Re: [PATCH] drm/msm/dp: move link_ready out of HPD event thread

From: Johan Hovold
Date: Tue Mar 12 2024 - 12:41:27 EST


On Tue, Mar 12, 2024 at 11:09:11AM +0100, Johan Hovold wrote:
> On Fri, Mar 08, 2024 at 01:45:32PM -0800, Abhinav Kumar wrote:

> > @@ -466,6 +466,8 @@ static int dp_display_notify_disconnect(struct device *dev)
> > {
> > struct dp_display_private *dp = dev_get_dp_display_private(dev);
> >
> > + dp->dp_display.link_ready = false;
>
> As I also pointed out in the other thread, setting link_ready to false
> here means that any spurious connect event (during physical disconnect)
> will always be processed, something which can currently lead to a leaked
> runtime pm reference.
>
> Wasting some power is of course preferred over crashing the machine, but
> please take it into consideration anyway.
>
> Especially if your intention with this patch was to address the resets
> we saw with sc8280xp which are gone since the HPD notify revert (which
> fixed the hotplug detect issue that left the bridge in a
> half-initialised state).

Heh. This is getting ridiculous. I just tried running with this patch
and it again breaks hotplug detect in a VT console and in X (where I
could enable a reconnected external display by running xrandr twice
before).

So, please, do not apply this one.

Johan