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Subject: Re: [PATCH] panic: Add sysctl/cmdline to dump all CPUs backtraces on
 oops event
To:     Andrew Morton <akpm@linux-foundation.org>,
        Randy Dunlap <rdunlap@infradead.org>
Cc:     linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
        mcgrof@kernel.org, keescook@chromium.org, yzaikin@google.com,
        tglx@linutronix.de, kernel@gpiccoli.net
References: <20200310163700.19186-1-gpiccoli@canonical.com>
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From:   "Guilherme G. Piccoli" <gpiccoli@canonical.com>
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Date:   Wed, 11 Mar 2020 09:46:45 -0300
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On 10/03/2020 22:26, Andrew Morton wrote:
> On Tue, 10 Mar 2020 13:59:15 -0700 Randy Dunlap <rdunlap@infradead.org> wrote:
> 
>>> +oops_all_cpu_backtrace:
>>> +================
>>> +
>>> +Determines if kernel should NMI all CPUs to dump their backtraces when
>>
>> I would much prefer that to be written without using NMI as a verb.
> 
> "Non maskably interrupt" ;)
> 
> I think it's OK.  Concise and the meaning is clear.

Hi Andrew, good idea heheh
Thank you and all that reviewed the grammar/wording, certainly I can
change that and resubmit.


> 
> 
> Why do we need the kernel boot parameter?  Isn't
> /proc/sys/kernel/oops_all_cpu_backtrace sufficient?
> 

I kept the kernel parameter as a consistency thing - every sysctl
"*_all_cpubacktrace" has a respective kernel parameter, so I did the
same (and if we get an oops booting a new kernel, this is maybe useful
depending on the point we get the oops). But if it's a problem for you,
I can remove the kernel parameter, your choice.

Cheers,


Guilherme