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> > > Why is a tlb_remove_table_sync_one() needed in huge_pmd_unshare()? > > > > > > > > Because nothing else on that path is guaranteed to send any IPIs > > > > before the page table becomes reusable in another process. > > > > > > I feel that David's suggestion of just disallowing the use of shared page > > > tables like this (I mean really does it actually come up that much?) is the > > > right one then. > > > > Yeah, I also like that suggestion. > > I started hacking on this (only found a bit of time this week), and in > essence, we'll be using the mmu_gather when unsharing to collect the pages > and handle the TLB flushing etc. > > (TLB flushing in that hugetlb area is a mess) > > It almost looks like a cleanup. > > Having that said, it will take a bit longer to finish it and, of course, I > first have to test it then to see if it even works. > > But it looks doable. :) Ohhhh nice :) I look forward to it! > > -- > Cheers > > David / dhildenb > Cheers, Lorenzo