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Sender: Guenter Roeck <groeck7@gmail.com>
Date:   Fri, 4 Nov 2022 09:14:45 -0700
From:   Guenter Roeck <linux@roeck-us.net>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
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        Jesse Brandeburg <jesse.brandeburg@intel.com>,
        Tony Nguyen <anthony.l.nguyen@intel.com>,
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        Mirko Lindner <mlindner@marvell.com>,
        Stephen Hemminger <stephen@networkplumber.org>,
        Martin KaFai Lau <martin.lau@kernel.org>,
        Alexei Starovoitov <ast@kernel.org>,
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Subject: Re: [RFC][PATCH v2 19/31] timers: net: Use del_timer_shutdown()
 before freeing timer
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On Fri, Nov 04, 2022 at 01:51:39AM -0400, Steven Rostedt wrote:
> On Thu, 3 Nov 2022 17:00:20 -0700
> Eric Dumazet <edumazet@google.com> wrote:
> 
> >  inet_csk_clear_xmit_timers() can be called multiple times during TCP
> > socket lifetime.
> > 
> > (See tcp_disconnect(), which can be followed by another connect() ... and loop)
> > 
> > Maybe add a second parameter, or add a new
> > inet_csk_shutdown_xmit_timers() only called from tcp_v4_destroy_sock() ?
> > 
> 
> I guess.
> 
> > >
> > >  void inet_csk_delete_keepalive_timer(struct sock *sk)
> > >  {
> > > -       sk_stop_timer(sk, &sk->sk_timer);
> > > +       sk_shutdown_timer(sk, &sk->sk_timer);  
> > 
> > SO_KEEPALIVE can be called multiple times in a TCP socket lifetime,
> > on/off/on/off/...
> > 
> > I suggest leaving sk_stop_timer() here.
> > 
> > Eventually  inet_csk_clear_xmit_timers( sk, destroy=true) (or
> > inet_csk_shutdown_xmit_timers(())
> >    will  be called before the socket is destroyed.
> 
> OK. 
> 
> Guenter,
> 
> I posted a new series, but did not include this change. If you want to
> test that other series, I would suggest to at least add the first part
> of this patch, otherwise it will trigger. But we want to see if there's
> other locations of issue that we should care about.
> 

I'll run a test on the other series without change first. We'll see what
happens. If necessary I'll add [parts of] this patch and re-test, but
before doing that I would like to get a sense for the status of your
series as-is.

Thanks,
Guenter