How would one test for, StackSize=4k

[T. 'Nifty New Hat' Mitchell]

On Tue, Jun 15, 2004 at 11:49:45AM +0100, Dave Jones wrote:
> From: Dave Jones <davej at redhat.com>
> To: For users of Fedora Core releases <fedora-list at redhat.com>
> Date: Tue, 15 Jun 2004 11:49:45 +0100
> Subject: Re: How would one test for, StackSize=4k
> Reply-To: For users of Fedora Core releases <fedora-list at redhat.com>
> 
> On Mon, 2004-06-14 at 23:20, T. 'Nifty New Hat' Mitchell wrote:
> > The 4K stack size seems to be part of the future.
> > 
> > As the transition progresses, how would one test for StackSize=4k?
> > Both in make/config  files and in install scripts where two object
> > (4k or 8K) could be installed.
> > 
> > Also is it possible to build a set of  wrappers that do the right 
> > thing into and out of a driver when the driver and kernel ABI
> > do not match on this choice.
> 
> If you fix the code so that it works with a 4K stack, it'll
> work fine with an 8KB one too.  I can't actually think of a
> valid reason for a module wanting to detect which is in use.


Thanks Dave, 

I had not thought about it from that side of the room.  It makes sense
that if you can manage to live with a 4K stack an extra 4K would not
cause harm with the possible exception of memory allocation bugs
(leak/free).

The reverse is not true.

For a second or two I wondered if knowing the stack size would be
valuable for an install script to check and not load 8K stack code.
However, anyone reworking things to add such a test might as well do
the right thing and recompile/adjust for 4K stacks.

I suspect that there are still some folks working on new kernel stuff
with 8K stacks active on their systems some caution on this topic will
continue....


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