driver_find_device() calls get_device() to increment the reference count once a matching device is found. device_release_driver() releases the driver, but it does not decrease the reference count that was incremented by driver_find_device(). At the end of the loop, there is no put_device() to balance the reference count. To avoid reference count leakage, add put_device() to decrease the reference count.

Found by code review.

Cc: stable@vger.kernel.org Fixes: bfc653aa89cb ("perf: arm_cspmu: Separate Arm and vendor module") Signed-off-by: Ma Ke make24@iscas.ac.cn --- drivers/perf/arm_cspmu/arm_cspmu.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/perf/arm_cspmu/arm_cspmu.c b/drivers/perf/arm_cspmu/arm_cspmu.c index efa9b229e701..e0d4293f06f9 100644 --- a/drivers/perf/arm_cspmu/arm_cspmu.c +++ b/drivers/perf/arm_cspmu/arm_cspmu.c @@ -1365,8 +1365,10 @@ void arm_cspmu_impl_unregister(const struct arm_cspmu_impl_match *impl_match)

/* Unbind the driver from all matching backend devices. */ while ((dev = driver_find_device(&arm_cspmu_driver.driver, NULL, - match, arm_cspmu_match_device))) + match, arm_cspmu_match_device))) { device_release_driver(dev); + put_device(dev); + }

mutex_lock(&arm_cspmu_lock);