This is a note to let you know that I've just added the patch titled
regulator: core: Fix enable_count imbalance with EXCLUSIVE_GET
to the 5.15-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:
regulator-core-fix-enable_count-imbalance-with-exclu.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 79363b3be82e2a909f4a24d45771447868065ff0
Author: Zev Weiss <zev@xxxxxxxxxxxxxxxxx>
Date: Wed May 4 21:31:52 2022 -0700
regulator: core: Fix enable_count imbalance with EXCLUSIVE_GET
[ Upstream commit c3e3ca05dae37f8f74bb80358efd540911cbc2c8 ]
Since the introduction of regulator->enable_count, a driver that did
an exclusive get on an already-enabled regulator would end up with
enable_count initialized to 0 but rdev->use_count initialized to 1.
With that starting point the regulator is effectively stuck enabled,
because if the driver attempted to disable it it would fail the
enable_count underflow check in _regulator_handle_consumer_disable().
The EXCLUSIVE_GET path in _regulator_get() now initializes
enable_count along with rdev->use_count so that the regulator can be
disabled without underflowing the former.
Signed-off-by: Zev Weiss <zev@xxxxxxxxxxxxxxxxx>
Fixes: 5451781dadf85 ("regulator: core: Only count load for enabled consumers")
Link: https://lore.kernel.org/r/20220505043152.12933-1-zev@xxxxxxxxxxxxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 46e76b5b21ef..f4f28e5888b1 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -2132,10 +2132,13 @@ struct regulator *_regulator_get(struct device *dev, const char *id,
rdev->exclusive = 1;
ret = _regulator_is_enabled(rdev);
- if (ret > 0)
+ if (ret > 0) {
rdev->use_count = 1;
- else
+ regulator->enable_count = 1;
+ } else {
rdev->use_count = 0;
+ regulator->enable_count = 0;
+ }
}
link = device_link_add(dev, &rdev->dev, DL_FLAG_STATELESS);
