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Date: Thu, 6 Nov 2014 17:07:31 -0500
From: Vivek Goyal <vgoyal@redhat.com>
To: David Rientjes <rientjes@google.com>
Cc: Prarit Bhargava <prarit@redhat.com>, linux-kernel@vger.kernel.org,
        Jonathan Corbet <corbet@lwn.net>,
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Subject: Re: [PATCH v8] kernel, add panic_on_warn
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On Thu, Nov 06, 2014 at 01:57:36PM -0800, David Rientjes wrote:

[..]
> You see that doing
> 
> 	if (panic_on_warn) {
> 		panic_on_warn = 0;
> 		panic(...);
> 	}
> 
> is racy, I hope.  If two threads WARN() at the same time, then there's 
> nothing preventing a double panic() because WARN() itself is not 
> serialized against anything.  So both the current comment and your 
> suggested revision comment are bogus.

panic() is serialized on panic_lock. So I guess it is fine to hit WARN()
on multiple cpus. Do you see an issue there?

Thanks
Vivek