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charset="us-ascii" X-Rspamd-Queue-Id: 61928A005C X-Rspamd-Server: rspam10 X-Rspam-User: X-Stat-Signature: y5pcydjqp811hos3x9o1wg9njgiqf8mm X-HE-Tag: 1718208153-475144 X-HE-Meta: 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 lylDBpg9 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000066, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Jun 11, 2024, James Houghton wrote: > diff --git a/mm/rmap.c b/mm/rmap.c > index e8fc5ecb59b2..24a3ff639919 100644 > --- a/mm/rmap.c > +++ b/mm/rmap.c > @@ -870,13 +870,10 @@ static bool folio_referenced_one(struct folio *folio, > continue; > } > > - if (pvmw.pte) { > - if (lru_gen_enabled() && > - pte_young(ptep_get(pvmw.pte))) { > - lru_gen_look_around(&pvmw); > + if (lru_gen_enabled() && pvmw.pte) { > + if (lru_gen_look_around(&pvmw)) > referenced++; > - } > - > + } else if (pvmw.pte) { > if (ptep_clear_flush_young_notify(vma, address, > pvmw.pte)) > referenced++; Random question not really related to KVM/secondary MMU participation. AFAICT, the MGLRU approach doesn't flush TLBs after aging pages. How does MGLRU mitigate false negatives on pxx_young() due to the CPU not setting Accessed bits because of stale TLB entries?