Re: [patch 0/5] Support for sanitization flag in low-level page allocator

Alan Cox
2009-05-28T06:26:00Z

> > As for being swapped out - I do not believe that kernel stacks can
> > ever be swapped out in Linux.
>
> yes, i referred to that as an undesirable option - because it slows
> down pthread_create() quite substantially.
>
> This needs before/after pthread_create() benchmark results.

kernel stacks can end up places you don't expect on hypervisor based
systems.

In most respects the benchmarks are pretty irrelevant - wiping stuff has
a performance cost, but its the sort of thing you only want to do when
you have a security requirement that needs it. At that point the
performance is secondary.

Alan