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From: <qiang.zhang@windriver.com>
To: <tj@kernel.org>
Cc: <jiangshanlai@gmail.com>, <markus.elfring@web.de>,
	<linux-kernel@vger.kernel.org>
Subject: [PATCH v5] workqueue: Remove unnecessary kfree() call in rcu_free_wq()
Date: Wed, 27 May 2020 15:57:15 +0800	[thread overview]
Message-ID: <20200527075715.36849-1-qiang.zhang@windriver.com> (raw)

From: Zhang Qiang <qiang.zhang@windriver.com>

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@web.de> 
Signed-off-by: Zhang Qiang <qiang.zhang@windriver.com>
---
 v1->v2->v3->v4->v5:
 Modify weakly submitted information.

 kernel/workqueue.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 891ccad5f271..a2451cdcd503 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -3491,7 +3491,6 @@ static void rcu_free_wq(struct rcu_head *rcu)
 	else
 		free_workqueue_attrs(wq->unbound_attrs);
 
-	kfree(wq->rescuer);
 	kfree(wq);
 }
 
-- 
2.24.1


             reply	other threads:[~2020-05-27  7:48 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-27  7:57 qiang.zhang [this message]
2020-05-27  8:20 ` [PATCH v5] workqueue: Remove unnecessary kfree() call in rcu_free_wq() Markus Elfring
     [not found]   ` <DM6PR11MB32573F3884A864ECD586235EFF8E0@DM6PR11MB3257.namprd11.prod.outlook.com>
2020-05-28  1:44     ` 回复: " Zhang, Qiang
2020-05-28  9:57       ` Dan Carpenter
2020-05-28 10:38         ` Tejun Heo
2020-05-28 11:00           ` [v5] " Markus Elfring
2020-05-28 14:40             ` Markus Elfring
2020-05-28 12:08         ` 回复: [PATCH v5] " Lai Jiangshan
2020-05-28 12:25           ` Dan Carpenter
2020-05-28 13:27             ` Lai Jiangshan
2020-05-28 14:03               ` Tejun Heo
2020-05-28 14:45                 ` [v5] " Markus Elfring
2020-05-28 14:06               ` 回复: [PATCH v5] " Dan Carpenter
2020-05-28 15:25             ` [v5] " Markus Elfring
2020-05-28 15:02           ` Markus Elfring
2020-05-28 15:02           ` Markus Elfring
2020-05-27 13:52 ` [PATCH v5] " Tejun Heo
2020-05-28  1:29 qiang.zhang

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