Re: [PATCH v5] workqueue: Remove unnecessary kfree() call in rcu_free_wq()

From: Tejun Heo
Date: Wed May 27 2020 - 09:52:20 EST


On Wed, May 27, 2020 at 03:57:15PM +0800, qiang.zhang@xxxxxxxxxxxxx wrote:
> From: Zhang Qiang <qiang.zhang@xxxxxxxxxxxxx>
>
> The data structure member "wq->rescuer" was reset to a null pointer
> in one if branch. It was passed to a call of the function "kfree"
> in the callback function "rcu_free_wq" (which was eventually executed).
> The function "kfree" does not perform more meaningful data processing
> for a passed null pointer (besides immediately returning from such a call).
> Thus delete this function call which became unnecessary with the referenced
> software update.
>
> Fixes: def98c84b6cd ("workqueue: Fix spurious sanity check failures in destroy_workqueue()")
>
> Suggested-by: Markus Elfring <Markus.Elfring@xxxxxx>
> Signed-off-by: Zhang Qiang <qiang.zhang@xxxxxxxxxxxxx>

Applied to wq/for-5.8.

Thanks.

--
tejun