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Is > > > xen_released_pages expected to be non-zero for a domU? > > > > Oh, yes. In fact I think the patch here is wrong for PV dom0, as it > > shouldn't subtract xen_released_pages from xen_start_info->nr_pages. > > I will need to send v2. > > To be clear, the numbers and warning are from the follow on > current_reservation patch. Yes, but I think it's also bad to use xen_start_info->nr_pages - xen_released_pages (my current proposal). xen_released_pages had a different meaning on PV which I kind of stolen for the unpopulated alloc work. It was originally meant to signal pages that are freed during the boot process when it's not possible to relocate them; see xen_set_identity_and_release_chunk. Unpopulated alloc doesn't free the pages it uses, because they are already free to start with. I think I need to introduce a new counter that accounts for pages consumed by unpopulated alloc strictly, and not re-use the xen_released_pages counter. All this memory accounting is far more complex than it should be sadly. Thanks, Roger.