[PATCH v2 2/3] thermal: qcom: lmh: Check for SCM availability at probe

From: Konrad Dybcio <konrad.dybcio@linaro.org>
To: Bjorn Andersson <andersson@kernel.org>,
	 "Rafael J. Wysocki" <rafael@kernel.org>,
	 Daniel Lezcano <daniel.lezcano@linaro.org>,
	Zhang Rui <rui.zhang@intel.com>,
	 Lukasz Luba <lukasz.luba@arm.com>, Rob Herring <robh@kernel.org>,
	 Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	 Conor Dooley <conor+dt@kernel.org>,
	 Thara Gopinath <thara.gopinath@gmail.com>,
	Amit Kucheria <amitk@kernel.org>
Cc: Marijn Suijten <marijn.suijten@somainline.org>,
	 linux-arm-msm@vger.kernel.org, linux-pm@vger.kernel.org,
	 devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	 Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
	 Konrad Dybcio <konrad.dybcio@linaro.org>,
	stable@vger.kernel.org
Subject: [PATCH v2 2/3] thermal: qcom: lmh: Check for SCM availability at probe
Date: Sat, 09 Mar 2024 14:15:03 +0100	[thread overview]
Message-ID: <20240308-topic-rb1_lmh-v2-2-bac3914b0fe3@linaro.org> (raw)
In-Reply-To: <20240308-topic-rb1_lmh-v2-0-bac3914b0fe3@linaro.org>

Up until now, the necessary scm availability check has not been
performed, leading to possible null pointer dereferences (which did
happen for me on RB1).

Fix that.

Fixes: 53bca371cdf7 ("thermal/drivers/qcom: Add support for LMh driver")
Cc: <stable@vger.kernel.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
---
 drivers/thermal/qcom/lmh.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/thermal/qcom/lmh.c b/drivers/thermal/qcom/lmh.c
index f6edb12ec004..5225b3621a56 100644
--- a/drivers/thermal/qcom/lmh.c
+++ b/drivers/thermal/qcom/lmh.c
@@ -95,6 +95,9 @@ static int lmh_probe(struct platform_device *pdev)
 	unsigned int enable_alg;
 	u32 node_id;
 
+	if (!qcom_scm_is_available())
+		return -EPROBE_DEFER;
+
 	lmh_data = devm_kzalloc(dev, sizeof(*lmh_data), GFP_KERNEL);
 	if (!lmh_data)
 		return -ENOMEM;

-- 
2.44.0

