[PATCH] bus: mhi: core: Remove double locking from mhi_driver_remove()

From: Bhaumik Bhatt
Date: Thu Oct 15 2020 - 14:48:02 EST


There is double acquisition of the pm_lock from mhi_driver_remove()
function. Remove the read_lock_bh/read_unlock_bh calls for pm_lock
taken during a call to mhi_device_put() as the lock is acquired
within the function already. This will help avoid a potential
kernel panic.

Fixes: 189ff97cca53 ("bus: mhi: core: Add support for data transfer")
Reported-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Bhaumik Bhatt <bbhatt@xxxxxxxxxxxxxx>
---
drivers/bus/mhi/core/init.c | 2 --
1 file changed, 2 deletions(-)

diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
index 0ffdebd..0a09f82 100644
--- a/drivers/bus/mhi/core/init.c
+++ b/drivers/bus/mhi/core/init.c
@@ -1276,10 +1276,8 @@ static int mhi_driver_remove(struct device *dev)
mutex_unlock(&mhi_chan->mutex);
}

- read_lock_bh(&mhi_cntrl->pm_lock);
while (mhi_dev->dev_wake)
mhi_device_put(mhi_dev);
- read_unlock_bh(&mhi_cntrl->pm_lock);

return 0;
}
--
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