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Date:   Sat, 5 Nov 2022 23:12:41 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Julia Lawall <julia.lawall@inria.fr>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        linux-kernel@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>,
        Stephen Boyd <sboyd@kernel.org>,
        Guenter Roeck <linux@roeck-us.net>,
        Anna-Maria Gleixner <anna-maria@linutronix.de>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH v4a 00/38] timers: Use timer_shutdown*() before freeing
 timers
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On Sun, 6 Nov 2022 11:05:14 +0800 (+08)
Julia Lawall <julia.lawall@inria.fr> wrote:

> > Thinking that's what you meant (examples would be easier to understand,
> > than descriptions). And it didn't cover the return case. Does it only
> > cover gotos?
> >
> >   See drivers/net/wireless/intel/iwlwifi/mvm/sta.c for the false positive case:
> >
> > 	del_timer_sync(&baid_data->session_timer);
> > [..]  
> 
> But there is a kfree_rcu(baid_data, rcu_head); right below.  So it looks
> fine?

D'oh! I think you are correct. I didn't trust the script and it appears
that it was correct all along. The free was hidden in between the code
and I only noticed the kfree() in the error path. I thought that was a
bug in the script. :-/

I guess there were no false positives then. To be sure, I'll write a
script to find all that have a return or goto in between and see what
it comes up with.

I guess my original patch doesn't need any changes from the script.
I'll look more.

Thanks Julia!

-- Steve