> > Hmm, so a new slot->arch.page_attr array shouldn't be necessary, KVM can instead > > update slot->arch.lpage_info on shared<->private conversions. Detecting whether > > a given range is partially mapped could get nasty if KVM defers tracking to the > > backing store, but if KVM itself does the tracking as was previously suggested[*], > > then updating lpage_info should be relatively straightfoward, e.g. use > > xa_for_each_range() to see if a given 2mb/1gb range is completely covered (fully > > shared) or not covered at all (fully private). > > > > [*] https://lore.kernel.org/all/YofeZps9YXgtP3f1@xxxxxxxxxx > > Yes, slot->arch.page_attr was introduced to help identify whether a page > is completely shared/private at given level. It seems XARRAY can serve > the same purpose, though I know nothing about it. Looking forward to > seeing the patch of using XARRAY. > > yes, update slot->arch.lpage_info is good to utilize the existing logic > and Isaku has applied it to slot->arch.lpage_info for 2MB support patches. Chao, are you planning to implement these changes to ensure proper handling of hugepages partially mapped as private/shared in subsequent versions of this series? Or is this something left to be handled by the architecture specific code? Regards, Vishal
