Re: [PATCH] i915: don't call drm_atomic_state_put on invalid pointer

[Chris Wilson]

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 âintel_modeset_initâ:
> include/drm/drm_atomic.h:224:2: error: âstateâ 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@xxxxxxxxxxxxxxxxxx>
> Cc: Daniel Vetter <daniel.vetter@xxxxxxxx>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>

Yup, missed that it jumps to fail before allocating state.

Function still looks a bit odd, but nvm
Reviewed-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre