H. Peter Anvin wrote:The fixmap area should never have been made movable. It's utter braindamage.
Shrug. It's been like that for a couple of years now. It was one of the very first paravirt-ops patches. It wasn't controversial then, and nobody seems to have noticed since.
Given the x86 architecture, it's inevitable that PV will want to reserve address space at the top of memory, and therefore the fixmap area needs to be moved out of that space.
OK. But there's a few places where the code uses FIXADDR_TOP to mean "top of kernel address space", so we'd need to come up with a proper symbol for that.