Re: [PATCH 0/6] driver core: Fix some issues related to device links

From: Rafael J. Wysocki
Date: Thu Jan 24 2019 - 18:08:37 EST


On Thu, Jan 24, 2019 at 3:58 PM Russell King - ARM Linux admin
<linux@xxxxxxxxxxxxxxx> wrote:
>
> On Thu, Jan 24, 2019 at 12:13:06PM +0100, Rafael J. Wysocki wrote:
> > Hi Greg at al,
> >
> > Recently I have been looking at the device links code because of the
> > recent discussion on possibly using them in the DRM subsystem (see for
> > example https://marc.info/?l=linux-pm&m=154832771905309&w=2) and I have
> > found a few issues in that code which should be addressed by this patch
> > series. Please refer to the patch changelogs for details.
> >
> > None of the problems addressed here should be manifesting themselves in
> > mainline kernel today, but if there are more device links users in the
> > future, they most likely will be encountered sooner or later. Also they
> > need to be fixed for the DRM use case to be supported IMO.
> >
> > This series does not fix all issues in device links that have become
> > apparent (generally speaking, the idea of returning an existing link
> > in case there is one already for the given consumer-supplier pair
> > doesn't play well with stateful links and their flags), so there will
> > be a follow-up series of patches to clean that up. Still, I don't see
> > a reason to sit on these fixes while working on the other patches, so
> > here they go.
>
> Hi Rafael,
>
> I've just given these a quick boot, unbind and rebind test with my
> DRM case, and nothing seems to have regressed on the face of it.
>
> Tested-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxx>

Thank you!