2022-12-05 10:21:07

by Yang Yingliang

Subject: [PATCH -next] w1: fix WARNING after calling w1_process()

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 <[email protected]>
---
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

2022-12-05 10:37:31

by Yang Yingliang

Subject: Re: [PATCH -next] w1: fix WARNING after calling w1_process()

Please ignore this patch, it's not for next.

On 2022/12/5 18:08, Yang Yingliang wrote:
> 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 <[email protected]>
> ---
> 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) {