Re: [PATCH 4/7] phy: rockchip-usb: add missing of_node_put
From: Heiko Stübner
Date: Wed Nov 18 2015 - 15:40:46 EST
Hi Julia,
Am Mittwoch, 18. November 2015, 21:38:02 schrieb Julia Lawall:
> On Wed, 18 Nov 2015, Heiko Stübner wrote:
> > Am Mittwoch, 18. November 2015, 11:31:29 schrieb Brian Norris:
> > > On Wed, Nov 18, 2015 at 08:27:07PM +0100, Heiko Stübner wrote:
> > > > Am Montag, 16. November 2015, 12:33:17 schrieb Julia Lawall:
> > > > hmm, while I agree that the rockchip phy has an issue in the node
> > > > lifecycle, I'm not sure that patch fixes it fully.
> > > >
> > > > It currently iterates over each phy, but would only of_node_put the
> > > > phy it
> > > > handled last. So if an error happens on the 3rd phy, the first 2 are
> > > > already instantiated and would also get removed when the overall probe
> > > > fails, but their of_node would never be "put".
> > >
> > > Note the behavior of of_get_next_child() (and
> > > of_get_next_available_child()); it "Decrements the refcount of prev." So
> > > the loop only keeps a reference for (at most) one node at a time.
> > >
> > > I believe Julia's patch is correct. It's possible the commit description
> > > could have made this aspect clearer though, since I was confused about
> > > this at first as well.
> >
> > oh, I hadn't realized that :-) .
> >
> > Although in this case, what happens with the last child, if only "prev"s
> > get decremented? When the loop finished I'd think that the last one would
> > keep it's reference, as the patch stand right - or I'm just blind.
>
> The loop finishes when the child is NULL. So there is nothing to put in
> that case. The process of getting from the last child to the NULL does
> the of_node_put.
sorry for being a bit slow today ... I should probably sleep more :-)
Then the patch looks fine ... I'll add my Tag on the top, to not burry it down
here.
Heiko
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