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Yes, I understand you concerns with struct page from past abuses. > The struct page based approach in fundamentally incompatible with > driver managed exporters. The *general* struct page system is incompatible - but that is not what I'm suggesting. I'm suggesting io_uring, and only io_uring could use this with it fully implementing all the lifecycle rules that are needed. Including move_notify and fences so that the driver managed exporter has no issue. Reworking the block stack to not rely on page is also a good path, but probably alot harder. :\ Jason