86 task, so you need some place for a TSS and for a page table, and they must be in guest RAM because the guest's TR and CR3 points to it.

Ah, I see.

> If you don't call KVM_SET_TSS_ADDR you actually get a complaint in dmesg, and the TR stays at 0.

While I saw the mention of that message in a few places, I don't actually get that message at any point. Presumably that only happens with unrestricted_guest=0?

Please consider documenting the use of these two ioctls and the data they point to, as well as what circumstances require them; the current KVM documentation doesn't mention any of that.