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SubjectRe: Address translation
From said:
> Does anybody know a function or method in order to translate an user
> space pointer into a valid pointer in kernel mode?

> I'd like to avoid copying data (such as the 'copy_to_user' and
> 'copy_from_user' functions do) because it slows down my system.

The reason that everyone else uses copy_{to,from}_user is that there is no way
to guarantee that the userspace pointer is valid. That memory may have been
swapped out. The copy macros are prepared to fault the memory in. The rest
of the kernel is not.


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