28 Sep
2023
28 Sep
'23
4:24 p.m.
On Wed, Sep 27, 2023 at 03:29:35PM +0200, David Hildenbrand wrote:
if (!pte_same(*src_pte, orig_src_pte) ||!pte_same(*dst_pte, orig_dst_pte) ||folio_test_large(src_folio) ||folio_estimated_sharers(src_folio) != 1) {^ here you should check PageAnonExclusive. Please get rid of any implicit explicit/implcit mapcount checks.
David, is PageAnon 100% accurate now in the current tree?
IOW, can it be possible that the page has total_mapcount==1 but missing AnonExclusive bit in any possible way?
Thanks,
--
Peter Xu