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Subject: Re: Can we move device drivers into user-space?
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From: Theodore Tso <tytso@MIT.EDU>
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Cc: Theodore Tso <tytso@MIT.EDU>, Greg KH <gregkh@linuxfoundation.org>,
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To: "Henrik Rydberg" <rydberg@euromail.se>
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On Feb 24, 2012, at 5:14 PM, Henrik Rydberg wrote:

> True, and the emergent interface (vfs) is even accessible in
> userspace, so all is good in that department for now. Conversely, you
> have not shown that this can go on forever. ;-)

… and the performance is terrible --- as it must be.  If you don't understand why this must be, then we're wasting our time having this conversation.

And if you're the one wanting to make a change, then you are the one who has to provide the proof.   Otherwise we're just talking about hypotheticals, and that way lies over-design.  Why waste time engineering something that may never come to pass?

Of course, your time is something you are free to spend however you like.  So if you want to try implementing some of these grand plans of yours, show us the code….

-- Ted