On Wed, 14 May 2008, Alan Cox wrote:
>
> Here is a fun one for general discussion - right now driver probe
> functions request resources. We have no ordering on the requests so we
> have deadlocks if two drivers do resource requests for conflicting
> resources in reverse order.

resource requests aren't blocking, so it wouldn't actually be a deadlock.
It would just be a "both failed, try again".

That said, two drivers shouldn't be probing the same hardware at the same
time regardless, so I can't imagine that it's much of a problem in real
life.

Linus
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Alan Cox writes:

> Out of amusement I took the watchdog drivers and started looking for
> large cans of worms in the BKL drop arena.
>
> Here is a fun one for general discussion - right now driver probe
> functions request resources. We have no ordering on the requests so we
> have deadlocks if two drivers do resource requests for conflicting
> resources in reverse order.

What deadlocks? resource allocation normally doesn't block. So if there's
a ordering issue one of them will fail and should bail out.

That said if you have conflicting resources then failing is the correct
behavior anyways.

-Andi
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