From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Gleixner <tglx@linutronix.de>
Subject: Re: Soft lockup issue in Linux 4.1.9
Date: Fri, 2 Oct 2015 23:04:29 +0200 (CEST)
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Cc: Eric Dumazet <edumazet@google.com>,
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To: Eric Dumazet <eric.dumazet@gmail.com>
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On Fri, 2 Oct 2015, Eric Dumazet wrote:
> On Fri, 2015-10-02 at 22:04 +0200, Thomas Gleixner wrote:
> 
> > What makes sure, that the timer cannot be readded while that timer
> > callback is running?
> 
> What is exactly your question ?

CPU0   	  	       		CPU1

timer expires
  callback
				add timer
  timer_pending() == true
  ===> del_timer_sync()

I was just curious how this is prevented as I got lost in the
networking code as usual :)

Thanks,

	tglx