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Shutemov" Cc: Jann Horn , Andrew Morton , linux-mm@kvack.org, "Kirill A. Shutemov" , "Zach O'Keefe" , linux-kernel@vger.kernel.org, David Hildenbrand Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: D1834A001B X-Stat-Signature: red6xhzft1qbcxco3pcydnnjy4mudsau X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1673981879-585541 X-HE-Meta: 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 zYydp/IZ 5y9aI3mOlPK09Wsdo7049933twIvNjPz+SHTDEFA6tA7nNdnhuT/R8rDjXhsB1iiY5qzOPFwCEyP8ToI2CjNSYewSzbJkO5Kq1j1t 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 Sun, Jan 15, 2023 at 11:07 AM Kirill A. Shutemov wrote: > > On Fri, Jan 13, 2023 at 08:28:59PM +0100, Jann Horn wrote: > > No, that lockdep assert has to be there. Page table traversal is > > allowed under any one of the mmap lock, the anon_vma lock (if the VMA > > is associated with an anon_vma), and the mapping lock (if the VMA is > > associated with a mapping); and so to be able to remove page tables, > > we must hold all three of them. > > Okay, that's fair. I agree with the patch now. Maybe adjust the commit > message a bit? Yeah, the explanation makes sense to me too. Reviewed-by: Yang Shi > > Anyway: > > Acked-by: Kirill A. Shutemov > > BTW, I've noticied that you recently added tlb_remove_table_sync_one(). > I'm not sure why it is needed. Why IPI in pmdp_collapse_flush() in not > good enough to serialize against GUP fast? > > -- > Kiryl Shutsemau / Kirill A. Shutemov