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See http://www.infradead.org/rpr.html X-Stat-Signature: o3c3dideojxhy7rmezs59y6nhsjskeuu X-Rspamd-Queue-Id: 1749D100013 X-Rspam-User: X-Rspamd-Server: rspam10 X-HE-Tag: 1730262763-746014 X-HE-Meta: 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 6QmYc+LL 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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, Oct 29, 2024 at 09:30:41PM -0700, John Hubbard wrote: > I do, yes. And what happens is that when you use GPUs, drivers like > to pin system memory, and then point the GPU page tables to that > memory. For older GPUs that don't support replayable page faults, > that's required. > > So this behavior has been around forever. > > The customer was qualifying their software and noticed that before > Linux 6.10, they could allocate >2GB, and with 6.11, they could > not. > > Whether it is "wise" for user space to allocate that much at once > is a reasonable question, but at least one place is (or was!) doing > it. Still missing a callchain, which make me suspect that it is your weird out of tree driver, in which case this simply does not matter.