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Subject: Re: [PATCH] drm/radeon: Handle workqueue allocation failure
To:     Will Deacon <will@kernel.org>
Cc:     amd-gfx@lists.freedesktop.org, David Airlie <airlied@linux.ie>,
        linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org,
        Nicolas Waisman <nico@semmle.com>,
        Alex Deucher <alexander.deucher@amd.com>,
        =?UTF-8?Q?Christian_K=c3=b6nig?= <christian.koenig@amd.com>
References: <20191025110450.10474-1-will@kernel.org>
 <5d6a88a2-2719-a859-04df-10b0d893ff39@daenzer.net>
 <20191025161804.GA12335@willie-the-truck>
From:   =?UTF-8?Q?Michel_D=c3=a4nzer?= <michel@daenzer.net>
Message-ID: <e2f87ecc-0a8e-253d-107c-5cf6486c4b6a@daenzer.net>
Date:   Fri, 25 Oct 2019 18:20:01 +0200
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On 2019-10-25 6:18 p.m., Will Deacon wrote:
> On Fri, Oct 25, 2019 at 06:06:26PM +0200, Michel Dänzer wrote:
>> On 2019-10-25 1:04 p.m., Will Deacon wrote:
>>> In the highly unlikely event that we fail to allocate the "radeon-crtc"
>>> workqueue, we should bail cleanly rather than blindly march on with a
>>> NULL pointer installed for the 'flip_queue' field of the 'radeon_crtc'
>>> structure.
>>>
>>> This was reported previously by Nicolas, but I don't think his fix was
>>> correct:
>>
>> Neither is this one I'm afraid. See my feedback on
>> https://patchwork.freedesktop.org/patch/331534/ .
> 
> Thanks. Although I agree with you wrt the original patch, I don't think
> the workqueue allocation failure is distinguishable from the CRTC allocation
> failure with my patch. Are you saying that the error path there is broken
> too?

The driver won't actually work if radeon_crtc_init bails silently, it'll
just fall over at some later point.


-- 
Earthling Michel Dänzer               |               https://redhat.com
Libre software enthusiast             |             Mesa and X developer