Re: [PATCH] x86-32: always use irq stacks

[Christoph Hellwig]

On Wed, May 26, 2010 at 02:47:07PM +0200, Thomas Gleixner wrote:
> On Wed, 26 May 2010, Christoph Hellwig wrote:
> 
> > 
> > IRQ stacks provide much better safety against unexpected stack use from
> > interrupts, at the minimal downside of slightly higher memory usage.
> > Enable irq stacks also for the default 8k stack to minimize the problem
> > of stack overflows through interrupt activity.
> > 
> > This is what x86-64 and various other architectures already do.
> 
> We got rid of nested interrupts, so is this really a concern anymore ?

Yes, especially for deep storage stacks anything that can come in
unexpectedly from IRQ context is quite harmful.  It's a really cheap
way to avoid that indeterminism.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/