Re: [PATCH V4 01/11] coresight: etm4x: Fix unbalanced pm_runtime_enable()
From: Suzuki K Poulose <suzuki.poulose@arm.com>
Date: 2024-02-15 11:04:08
Also in:
linux-acpi, lkml
On 23/01/2024 05:45, Anshuman Khandual wrote:
There is an unbalanced pm_runtime_enable() in etm4_probe_platform_dev() when etm4_probe() fails. This problem can be observed via the coresight etm4 module's (load -> unload -> load) sequence when etm4_probe() fails in etm4_probe_platform_dev(). [ 63.379943] coresight-etm4x 7040000.etm: Unbalanced pm_runtime_enable! [ 63.393630] coresight-etm4x 7140000.etm: Unbalanced pm_runtime_enable! [ 63.407455] coresight-etm4x 7240000.etm: Unbalanced pm_runtime_enable! [ 63.420983] coresight-etm4x 7340000.etm: Unbalanced pm_runtime_enable! [ 63.420999] coresight-etm4x 7440000.etm: Unbalanced pm_runtime_enable! [ 63.441209] coresight-etm4x 7540000.etm: Unbalanced pm_runtime_enable! [ 63.454689] coresight-etm4x 7640000.etm: Unbalanced pm_runtime_enable! [ 63.474982] coresight-etm4x 7740000.etm: Unbalanced pm_runtime_enable! This fixes the above problem - with an explicit pm_runtime_disable() call when etm4_probe() fails during etm4_probe_platform_dev().
Fixes: 5214b563588e ("coresight: etm4x: Add support for sysreg only devices"
quoted hunk ↗ jump to hunk
Cc: Lorenzo Pieralisi <lpieralisi@kernel.org> Cc: Hanjun Guo <guohanjun@huawei.com> Cc: Sudeep Holla <redacted> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Len Brown <lenb@kernel.org> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Mike Leach <redacted> Cc: James Clark <redacted> Cc: Leo Yan <redacted> Cc: linux-acpi@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: coresight@lists.linaro.org Signed-off-by: Anshuman Khandual <redacted> --- Changes in V4: - New patch in the series drivers/hwtracing/coresight/coresight-etm4x-core.c | 3 +++ 1 file changed, 3 insertions(+)diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c index ce1995a2827f..7c693b45ac05 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c@@ -2217,6 +2217,9 @@ static int etm4_probe_platform_dev(struct platform_device *pdev) ret = etm4_probe(&pdev->dev); pm_runtime_put(&pdev->dev); + if (ret) + pm_runtime_disable(&pdev->dev); + return ret; }
Looks good to me. I have glanced through the other platform device driver code in coresight subsystem and they all seem to be safe, except for Ultrasoc-smb, which doesn't do any power managment. It may be, because it is only supported on an ACPI system. Suzuki _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel