Re: [PATCH v2] drm/msm/dp: remove fail safe mode related code

[Abhinav Kumar]

On 4/25/2022 11:00 PM, Stephen Boyd wrote:
> Quoting Kuogee Hsieh (2022-04-25 22:56:35)
> > Current DP driver implementation has adding safe mode done at
> > dp_hpd_plug_handle() which is expected to be executed under event
> > thread context.
> >
> > However there is possible circular locking happen (see blow stack trace)
> > after edp driver call dp_hpd_plug_handle() from dp_bridge_enable() which
> > is executed under drm_thread context.
> >
> > After review all possibilities methods and as discussed on
> > https://patchwork.freedesktop.org/patch/483155/, supporting EDID
> > compliance tests in the driver is quite hacky. As seen with other
> > vendor drivers, supporting these will be much easier with IGT. Hence
> > removing all the related fail safe code for it so that no possibility
> > of circular lock will happen.
> [...]
> > Changes in v2:
> > -- re text commit title
> > -- remove all fail safe mode
> >
> > Signed-off-by: Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx>
>
> Should add some Fixes tags here, probably for the first introduction of
> this logic and the one that moved stuff around to try to avoid the
> lockdep warning.

Fixes: 8b2c181 ("drm/msm/dp: add fail safe mode outside of event_mutex 
context")