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From:   Robert Foss <rfoss@kernel.org>
To:     AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>,
        Xin Ji <xji@analogixsemi.com>,
        Chen-Yu Tsai <wenst@chromium.org>,
        Andrzej Hajda <andrzej.hajda@intel.com>,
        Laurent Pinchart <Laurent.pinchart@ideasonboard.com>,
        Neil Armstrong <neil.armstrong@linaro.org>,
        Jernej Skrabec <jernej.skrabec@gmail.com>,
        =?UTF-8?q?N=C3=ADcolas=20F=20=2E=20R=20=2E=20A=20=2E=20Prado?= 
        <nfraprado@collabora.com>, Jonas Karlman <jonas@kwiboo.se>
Cc:     Robert Foss <rfoss@kernel.org>, dri-devel@lists.freedesktop.org,
        Daniel Vetter <daniel@ffwll.ch>, linux-kernel@vger.kernel.org,
        David Airlie <airlied@gmail.com>
Subject: Re: [PATCH v2] drm/bridge: anx7625: Drop device lock before drm_helper_hpd_irq_event()
Date:   Mon, 24 Jul 2023 10:16:56 +0200
Message-ID: <169018660964.606978.4469347765082724733.b4-ty@kernel.org>
In-Reply-To: <20230710085922.1871465-1-wenst@chromium.org>
References: <20230710085922.1871465-1-wenst@chromium.org>
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On Mon, 10 Jul 2023 16:59:21 +0800, Chen-Yu Tsai wrote:
> The device lock is used to serialize the low level power sequencing
> operations. Since drm_helper_hpd_irq_event() could end up calling
> .atomic_enable, which also calls power sequencing functions through
> runtime PM, this results in a real deadlock. This was observed on an
> MT8192-based Chromebook's external display (with appropriate patches [1]
> and DT changes applied).
> 
> [...]

Applied, thanks!

[1/1] drm/bridge: anx7625: Drop device lock before drm_helper_hpd_irq_event()
      https://cgit.freedesktop.org/drm/drm-misc/commit/?id=f2cca20f1fa3


Rob