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From:   Yang Yingliang <yangyingliang@huawei.com>
To:     <linux-kernel@vger.kernel.org>
CC:     <david@fries.net>, <gregkh@linuxfoundation.org>
Subject: [PATCH] w1: fix WARNING after calling w1_process()
Date:   Mon, 5 Dec 2022 18:15:58 +0800
Message-ID: <20221205101558.3599162-1-yangyingliang@huawei.com>
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I got the following WARNING message while removing driver(ds2482):

------------[ cut here ]------------
do not call blocking ops when !TASK_RUNNING; state=1 set at [<000000002d50bfb6>] w1_process+0x9e/0x1d0 [wire]
WARNING: CPU: 0 PID: 262 at kernel/sched/core.c:9817 __might_sleep+0x98/0xa0
CPU: 0 PID: 262 Comm: w1_bus_master1 Tainted: G                 N 6.1.0-rc3+ #307
RIP: 0010:__might_sleep+0x98/0xa0
Call Trace:
 exit_signals+0x6c/0x550
 do_exit+0x2b4/0x17e0
 kthread_exit+0x52/0x60
 kthread+0x16d/0x1e0
 ret_from_fork+0x1f/0x30

The state of task is set to TASK_INTERRUPTIBLE in loop in w1_process(),
set it to TASK_RUNNING when it breaks out of the loop to avoid the
warning.

Fixes: 3c52e4e62789 ("W1: w1_process, block or sleep")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
---
 drivers/w1/w1.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c
index 8b35fae4cd61..4a2ddf730a3a 100644
--- a/drivers/w1/w1.c
+++ b/drivers/w1/w1.c
@@ -1195,8 +1195,10 @@ int w1_process(void *data)
 		 */
 		mutex_unlock(&dev->list_mutex);
 
-		if (kthread_should_stop())
+		if (kthread_should_stop()) {
+			__set_current_state(TASK_RUNNING);
 			break;
+		}
 
 		/* Only sleep when the search is active. */
 		if (dev->search_count) {
-- 
2.25.1