AW: Resend [PATCH] kernel/resource.c: invalidate parent when freed resource has childs

[Schmid, Carsten]

> >
> > In theory, child may have siblings. Would it be possible to have several
> > devices under xhci-hcd?
> 
> I'm less interested in the xhci-hcd case - which I certainly *hope* is
> fixed already? - than in "if this happens somewhere else".
> 
> So if we do want to remove the parent (which may be a good idea with a
> warning), and want to make sure that the children are really removed
> from the resource hierarchy, we should do somethiing like
> 
>   static bool detach_children(struct resource *res)
>   {
>         res = res->child;
>         if (!res)
>                 return false;
>         do {
>                 res->parent = NULL;
>                 res = res->sibling;
>         } while (res);
>         return true;
>   }
> 
> and then we could write the __release_region() warning as
> 
>         /* You should not release a resource that has children */
>         WARN_ON_ONCE(detach_children(res));
> 
> or something?
> 
... and a child may have children too ...

There is a __release_child_resources in resource.c around line 242.
A bit noisy, and does a similar thing you outlined above.
I'm thinking about to re-use that, but with more precise output
and WARN_ON_ONCE.

Suggestions before i start work on that?

Best regards
Carsten