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See http://www.infradead.org/rpr.html X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: DE175180003 X-Stat-Signature: uya98xtn8xdiqpb8ay4xjz458y9eck9d X-HE-Tag: 1741758449-308681 X-HE-Meta: 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 LtI8qdsP 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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, Mar 11, 2025 at 11:15:11AM +0100, Jakub Kicinski wrote: > On Mon, 10 Mar 2025 14:35:24 +0000 Matthew Wilcox (Oracle) wrote: > > Long-term, networking needs to stop taking a refcount on the pages that > > it uses and rely on the caller to hold whatever references are necessary > > to make the memory stable. > > TBH I'm not clear on who is going to fix this. > IIRC we already told NVMe people that sending slab memory over sendpage > is not well supported. Plus the bug is in BPF integration, judging by > the stack traces (skmsg is a BPF thing). Joy. slab over sendpage doesn't work because you refuse to take the patches to make it work by transparently falling back to sendmsg. It's a giant pain for all network storage drivers caused by the networking maintainers. The ultimate root cause is the fact that networking messes with the refcounts.