Re: [PATCH 1/3] drm/msm: don't clean up priv->kms prematurely

From: Dmitry Baryshkov
Date: Mon Apr 22 2024 - 15:45:09 EST


On Mon, Apr 22, 2024 at 09:12:20AM -0700, Abhinav Kumar wrote:
>
>
> On 4/21/2024 3:35 PM, Dmitry Baryshkov wrote:
> > On Sat, Apr 20, 2024 at 04:02:00PM -0700, Abhinav Kumar wrote:
> > >
> > >
> > > On 4/19/2024 7:33 PM, Dmitry Baryshkov wrote:
> > > > MSM display drivers provide kms structure allocated during probe().
> > > > Don't clean up priv->kms field in case of an error. Otherwise probe
> > > > functions might fail after KMS probe deferral.
> > > >
> > >
> > > So just to understand this more, this will happen when master component
> > > probe (dpu) succeeded but other sub-component probe (dsi) deferred?
> > >
> > > Because if master component probe itself deferred it will allocate priv->kms
> > > again isnt it and we will not even hit here.
> >
> > Master probing succeeds (so priv->kms is set), then kms_init fails at
> > runtime, during binding of the master device. This results in probe
> > deferral from the last component's component_add() function and reprobe
> > attempt when possible (once the next device is added or probed). However
> > as priv->kms is NULL, probe crashes.
> >
>
> Got it, a better commit text would have helped here. Either way,

I'll update the commit text with the text above.

>
> Reviewed-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>

--
With best wishes
Dmitry