From: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Date: Tue, 26 Sep 2023 08:32:29 +0000 (+0200)
Subject: soc: qcom: llcc: Handle a second device without data corruption
X-Git-Tag: v5.15.139~123
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=995ee1e84e8db7fa5dcdde7dfe0bd7bb6f9bbb8c;p=thirdparty%2Fkernel%2Fstable.git

soc: qcom: llcc: Handle a second device without data corruption

[ Upstream commit f1a1bc8775b26345aba2be278118999e7f661d3d ]

Usually there is only one llcc device. But if there were a second, even
a failed probe call would modify the global drv_data pointer. So check
if drv_data is valid before overwriting it.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Fixes: a3134fb09e0b ("drivers: soc: Add LLCC driver")
Link: https://lore.kernel.org/r/20230926083229.2073890-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/drivers/soc/qcom/llcc-qcom.c b/drivers/soc/qcom/llcc-qcom.c
index 47d41804fdf67..fabc5ce828af3 100644
--- a/drivers/soc/qcom/llcc-qcom.c
+++ b/drivers/soc/qcom/llcc-qcom.c
@@ -537,6 +537,9 @@ static int qcom_llcc_probe(struct platform_device *pdev)
 	u32 sz;
 	u32 version;
 
+	if (!IS_ERR(drv_data))
+		return -EBUSY;
+
 	drv_data = devm_kzalloc(dev, sizeof(*drv_data), GFP_KERNEL);
 	if (!drv_data) {
 		ret = -ENOMEM;