Re: [RFC] mlock/stack guard interaction fixup

Peter Zijlstra
2010-08-23T09:22:44Z

On Sun, 2010-08-22 at 11:21 -0700, Linus Torvalds wrote:
> Doing hypercalls from user space on stuff that is on the stack,
> rather than just copying it to some stable area is dodgy. And I
> guarantee that doing the crazy mlock dance is slower than the copy, so
> it's complex, fragile, _and_ slow.
>
That sounds broken too, not having read the initial problem and such, it
sounds like the hypercall would expect the pages to stay pinned and
mlock doesn't actually guarantee that at all.