From:   Johan Hovold <johan+linaro@kernel.org>
To:     Rob Clark <robdclark@gmail.com>,
        Abhinav Kumar <quic_abhinavk@quicinc.com>,
        Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Cc:     Sean Paul <sean@poorly.run>, David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>, linux-arm-msm@vger.kernel.org,
        dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org,
        linux-kernel@vger.kernel.org,
        Johan Hovold <johan+linaro@kernel.org>, stable@vger.kernel.org,
        Thomas Zimmermann <tzimmermann@suse.de>
Subject: [PATCH 04/10] drm/msm: fix NULL-deref on irq uninstall
Date:   Mon,  6 Mar 2023 11:07:16 +0100
Message-Id: <20230306100722.28485-5-johan+linaro@kernel.org>
In-Reply-To: <20230306100722.28485-1-johan+linaro@kernel.org>
References: <20230306100722.28485-1-johan+linaro@kernel.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

In case of early initialisation errors and on platforms that do not use
the DPU controller, the deinitilisation code can be called with the kms
pointer set to NULL.

Fixes: f026e431cf86 ("drm/msm: Convert to Linux IRQ interfaces")
Cc: stable@vger.kernel.org	# 5.14
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
---
 drivers/gpu/drm/msm/msm_drv.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
index 17a59d73fe01..2f2bcdb671d2 100644
--- a/drivers/gpu/drm/msm/msm_drv.c
+++ b/drivers/gpu/drm/msm/msm_drv.c
@@ -251,9 +251,11 @@ static int msm_drm_uninit(struct device *dev)
 		drm_bridge_remove(priv->bridges[i]);
 	priv->num_bridges = 0;
 
-	pm_runtime_get_sync(dev);
-	msm_irq_uninstall(ddev);
-	pm_runtime_put_sync(dev);
+	if (kms) {
+		pm_runtime_get_sync(dev);
+		msm_irq_uninstall(ddev);
+		pm_runtime_put_sync(dev);
+	}
 
 	if (kms && kms->funcs)
 		kms->funcs->destroy(kms);
-- 
2.39.2