public-mirrors/linux
1
0
Fork 0
mirror of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-08-05 16:54:27 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

wwan_hwsim: Avoid flush_scheduled_work() usage

Browse source 
Flushing system-wide workqueues is dangerous and will be forbidden.
Replace system_wq with local wwan_wq.

While we are at it, make err_clean_devs: label of wwan_hwsim_init()
behave like wwan_hwsim_exit(), for it is theoretically possible to call
wwan_hwsim_debugfs_devcreate_write()/wwan_hwsim_debugfs_devdestroy_write()
by the moment wwan_hwsim_init_devs() returns.

Link: https://lkml.kernel.org/r/49925af7-78a8-a3dd-bce6-cfc02e1a9236@I-love.SAKURA.ne.jp
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Reviewed-by: Loic Poulain <loic.poulain@linaro.org>
Link: https://lore.kernel.org/r/7390d51f-60e2-3cee-5277-b819a55ceabe@I-love.SAKURA.ne.jp
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Tetsuo Handa 2022-04-22 12:01:24 +09:00 • committed by Jakub Kicinski
parent df1cc21152
commit cc271ab866
1 changed files with 17 additions and 5 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

22
drivers/net/wwan/wwan_hwsim.c
View file

@ -33,6 +33,7 @@ static struct dentry *wwan_hwsim_debugfs_devcreate;
static DEFINE_SPINLOCK(wwan_hwsim_devs_lock);
static LIST_HEAD(wwan_hwsim_devs);
static unsigned int wwan_hwsim_dev_idx;
static struct workqueue_struct *wwan_wq;
struct wwan_hwsim_dev {
struct list_head list;
@ -371,7 +372,7 @@ static ssize_t wwan_hwsim_debugfs_portdestroy_write(struct file *file,
* waiting this callback to finish in the debugfs_remove() call. So,
* use workqueue.
*/
schedule_work(&port->del_work);
queue_work(wwan_wq, &port->del_work);
return count;
}
@ -416,7 +417,7 @@ static ssize_t wwan_hwsim_debugfs_devdestroy_write(struct file *file,
* waiting this callback to finish in the debugfs_remove() call. So,
* use workqueue.
*/
schedule_work(&dev->del_work);
queue_work(wwan_wq, &dev->del_work);
return count;
}
@ -506,9 +507,15 @@ static int __init wwan_hwsim_init(void)
if (wwan_hwsim_devsnum < 0 || wwan_hwsim_devsnum > 128)
return -EINVAL;
wwan_wq = alloc_workqueue("wwan_wq", 0, 0);
if (!wwan_wq)
return -ENOMEM;
wwan_hwsim_class = class_create(THIS_MODULE, "wwan_hwsim");
if (IS_ERR(wwan_hwsim_class))
return PTR_ERR(wwan_hwsim_class);
if (IS_ERR(wwan_hwsim_class)) {
err = PTR_ERR(wwan_hwsim_class);
goto err_wq_destroy;
}
wwan_hwsim_debugfs_topdir = debugfs_create_dir("wwan_hwsim", NULL);
wwan_hwsim_debugfs_devcreate =
@ -523,9 +530,13 @@ static int __init wwan_hwsim_init(void)
return 0;
err_clean_devs:
debugfs_remove(wwan_hwsim_debugfs_devcreate); /* Avoid new devs */
wwan_hwsim_free_devs();
flush_workqueue(wwan_wq); /* Wait deletion works completion */
debugfs_remove(wwan_hwsim_debugfs_topdir);
class_destroy(wwan_hwsim_class);
err_wq_destroy:
destroy_workqueue(wwan_wq);
return err;
}
@ -534,9 +545,10 @@ static void __exit wwan_hwsim_exit(void)
{
debugfs_remove(wwan_hwsim_debugfs_devcreate); /* Avoid new devs */
wwan_hwsim_free_devs();
flush_scheduled_work(); /* Wait deletion works completion */
flush_workqueue(wwan_wq); /* Wait deletion works completion */
debugfs_remove(wwan_hwsim_debugfs_topdir);
class_destroy(wwan_hwsim_class);
destroy_workqueue(wwan_wq);
}
module_init(wwan_hwsim_init);