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Date: Wed, 19 Oct 2016 09:25:04 +0200
From: Daniel Vetter <daniel@ffwll.ch>
To: Chris Wilson <chris@chris-wilson.co.uk>, Arnd Bergmann <arnd@arndb.de>,
        Daniel Vetter <daniel.vetter@intel.com>,
        Jani Nikula <jani.nikula@linux.intel.com>,
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        Ander Conselvan de Oliveira 
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        linux-kernel@vger.kernel.org
Subject: Re: [Intel-gfx] [PATCH] i915: don't call drm_atomic_state_put on
 invalid pointer
Message-ID: <20161019072504.GD20761@phenom.ffwll.local>
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        Imre Deak <imre.deak@intel.com>,
        Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>,
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On Tue, Oct 18, 2016 at 04:56:02PM +0100, Chris Wilson wrote:
> On Tue, Oct 18, 2016 at 05:16:23PM +0200, Arnd Bergmann wrote:
> > The introduction of reference counting on the state structures caused
> > sanitize_watermarks() in i915 to break in the error handling case,
> > as pointed out by gcc -Wmaybe-uninitialized
> > 
> > drivers/gpu/drm/i915/intel_display.c: In function ‘intel_modeset_init’:
> > include/drm/drm_atomic.h:224:2: error: ‘state’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
> > 
> > This changes the function back to only drop the reference count
> > when it was successfully allocated first.
> > 
> > Fixes: 0853695c3ba4 ("drm: Add reference counting to drm_atomic_state")
> > Cc: Chris Wilson <chris@chris-wilson.co.uk>
> > Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> > Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> 
> Yup, missed that it jumps to fail before allocating state.
> 
> Function still looks a bit odd, but nvm
> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>

Applied to drm-misc, thanks for the patch&review.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch