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charset="UTF-8" X-Rspamd-Queue-Id: 655FA4000F X-Stat-Signature: rr5gzscxc1mn758yye5xnhraek1nd48o X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1674065381-643947 X-HE-Meta: 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 FzRG4c/B qJn1Fc+SBdUMddSzP86sjpecsYFapE8XLCOZJlnzW7R7fX1bAkfSxMQyirQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Jan 18, 2023 at 1:23 AM Michal Hocko wrote: > > On Tue 17-01-23 18:01:01, Suren Baghdasaryan wrote: > > On Tue, Jan 17, 2023 at 7:16 AM Michal Hocko wrote: > > > > > > On Mon 09-01-23 12:53:12, Suren Baghdasaryan wrote: > > > > Move VMA flag modification (which now implies VMA locking) before > > > > anon_vma_lock_write to match the locking order of page fault handler. > > > > > > Does this changelog assumes per vma locking in the #PF? > > > > Hmm, you are right. Page fault handlers do not use per-vma locks yet > > but the changelog already talks about that. Maybe I should change it > > to simply: > > ``` > > Move VMA flag modification (which now implies VMA locking) before > > vma_adjust_trans_huge() to ensure the modifications are done after VMA > > has been locked. > > Because .... because vma_adjust_trans_huge() modifies the VMA and such modifications should be done under VMA write-lock protection. > > Withtout that additional reasonaning it is not really clear why that is > needed and seems arbitrary. Would the above be a good reasoning? > > -- > Michal Hocko > SUSE Labs