[PATCH v8] kernel, add panic_on_warn

Prarit Bhargava prarit at redhat.com
Sat Nov 8 05:29:21 PST 2014

On 11/07/2014 04:09 PM, David Rientjes wrote:
> On Fri, 7 Nov 2014, Prarit Bhargava wrote:
>> There very much is.  Consider a thread that hits a WARN() and then panics.  Then
>> somewhere in the panic code the thread hits another WARN() ... and then panics
>> again.  Previously this would have caused the system to "finish" panick'ing.
>> Now it makes the system hang.
> Then we're back to square one which is what is obviously the intent of 
> your patch and the comment that goes along with it: 

My original reply pointed out that the comment was wrong.

we want to clear
> panic_on_warn once and not allow multiple panic().  

On _this_ thread.  The multiple panic across threads cannot occur.

So why not just add
> the necessary synchronization to make sure that happens when WARN() 
> happens on two cpus simultaneously?

See above.



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