Re: [PATCH v2 00/10] drm/msm: probe deferral fixes

From: Rob Clark
Date: Mon Oct 24 2022 - 12:56:29 EST


On Mon, Oct 24, 2022 at 4:34 AM Johan Hovold <johan@xxxxxxxxxx> wrote:
>
> On Fri, Oct 21, 2022 at 09:05:52AM -0700, Abhinav Kumar wrote:
> > Hi Johan
> >
> > On 10/20/2022 11:27 PM, Johan Hovold wrote:
> > > On Tue, Sep 20, 2022 at 11:06:30AM +0200, Johan Hovold wrote:
> > >> On Tue, Sep 13, 2022 at 10:53:10AM +0200, Johan Hovold wrote:
> > >>> The MSM DRM driver is currently broken in multiple ways with respect to
> > >>> probe deferral. Not only does the driver currently fail to probe again
> > >>> after a late deferral, but due to a related use-after-free bug this also
> > >>> triggers NULL-pointer dereferences.
> > >>>
> > >>> These bugs are not new but have become critical with the release of
> > >>> 5.19 where probe is deferred in case the aux-bus EP panel driver has not
> > >>> yet been loaded.
> > >>>
> > >>> The underlying problem is lifetime issues due to careless use of
> > >>> device-managed resources.
> > >>
> > >> Any chance of getting this merged for 6.1?
> > >
> > > Is anyone picking these up as fixes for 6.1-rc as we discussed?
> > >
> > > Johan
> >
> > All of these except the last two ( as discussed ) have landed in the
> > -fixes tree
> >
> > https://gitlab.freedesktop.org/drm/msm/-/commit/6808abdb33bf90330e70a687d29f038507e06ebb
>
> Ah, perfect, thanks.
>
> When do you expect to send these on so that they end up in linux-next
> and eventually Linus's tree?

I'll send a -fixes PR this week

> Note that it looks like something happened with the commit messages when
> you applied these. Specifically, the Fixes tags appears to now have a
> line break in them and there's also some random whitespace before your
> SoB:
>
> Fixes: c3bf8e21
>
> ("drm/msm/dp: Add eDP support via aux_bus")

naw, that is just some problem with gitlab's html generation, the
actual patch is fine ;-)

BR,
-R

> Cc: stable@xxxxxxxxxxxxxxx # 5.19
> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
> Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx>
> Tested-by: Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx>
> Reviewed-by: Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx>
> Patchwork: https://patchwork.freedesktop.org/patch/502667/
> Link: https://lore.kernel.org/r/20220913085320.8577-8-johan+linaro@xxxxxxxxxx
>
>
> Signed-off-by: Abhinav Kumar's avatarAbhinav Kumar <quic_abhinavk@xxxxxxxxxxx>
>
> It's possible just the gitlab UI that's messed up, but perhaps you can
> double check before they hit linux-next, which should complain about
> this otherwise.
>
> Johan