This is a note to let you know that I've just added the patch titled
coresight: etm4x: Fix unbalanced pm_runtime_enable()
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
coresight-etm4x-fix-unbalanced-pm_runtime_enable.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 5f219d57184fe676e237174f3738e17e6de28b54
Author: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Date: Thu Mar 14 11:28:33 2024 +0530
coresight: etm4x: Fix unbalanced pm_runtime_enable()
[ 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@xxxxxxxxxx>
Cc: Hanjun Guo <guohanjun@xxxxxxxxxx>
Cc: Sudeep Holla <sudeep.holla@xxxxxxx>
Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx>
Cc: Len Brown <lenb@xxxxxxxxxx>
Cc: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Cc: Mike Leach <mike.leach@xxxxxxxxxx>
Cc: James Clark <james.clark@xxxxxxx>
Cc: Leo Yan <leo.yan@xxxxxxxxxx>
Cc: linux-acpi@xxxxxxxxxxxxxxx
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: coresight@xxxxxxxxxxxxxxxx
Fixes: 5214b563588e ("coresight: etm4x: Add support for sysreg only devices")
Reviewed-by: James Clark <james.clark@xxxxxxx>
Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Link: https://lore.kernel.org/r/20240314055843.2625883-2-anshuman.khandual@xxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
index 18c4544f60454..003245a791a23 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
@@ -2175,6 +2175,9 @@ 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;
}
