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Subject: Re: [PATCH] drm/i915/selftests: Fix uninitialized variable
To: Chris Wilson <chris@chris-wilson.co.uk>,
        Jani Nikula <jani.nikula@linux.intel.com>,
        Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
        Rodrigo Vivi <rodrigo.vivi@intel.com>, David Airlie <airlied@linux.ie>
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References: <20180424131545.GA4053@embeddedor.com>
 <152457614368.12387.9348969127399551440@mail.alporthouse.com>
From: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Message-ID: <09f02909-90cb-60f0-e362-7d5314dd8964@embeddedor.com>
Date: Tue, 24 Apr 2018 08:30:58 -0500
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On 04/24/2018 08:22 AM, Chris Wilson wrote:
> Quoting Gustavo A. R. Silva (2018-04-24 14:15:45)
>> There is a potential execution path in which variable err is
>> returned without being properly initialized previously.
>>
>> Fix this by initializing variable err to 0.
> 
> err is only returned along an error path, returning 0 would not be
> useful. Which path? All the error paths look correct to me.
> -Chris
> 

If the following two conditions take the false branch then the function 
returns err with a random stack value:

if (intel_has_reset_engine(i915)) {
		...
}

if (intel_has_gpu_reset(i915)) {
		...
}

Thanks
--
Gustavo