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charset="UTF-8" X-Rspamd-Queue-Id: D436A180002 X-Stat-Signature: cu5texeqwmri57gsdcjm99jpdxbt8cdy X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1674078505-644628 X-HE-Meta: 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 2f3JtFjc ob+VQb+YlIBd66XO87efTqNUrkMxeErYI9IYaqHPqw54ifvPUPYerWuHlaQ== 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 1:33 PM Michal Hocko wrote: > > On Wed 18-01-23 10:09:29, Suren Baghdasaryan wrote: > > 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. > > So it will become: > 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 vma_adjust_trans_huge() modifies the VMA and such > modifications should be done under VMA write-lock protection. > > which is effectivelly saying > vma_adjust_trans_huge() modifies the VMA and such modifications should > be done under VMA write-lock protection so move VMA flag modifications > before so all of them are covered by the same write protection. > > right? Yes, and the wording in the latter version is simpler to understand IMO, so I would like to adopt it. Do you agree? > -- > Michal Hocko > SUSE Labs