Re: [2.6 patch] i386: always use 4k stacks

Adrian Bunk
2005-12-15T22:30:00Z

On Thu, Dec 15, 2005 at 02:00:13PM -0800, Andrew Morton wrote:
> Adrian Bunk <bunk@stusta.de> wrote:
> >
> > This patch was already sent on:
> > - 11 Dec 2005
> > - 5 Dec 2005
> > - 30 Nov 2005
> > - 23 Nov 2005
> > - 14 Nov 2005
>
> Sigh. I saw the volume of email last time and though "gee, glad I wasn't
> cc'ed on that lot".

If you substract the "this breaks my binary-only M$ Windows driver"
emails there's not much volume left.

> Supporting 8k stacks is a small amount of code and nobody has seen a need
> to make changes in there for quite a long time. So there's little cost to
> keeping the existing code.
>
> And the existing code is useful:
>
> a) people can enable it to confirm that their weird crash was due to a
> stack overflow.
>
> b) If I was going to put together a maximally-stable kernel for a
> complex server machine, I'd select 8k stacks. We're still just too
> squeezy, and we've had too many relatively-recent overflows, and there
> are still some really deep callpaths in there.

a1) People turn off 4k stacks and never report the problem / noone
really debugs and fixes the reported problem.

Me threatening people with enabling 4k stacks for everyone already
resulted in several fixes.

An how many weird crashes with _different_ causes have you seen?
It could be that there are only _very_ few problems that noone really
debugs brcause disabling 4k stacks fixes the issue.

cu
Adrian

--

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