On 13/02/21 01:50, Sean Christopherson wrote:
This means that spurious PML entries will be created for memslots with dirty logging disabled if at least one other memslot has dirty logging enabled, but for all known use cases, dirty logging is a global VMM control.
This is not true. For example QEMU uses dirty logging to track changes to the framebuffer.
However, what you're saying below is true: after a MR_CREATE there will be no shadow pages, and when they are created with mmu_set_spte they will not have the dirty bits set. So there's really no change here for the case of only some memslots having dirty logging enabled. Queued 12 and 13 as well then!
Paolo
Furthermore, spurious PML entries are already possible since dirty bits are set only when a dirty logging is turned off, i.e. memslots that are never dirty logged will have dirty bits cleared.
