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charset=utf-8 Content-Disposition: inline X-Rspam-User: X-Rspamd-Queue-Id: 6DE97C0012 X-Rspamd-Server: rspam10 X-Stat-Signature: yc1juoz5sd1e4ihgtgbz1iyyyfp77gwn X-HE-Tag: 1750777432-788238 X-HE-Meta: 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 ZBYQKM5c 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 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: List-Subscribe: List-Unsubscribe: On Tue, Jun 24, 2025 at 01:48:50PM +0200, David Hildenbrand wrote: > The man page was updated with > > commit db3d5cc1a17b0ace008ebe1eaf0ac4d96b4b519a > Author: Axel Rasmussen > Date: Tue Oct 3 12:45:44 2023 -0700 > > ioctl_userfaultfd.2: Correct and update UFFDIO_API ioctl error codes > First, it is not correct that repeated UFFDIO_API calls result in > EINVAL. This is true *if both calls enable features*, but in the case > where we're doing a two-step feature detection handshake, the kernel > explicitly expects 2 calls (one with no features set). So, correct this > description. > Then, some new error cases have been added to the kernel recently, and > the man page wasn't updated to note these. So, add in descriptions of > these new error cases. > > @Axel, did you ignore the automatically-set UFFD_FEATURE_INITIALIZED and the > repeated calls never worked, or was there actually a time where repeated > UFFDIO_API calls would not result in EINVAL? The man-pages was inaccurate before. It got updated recently after Kyle asking similar questions, see: http://www.alejandro-colomar.es/src/alx/linux/man-pages/man-pages.git/commit/?id=6a949e9b08fd1ad4e77584276b9566e45fc07a93 Li's v2 change on using the temp fd looks correct. Thanks, -- Peter Xu