Re: [PATCH] posix-cpu-timers: remove lockdep_assert_irqs_disabled()

From: Sebastian Andrzej Siewior
Date: Mon Jun 11 2018 - 10:51:15 EST


On 2018-05-04 17:25:48 [+0200], To linux-kernel@xxxxxxxxxxxxxxx wrote:
> The lockdep_assert_irqs_disabled() was a BUG_ON() statement in the
> beginning and it was added just before the "spin_lock(siglock)"
> statement to ensure this lock was taken with disabled interrupts.
> This is no longer the case: the siglock is acquired via
> lock_task_sighand() and this function already disables the interrupts.
> The lock is also acquired before this "lockdep_assert_irqs_disabled" so
> it is beset to remove it.

*ping*

> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
> ---
> kernel/time/posix-cpu-timers.c | 2 --
> 1 file changed, 2 deletions(-)
>
> diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
> index 2541bd89f20e..d4f54df9c9fa 100644
> --- a/kernel/time/posix-cpu-timers.c
> +++ b/kernel/time/posix-cpu-timers.c
> @@ -604,7 +604,6 @@ static int posix_cpu_timer_set(struct k_itimer *timer, int timer_flags,
> /*
> * Disarm any old timer after extracting its expiry time.
> */
> - lockdep_assert_irqs_disabled();
>
> ret = 0;
> old_incr = timer->it.cpu.incr;
> @@ -1049,7 +1048,6 @@ static void posix_cpu_timer_rearm(struct k_itimer *timer)
> /*
> * Now re-arm for the new expiry time.
> */
> - lockdep_assert_irqs_disabled();
> arm_timer(timer);
> unlock:
> unlock_task_sighand(p, &flags);
> --
> 2.17.0