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Failing to pin a single > > page is always an error, the only question is what sub reason caused > > the error to happen. There is no third case where it is not an error. > > The uprobe path thinks otherwise, but maybe the answer is that we just need > to -EFAULT on missing VMA and -EPERM on invalid flags. I think uprobe is just broken to think there is a third outcome. Let's just fix it instead of trying to pretend it makes sense. Jason