Commit feec214a authored Jan 18, 2020 by Amol Grover Committed by Olof Johansson Jan 19, 2020

drivers: soc: ti: knav_qmss_queue: Pass lockdep expression to RCU lists

inst->handles is traversed using list_for_each_entry_rcu
outside an RCU read-side critical section but under the protection
of knav_dev_lock.

Hence, add corresponding lockdep expression to silence false-positive
lockdep warnings, and harden RCU lists.

Add macro for the corresponding lockdep expression.

Link: https://lore.kernel.org/r/20200118042433.4968-1-frextrite@gmail.com


Signed-off-by: Amol Grover <frextrite@gmail.com>
Acked-by: Santosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: Olof Johansson <olof@lixom.net>

parent 2ced5a34

drivers/soc/ti/knav_qmss_queue.c

+5 −2

Original line number	Diff line number	Diff line
		@@ -25,6 +25,8 @@

		static struct knav_device *kdev;
		static DEFINE_MUTEX(knav_dev_lock);
		#define knav_dev_lock_held() \
		lockdep_is_held(&knav_dev_lock)

		/* Queue manager register indices in DTS */
		#define KNAV_QUEUE_PEEK_REG_INDEX 0
		@@ -53,7 +55,8 @@ static DEFINE_MUTEX(knav_dev_lock);
		(kdev->instances + (idx << kdev->inst_shift))

		#define for_each_handle_rcu(qh, inst) \
		list_for_each_entry_rcu(qh, &inst->handles, list)
		list_for_each_entry_rcu(qh, &inst->handles, list, \
		knav_dev_lock_held())

		#define for_each_instance(idx, inst, kdev) \
		for (idx = 0, inst = kdev->instances; \

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