Mircea Damian wrote:
> 
> Hello,
> 
> I was expecting to receive some replies to my last desperate messages:
> http://www.mail-archive.com/linux-kernel@vger.kernel.org/msg35446.html
> http://www.mail-archive.com/linux-kernel@vger.kernel.org/msg36591.html
> 
> My machine is dyeing in add_timer(). It seems to happen only on SMP
> machines and is something related to the network driver. For some reason
>  one of the timer lists gets broken so we (we are two people trying to
>  solve this issue) wrote a "safe" timer.c which tries to rebuild the chain
>  in case it hits a NULL pointer.
> 
> The machine is (ofcourse) slower with this patch but at least it works.
> 
> Maybe someone can see which is the real bug and fix it.
> 
> Please help!

I found (at least part of) the problem.  In detach_timer() we test if
the timer is pending.  If it is not the function does not remove the
timer from the list and returns 0.  The functions that call
detach_timer() do not check the return value and unconditionally set the
list pointers to NULL, even though the timer is still on the list. 
Patch against 2.4.3 attached, but there may be a better solution.

-- 

						Brian Gerst