Re: del_timer_sync needed for UP RT systems.

From: George Anzinger
Date: Tue Apr 26 2005 - 19:38:10 EST

Daniel Walker wrote:
On Tue, 2005-04-26 at 17:14, George Anzinger wrote:

The problem here is that the reference is to timr, a pointer to something which has been deleted. The memory may well be used elsewhere by this time which will make the test of it_process wrong. It also means we could mess with someone elses memory in the memset above.

Bottom line, you can use sys_timer_delete() on a timer, and trigger the
same timer your deleting .. Those operations should be serialized, which
they currently aren't ..

I agree. The change to do this is to use the del_timer_sync() or the del_singleshot_timer() code.

It is possible and desirable to be able to delete a running timer. We don't want to take it away from the timer call back routine, however, as that leads to "bad things". That is why these two del_* routines were written.

George Anzinger george@xxxxxxxxxx
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