Re: [PATCH] USB: cdc-acm: fix broken runtime suspend

From: Greg Kroah-Hartman
Date: Sat May 24 2014 - 15:59:29 EST


On Sat, May 24, 2014 at 04:42:42PM +0200, Johan Hovold wrote:
> On Mon, Apr 14, 2014 at 09:58:12PM +0200, Johan Hovold wrote:
> > The current ACM runtime-suspend implementation is broken in several
> > ways:
> >
> > Firstly, it buffers only the first write request being made while
> > suspended -- any further writes are silently dropped.
> >
> > Secondly, writes being dropped also leak write urbs, which are never
> > reclaimed (until the device is unbound).
> >
> > Thirdly, even the single buffered write is not cleared at shutdown
> > (which may happen before the device is resumed), something which can
> > lead to another urb leak as well as a PM usage-counter leak.
> >
> > Fix this by implementing a delayed-write queue using urb anchors and
> > making sure to discard the queue properly at shutdown.
> >
> > Reported-by: Xiao Jin <jin.xiao@xxxxxxxxx>
> > Signed-off-by: Johan Hovold <jhovold@xxxxxxxxx>
>
> Greg,
>
> I understand youÍ're on your way home from Japan and are getting ready to
> work through the 3.16 patch queue.
>
> Could you please discard this one for now? I've found a couple of more
> PM related problems and I'll submit a slight update of this one as part
> of a larger series of fixes instead.

I think it's already in my tree, right? I don't see it in my to-apply
queue. Can you send me the git id to revert, or just a patch that
reverts it?

thanks,

greg k-h
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