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David Alan Gilbert" , "Matthew Wilcox (Oracle)" , Vlastimil Babka , Baolin Wang , Miaohe Lin , Yang Shi , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" X-Stat-Signature: wb7hummmz9kxiy9a1ewzykoyhoms1hcr X-Rspam-User: X-Rspamd-Queue-Id: E6156180017 X-Rspamd-Server: rspam06 X-HE-Tag: 1672159124-872417 X-HE-Meta: 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 FJLAZyvm McA9iJtL93LteAgJQ2BFIPPVa7zPNc0lrg0/hrNvz562dWJ1j2t+8uZrdwQ== 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 Fri, Dec 23, 2022 at 1:38 PM Peter Xu wrote: > > James, > > On Fri, Oct 21, 2022 at 04:36:50PM +0000, James Houghton wrote: > > + bool use_hgm = uffd_ctx_has_hgm(&dst_vma->vm_userfaultfd_ctx) && > > + mode == MCOPY_ATOMIC_CONTINUE; > > Do you think in your new version use_hgm can work even for MISSING by > default? I don't think so -- UFFDIO_COPY will allocate a hugepage, so I'm not sure if it makes sense to allow it at high-granularity. If UFFDIO_COPY didn't allocate a new page, then it could make sense (maybe we'd need a new ioctl or new UFFDIO_COPY mode?). I think it makes most sense to add this with another series. Thanks, - James