Subject: Re: [PATCH 1/3] drm/vc4: Fix double destroy of the BO cache on
 teardown.
To: Eric Anholt <eric@anholt.net>, dri-devel@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org
References: <20170802203242.12815-1-eric@anholt.net>
From: =?UTF-8?Q?Noralf_Tr=c3=b8nnes?= <noralf@tronnes.org>
Message-ID: <bfa71e20-6822-bb01-cef0-5966180f4b9f@tronnes.org>
Date: Wed, 2 Aug 2017 22:53:06 +0200
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Den 02.08.2017 22.32, skrev Eric Anholt:
> It's also destroyed from the top level vc4_drv.c initialization, which
> is where the cache was actually initialized from.
>
> This used to just involve duplicate del_timer() and cancel_work_sync()
> being called, but it started causing kmalloc issues once we
> double-freed the new BO label array.
>
> Fixes: 1908a876f909 ("drm/vc4: Add an ioctl for labeling GEM BOs for summary stats")
> Signed-off-by: Eric Anholt <eric@anholt.net>
> ---
>   drivers/gpu/drm/vc4/vc4_gem.c | 2 --
>   1 file changed, 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/vc4/vc4_gem.c b/drivers/gpu/drm/vc4/vc4_gem.c
> index 209fccd0d3b4..892a031a3ced 100644
> --- a/drivers/gpu/drm/vc4/vc4_gem.c
> +++ b/drivers/gpu/drm/vc4/vc4_gem.c
> @@ -1117,6 +1117,4 @@ vc4_gem_destroy(struct drm_device *dev)
>   
>   	if (vc4->hang_state)
>   		vc4_free_hang_state(dev, vc4->hang_state);
> -
> -	vc4_bo_cache_destroy(dev);
>   }

I don't have a display connected, but there's no crashing anymore.

Tested-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Noralf Trønnes <noralf@tronnes.org>