This is a note to let you know that I've just added the patch titled
regulator: core: Consistently set mutex_owner when using ww_mutex_lock_slow()
to the 5.4-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-consistently-set-mutex_owner-when-usi.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 064dc52130a2222faae19e7b286a5d40519cab7f
Author: Douglas Anderson <dianders@xxxxxxxxxxxx>
Date: Wed Mar 29 14:33:53 2023 -0700
regulator: core: Consistently set mutex_owner when using ww_mutex_lock_slow()
[ Upstream commit b83a1772be854f87602de14726737d3e5b06e1f4 ]
When a codepath locks a rdev using ww_mutex_lock_slow() directly then
that codepath is responsible for incrementing the "ref_cnt" and also
setting the "mutex_owner" to "current".
The regulator core consistently got that right for "ref_cnt" but
didn't always get it right for "mutex_owner". Let's fix this.
It's unlikely that this truly matters because the "mutex_owner" is
only needed if we're going to do subsequent locking of the same
rdev. However, even though it's not truly needed it seems less
surprising if we consistently set "mutex_owner" properly.
Fixes: f8702f9e4aa7 ("regulator: core: Use ww_mutex for regulators locking")
Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230329143317.RFC.v2.1.I4e9d433ea26360c06dd1381d091c82bb1a4ce843@changeid
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 0179716f74d74..1cdf924c0111b 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -344,6 +344,7 @@ static void regulator_lock_dependent(struct regulator_dev *rdev,
ww_mutex_lock_slow(&new_contended_rdev->mutex, ww_ctx);
old_contended_rdev = new_contended_rdev;
old_contended_rdev->ref_cnt++;
+ old_contended_rdev->mutex_owner = current;
}
err = regulator_lock_recursive(rdev,
@@ -5659,6 +5660,7 @@ static void regulator_summary_lock(struct ww_acquire_ctx *ww_ctx)
ww_mutex_lock_slow(&new_contended_rdev->mutex, ww_ctx);
old_contended_rdev = new_contended_rdev;
old_contended_rdev->ref_cnt++;
+ old_contended_rdev->mutex_owner = current;
}
err = regulator_summary_lock_all(ww_ctx,
