Re: [PATCH] posix-timer: fix deletion race

[Thomas Gleixner <tglx@linutronix.de>]

On Tue, 2007-07-17 at 17:07 +0400, Oleg Nesterov wrote:
> I think we can make a simpler patch,
> 
> --- posix-timers.c~	2007-06-29 14:45:04.000000000 +0400
> +++ posix-timers.c	2007-07-17 16:59:45.000000000 +0400
> @@ -449,6 +449,9 @@ static void release_posix_timer(struct k
>  		idr_remove(&posix_timers_id, tmr->it_id);
>  		spin_unlock_irqrestore(&idr_lock, flags);
>  	}
> +
> +	spin_unlock_wait(tmr->it_lock);
> +
>  	sigqueue_free(tmr->sigq);
>  	if (unlikely(tmr->it_process) &&
>  	    tmr->it_sigev_notify == (SIGEV_SIGNAL|SIGEV_THREAD_ID))
> 
> 
> What do you think? Instead of complicating the lock_timer(), release_posix_timer()
> just makes sure that nobody can "use" tmr.

Hmm, I prefer to fix that at the place where the race actually happens. 

	tglx