Commit 4b7a1304 authored Jul 25, 2008 by Oleg Nesterov Committed by Linus Torvalds Jul 25, 2008

posix timers: timer_delete: remove the bogus "->it_process != NULL" check



sys_timer_delete() and itimer_delete() check "timer->it_process != NULL",
this looks completely bogus.  ->it_process == NULL means that this timer
is already under destruction or it is not fully initialized, this must not
happen.

	sys_timer_delete: the timer is locked, and lock_timer() can't succeed
	if ->it_process == NULL.

	itimer_delete: it is called by exit_itimers() when there are no other
	threads which can play with signal_struct->posix_timers.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent da5ef6bb

kernel/posix-timers.c

+8 −10

Original line number	Diff line number	Diff line
		@@ -856,11 +856,10 @@ retry_delete:
		* This keeps any tasks waiting on the spin lock from thinking
		* they got something (see the lock code above).
		*/
		if (timer->it_process) {
		if (timer->it_sigev_notify == (SIGEV_SIGNAL\|SIGEV_THREAD_ID))
		put_task_struct(timer->it_process);
		timer->it_process = NULL;
		}

		unlock_timer(timer, flags);
		release_posix_timer(timer, IT_ID_SET);
		return 0;
		@@ -885,11 +884,10 @@ retry_delete:
		* This keeps any tasks waiting on the spin lock from thinking
		* they got something (see the lock code above).
		*/
		if (timer->it_process) {
		if (timer->it_sigev_notify == (SIGEV_SIGNAL\|SIGEV_THREAD_ID))
		put_task_struct(timer->it_process);
		timer->it_process = NULL;
		}

		unlock_timer(timer, flags);
		release_posix_timer(timer, IT_ID_SET);
		}

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