From: Petr Mladek <pmladek@xxxxxxxx> Subject: kthread: mark timer used by delayed kthread works as IRQ safe The timer used by delayed kthread works are IRQ safe because the used kthread_delayed_work_timer_fn() is IRQ safe. It is properly marked when initialized by KTHREAD_DELAYED_WORK_INIT(). But TIMER_IRQSAFE flag is missing when initialized by kthread_init_delayed_work(). The missing flag might trigger invalid warning from del_timer_sync() when kthread_mod_delayed_work() is called with interrupts disabled. This patch is result of a discussion about using the API, see https://lkml.kernel.org/r/cfa886ad-e3b7-c0d2-3ff8-58d94170eab5@xxxxxx Link: http://lkml.kernel.org/r/20200217120709.1974-1-pmladek@xxxxxxxx Signed-off-by: Petr Mladek <pmladek@xxxxxxxx> Reported-by: Grygorii Strashko <grygorii.strashko@xxxxxx> Tested-by: Grygorii Strashko <grygorii.strashko@xxxxxx> Acked-by: Tejun Heo <tj@xxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/kthread.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/include/linux/kthread.h~kthread-mark-timer-used-by-delayed-kthread-works-as-irq-safe +++ a/include/linux/kthread.h @@ -165,7 +165,8 @@ extern void __kthread_init_worker(struct do { \ kthread_init_work(&(dwork)->work, (fn)); \ timer_setup(&(dwork)->timer, \ - kthread_delayed_work_timer_fn, 0); \ + kthread_delayed_work_timer_fn, \ + TIMER_IRQSAFE); \ } while (0) int kthread_worker_fn(void *worker_ptr); _
