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charset=utf-8 Content-Disposition: inline X-Stat-Signature: jmwirnjhdrh1dhm9jenseqkrrhd6ejqd X-Rspam-User: X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 5FBB3140006 X-HE-Tag: 1766157217-414511 X-HE-Meta: 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 /fbFJJAn 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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 Fri, Dec 19, 2025 at 10:59:57AM -0400, Jason Gunthorpe wrote: > On Tue, Dec 16, 2025 at 02:44:29PM -0500, Peter Xu wrote: > > > > Or maybe I misunderstood what you're suggesting to document? If so, please > > > > let me know; some example would be greatly helpful. > > > > > > Just document the 'VA % order = pgoff % order' equation in the kdoc > > > for the new op. > > > > When it's "related to PTEs", it's talking about (2) above, so that's really > > what I want to avoid mentioning. > > You can't avoid it. Drivers must ensure that > > pgoff % order == physical % order > > And that is something only drivers can do by knowing about this > requirement. This is a current limitation that above must be guaranteed, there's not much the driver can do, IMHO. If you could remember, that's the only reason why I used to suggest (while we were discussing this in v1) to make it *pgoff instead of pgoff, so that drivers can change *pgoff to make it relevant to HPA. I didn't take that approach as I want to make this simple until it's justified to be required. It holds true for vfio-pci, I hope it holds true forever. If not, this API will stop working, afaict. -- Peter Xu