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Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , "Matthew Wilcox (Oracle)" , Wei Yang , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, stable@vger.kernel.org, Pankaj Raghav Subject: Re: [PATCH v3] mm/huge_memory: do not change split_huge_page*() target order silently. 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Commit e220917fa507 ("mm: split= a >> folio in minimum folio order chunks") bumps the target order of >> split_huge_page*() to the minimum allowed order when splitting a LBS fol= io. >> This causes confusion for some split_huge_page*() callers like memory >> failure handling code, since they expect after-split folios all have >> order-0 when split succeeds but in reality get min_order_for_split() ord= er >> folios and give warnings. >> >> Fix it by failing a split if the folio cannot be split to the target ord= er. >> Rename try_folio_split() to try_folio_split_to_order() to reflect the ad= ded >> new_order parameter. Remove its unused list parameter. >> >> Fixes: e220917fa507 ("mm: split a folio in minimum folio order chunks") >> [The test poisons LBS folios, which cannot be split to order-0 folios, a= nd >> also tries to poison all memory. The non split LBS folios take more memo= ry >> than the test anticipated, leading to OOM. The patch fixed the kernel >> warning and the test needs some change to avoid OOM.] >> Reported-by: syzbot+e6367ea2fdab6ed46056@syzkaller.appspotmail.com >> Closes: https://lore.kernel.org/all/68d2c943.a70a0220.1b52b.02b3.GAE@goo= gle.com/ >> Cc: stable@vger.kernel.org >> Signed-off-by: Zi Yan >> Reviewed-by: Luis Chamberlain >> Reviewed-by: Pankaj Raghav >> Reviewed-by: Wei Yang >> --- > > With Lorenzos comments addressed, this looks good to me, thanks for takin= g care of this! Just to be clear, I do not need to respin a new version of this, since all Lorenzo=E2=80=99s comments are addressed in my reply except the changelog o= ne, right? > > Acked-by: David Hildenbrand > > --=20 > Cheers > > David / dhildenb Best Regards, Yan, Zi