[PATCH] drm/cirrus: Fix NULL pointer dereference when registering the fbdev

[Boris Brezillon]

On Mon, 08 Aug 2016 22:36:13 -0500
ebiederm at xmission.com (Eric W. Biederman) wrote:

> Boris Brezillon <boris.brezillon at free-electrons.com> writes:
> 
> > cirrus_modeset_init() is initializing/registering the emulated fbdev
> > and, since commit c61b93fe51b1 ("drm/atomic: Fix remaining places where
> > !funcs->best_encoder is valid"), DRM internals can access/test some of
> > the fields in mode_config->funcs as part of the fbdev registration
> > process.
> > Make sure dev->mode_config.funcs is properly set to avoid dereferencing
> > a NULL pointer.  
> 
> That fixes the issues I am seeing.
> 
> Tested-by: "Eric W. Biederman" <ebiederm at xmission.com>
> 
> > Signed-off-by: Boris Brezillon <boris.brezillon at free-electrons.com>
> > Fixes: c61b93fe51b1 ("drm/atomic: Fix remaining places where !funcs->best_encoder is valid")
> > ---
> > Hi Dave,
> >
> > As discussed on IRC, I'm sending this patch in a proper format. That's
> > probably better to wait for Eric's feeback before applying it though.  
> 
> It is weird I didn't see either of your email messages directly only
> through lkml.  Weird.

Probably because of that

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