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Date:   Fri, 18 Mar 2022 11:21:41 +0100
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Subject: Re: [PATCH 2/2 RESEND] drm/bridge: Add extra checks in pre_enable and
 post_enable
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To:     =?UTF-8?Q?Ricardo_Ca=c3=b1uelo?= <ricardo.canuelo@collabora.com>,
        dri-devel@lists.freedesktop.org
Cc:     linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org,
        kernel@collabora.com, andrzej.hajda@intel.com,
        narmstrong@baylibre.com, maarten.lankhorst@linux.intel.com,
        mripard@kernel.org
References: <20220311093406.4068019-1-ricardo.canuelo@collabora.com>
 <20220311093406.4068019-3-ricardo.canuelo@collabora.com>
From:   AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>
In-Reply-To: <20220311093406.4068019-3-ricardo.canuelo@collabora.com>
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Il 11/03/22 10:34, Ricardo Cañuelo ha scritto:
> Depending on the bridge code, certain userspace events during a driver
> teardown (such as a DRM ioctl call) might cause a race condition where
> the drm_bridge_chain_pre_enable() and drm_bridge_chain_post_enable()
> functions could be called for a bridge that has just been detached and
> removed from the bridge chain of an encoder.
> 
> This change makes these functions a bit more robust by bailing out if
> the bridge has already been detached.
> 
> Tested on an Acer Chromebook R13 (Elm, MT8173) with Debian Sid.
> 
> Signed-off-by: Ricardo Cañuelo <ricardo.canuelo@collabora.com>

On various chromebooks with different MediaTek SoC models, and on
Qualcomm SC7180 Trogdor,

Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>