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Date:   Tue, 11 Apr 2023 22:32:06 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     "Tze-nan Wu (=?UTF-8?B?5ZCz5r6k5Y2X?=)" <Tze-nan.Wu@mediatek.com>
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Subject: Re: [PATCH v3] ring-buffer: Prevent inconsistent operation on
 cpu_buffer->resize_disabled
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On Wed, 12 Apr 2023 02:27:53 +0000
Tze-nan Wu (吳澤南) <Tze-nan.Wu@mediatek.com> wrote:

> > > @@ -5368,7 +5372,7 @@ void ring_buffer_reset_online_cpus(struct
> > > trace_buffer *buffer)
> > >       /* Make sure all commits have finished */
> > >       synchronize_rcu();
> > > 
> > > -     for_each_online_buffer_cpu(buffer, cpu) {
> > > +     for_each_cpu_and(cpu, buffer->cpumask, &reset_online_cpumask)  
> 
> Maybe we should use for_each_buffer_cpu(buffer, cpu) here?
> since a CPU may also came offline during synchronize_rcu().

Yeah, I guess that works too (not looking at the code at the moment though).

-- Steve

> 
> > > {
> > >               cpu_buffer = buffer->buffers[cpu];  
> >