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Maybe this can be expanded later to be automatic. But I think it >> simpler to start with explicit user input. > > I guarantee virtually nobody will ever use an explicit kernel interface > to bump the size up. It'll be the same exact folks that recompile their > kernels. Right, I agree. My intent was to help avoid a recompile if, for example, the config size was not enough. Meaning even if a fleet has a custom kernel with 8 pages of size, it may happen that more is needed. But "may happen" isn't a strong reason to make a change here. :) > > An automatic resizing one doesn't have to be fancy and only has to > expand once: > Why once? > static bool expanded = false; > > ... > > if (full && !expanded) { > expand(); > expanded = true; > } > > It might be a _wee_ bit worse than that because you might have to queue > some work outside of #MC context but seriously we're talking 10-ish > lines of code. It'd probably be even smaller than doing it when poked > by userspace and wouldn't involve new ABI. Okay, I'm with you here. Thanks, Yazen