Re: [git patch] free_irq() fixes

[Linus Torvalds <torvalds@linux-foundation.org>]

On Wed, 23 Apr 2008, Jeff Garzik wrote:
> 
> When drivers make assumptions about system irq numbering, particularly on x86,
> IMO the situation is fragile.

And when people make changes to long-standing and stable infrastructure, 
the situation also gets fragile.

The fact is, stability of interfaces is a really worthy goal in itself. 
Making a change for its own sake is not a good thing. This fixes 
*nothing*, and the driver changes I objected to I objected to because they 
were ugly as sin.

And I want to point out that your patches made it *much* uglier.

So "cleanup" it sure as hell wasn't. That irq number may not be worth all 
that much in itself, but it has no subtle implementation problems (we 
_need_ that irq number for registration and irq handler lookup anyway, so 
it is meaningful from a driver perspective, and is well-defined from a irq 
core standpoint as well).

I don't mind cleanups, but this is "churn". Change for its own sake. If it 
doesn't lead to any _improvement_, it's pointless.

If drivers don't need it, let them ignore it. But let them ignore it in 
ways that work across versions, and in ways that don't cause ridiculous 
and ugly work-arounds for when they do want it (even if it's just for a 
printk() or similar).

		Linus