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Wong" , SHAURYA RANE , akpm@linux-foundation.org, shakeel.butt@linux.dev, eddyz87@gmail.com, andrii@kernel.org, ast@kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-kernel-mentees@lists.linux.dev, skhan@linuxfoundation.org, david.hunter.linux@gmail.com, khalid@kernel.org, syzbot+09b7d050e4806540153d@syzkaller.appspotmail.com, bpf Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Server: rspam12 X-Rspam-User: X-Rspamd-Queue-Id: B39B540009 X-Stat-Signature: muzcf3zem7h4jhpk8of7qud3fmz5osdn X-HE-Tag: 1763572346-905006 X-HE-Meta: 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 S0karPYX 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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, Nov 18, 2025 at 9:50=E2=80=AFPM Christoph Hellwig wrote: > > On Tue, Nov 18, 2025 at 11:27:47AM -0800, Andrii Nakryiko wrote: > > Then please help make it better, give us interfaces you think are > > appropriate. People do use this functionality in production, it's > > important and we are not going to drop it. In non-sleepable mode it's > > best-effort, if the requested part of the file is paged in, we'll > > successfully read data (such as ELF's build ID), and if not, we'll > > report that to the BPF program as -EFAULT. In sleepable mode, we'll > > wait for that part of the file to be paged in before proceeding. > > PROCMAP_QUERY ioctl() is always in sleepable mode, so it will wait for > > file data to be read. > > That's pretty demanding: "If you don't give me the interface that I want > I'll just poke into internals and do broken shit" isn't really the > best way to make friends and win influence., Did you read the second part of my reply? The functionality in question ([0]) was developed in the open, over multiple revisions, with both mm and fsdevel mailing list CC'ed. Matthew Wilcox did look at this, provided feedback and suggestion to use filemap_get_folio() + read_cache_folio(), which I did incorporate. [0] https://lore.kernel.org/bpf/20240829174232.3133883-1-andrii@kernel.or= g/ > > > If you don't like the implementation, please help improve it, don't > > just request dropping it "because BPF folks" or anything like that. > > Again, you're trying to put a lot of work you should have done on > others. Everyone here is pretty helpful guiding when asking for help, > but being asked at gunpoint to cleanup the mess your created is not > going to get everyone drop their work and jump onto your project. Gunpoint, really?.. Am I not asking for help to improve the code? This functionality is being used, and we can't "just rip it out" as you propose. Let's fix it instead.