6.1-stable review patch. If anyone has any objections, please let me know.
------------------
From: Anshuman Khandual anshuman.khandual@arm.com
[ Upstream commit caa41c47dab7e1054f587e592ab21296e3a6781c ]
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().
Cc: Lorenzo Pieralisi lpieralisi@kernel.org Cc: Hanjun Guo guohanjun@huawei.com Cc: Sudeep Holla sudeep.holla@arm.com Cc: "Rafael J. Wysocki" rafael@kernel.org Cc: Len Brown lenb@kernel.org Cc: Suzuki K Poulose suzuki.poulose@arm.com Cc: Mike Leach mike.leach@linaro.org Cc: James Clark james.clark@arm.com Cc: Leo Yan leo.yan@linaro.org Cc: linux-acpi@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: coresight@lists.linaro.org Fixes: 5214b563588e ("coresight: etm4x: Add support for sysreg only devices") Reviewed-by: James Clark james.clark@arm.com Signed-off-by: Anshuman Khandual anshuman.khandual@arm.com Signed-off-by: Suzuki K Poulose suzuki.poulose@arm.com Link: https://lore.kernel.org/r/20240314055843.2625883-2-anshuman.khandual@arm.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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 fda48a0afc1a5..63fe506a60314 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c @@ -2053,6 +2053,9 @@ static int etm4_probe_platform_dev(struct platform_device *pdev) ret = etm4_probe(&pdev->dev, NULL, 0);
pm_runtime_put(&pdev->dev); + if (ret) + pm_runtime_disable(&pdev->dev); + return ret; }