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Date:   Fri, 08 Apr 2022 13:26:50 +0000
To:     Grigory Vasilyev <h0tc0d3@gmail.com>
From:   Simon Ser <contact@emersion.fr>
Cc:     Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>,
        Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>,
        Melissa Wen <mwen@igalia.com>,
        Alex Deucher <alexander.deucher@amd.com>,
        =?utf-8?Q?Christian_K=C3=B6nig?= <christian.koenig@amd.com>,
        "Pan, Xinhui" <Xinhui.Pan@amd.com>,
        David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>,
        =?utf-8?Q?Michel_D=C3=A4nzer?= <mdaenzer@redhat.com>,
        Evan Quan <evan.quan@amd.com>,
        Sean Paul <seanpaul@chromium.org>,
        Qingqing Zhuo <qingqing.zhuo@amd.com>,
        amd-gfx mailing list <amd-gfx@lists.freedesktop.org>,
        ML dri-devel <dri-devel@lists.freedesktop.org>,
        LKML <linux-kernel@vger.kernel.org>
Reply-To: Simon Ser <contact@emersion.fr>
Subject: Re: [PATCH] drm/amdgpu: Fix NULL pointer dereference
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On Friday, April 8th, 2022 at 15:21, Grigory Vasilyev <h0tc0d3@gmail.com> w=
rote:

> Simon Ser and Bas Nieuwenhuizen, do you understand that you are
> proposing to make the code less safe in the future? In the future,
> someone might rewrite the code and we'll get an error.

I don't think we should blindly add NULL checks for all functions which
take a pointer as argument. This makes it way more complicated to find
a bug when the function is mis-used. Crashing is better because it
indicates a programmer error. In the future, any new call with a NULL
pointer will produce a clear error.

Using pointers for output values is a common pattern in C, it allows a
function to return multiple values.