linux-kernel - [PATCH v5 2/8] i2c: tegra: Properly disable runtime PM on driver's probe error

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20200114013442.28448-3-digetx@gmail.com>
Date:   Tue, 14 Jan 2020 04:34:36 +0300
From:   Dmitry Osipenko <digetx@...il.com>
To:     Thierry Reding <thierry.reding@...il.com>,
        Jonathan Hunter <jonathanh@...dia.com>,
        Laxman Dewangan <ldewangan@...dia.com>,
        Mikko Perttunen <cyndis@...si.fi>,
        Wolfram Sang <wsa@...-dreams.de>
Cc:     linux-i2c@...r.kernel.org, linux-tegra@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH v5 2/8] i2c: tegra: Properly disable runtime PM on driver's probe error

One of the recent Tegra I2C commits made a change that resumes runtime PM
during driver's probe, but it missed to put the RPM in a case of error.
Note that it's not correct to use pm_runtime_status_suspended because it
breaks RPM refcounting.

Fixes: 8ebf15e9c869 ("i2c: tegra: Move suspend handling to NOIRQ phase")
Cc: <stable@...r.kernel.org> # v5.4+
Tested-by: Thierry Reding <treding@...dia.com>
Signed-off-by: Dmitry Osipenko <digetx@...il.com>
---
 drivers/i2c/busses/i2c-tegra.c | 29 +++++++++++++++++++----------
 1 file changed, 19 insertions(+), 10 deletions(-)

diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 79d19f6ce94e..61339c665ebd 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -1608,14 +1608,18 @@ static int tegra_i2c_probe(struct platform_device *pdev)
 	}
 
 	pm_runtime_enable(&pdev->dev);
-	if (!pm_runtime_enabled(&pdev->dev))
+	if (!pm_runtime_enabled(&pdev->dev)) {
 		ret = tegra_i2c_runtime_resume(&pdev->dev);
-	else
+		if (ret < 0) {
+			dev_err(&pdev->dev, "runtime resume failed\n");
+			goto unprepare_div_clk;
+		}
+	} else {
 		ret = pm_runtime_get_sync(i2c_dev->dev);
-
-	if (ret < 0) {
-		dev_err(&pdev->dev, "runtime resume failed\n");
-		goto unprepare_div_clk;
+		if (ret < 0) {
+			dev_err(&pdev->dev, "runtime resume failed\n");
+			goto disable_rpm;
+		}
 	}
 
 	if (i2c_dev->is_multimaster_mode) {
@@ -1623,7 +1627,7 @@ static int tegra_i2c_probe(struct platform_device *pdev)
 		if (ret < 0) {
 			dev_err(i2c_dev->dev, "div_clk enable failed %d\n",
 				ret);
-			goto disable_rpm;
+			goto put_rpm;
 		}
 	}
 
@@ -1671,11 +1675,16 @@ static int tegra_i2c_probe(struct platform_device *pdev)
 	if (i2c_dev->is_multimaster_mode)
 		clk_disable(i2c_dev->div_clk);
 
-disable_rpm:
-	pm_runtime_disable(&pdev->dev);
-	if (!pm_runtime_status_suspended(&pdev->dev))
+put_rpm:
+	if (pm_runtime_enabled(&pdev->dev))
+		pm_runtime_put_sync(&pdev->dev);
+	else
 		tegra_i2c_runtime_suspend(&pdev->dev);
 
+disable_rpm:
+	if (pm_runtime_enabled(&pdev->dev))
+		pm_runtime_disable(&pdev->dev);
+
 unprepare_div_clk:
 	clk_unprepare(i2c_dev->div_clk);
 
-- 
2.24.0