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Date: Sun, 3 May 2009 13:58:49 -0700 (PDT)
From: David Rientjes <rientjes@google.com>
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To: Cyrill Gorcunov <gorcunov@gmail.com>
cc: Pekka Enberg <penberg@cs.helsinki.fi>, Ingo Molnar <mingo@elte.hu>,
       Jack Steiner <steiner@sgi.com>,
       Andrew Morton <akpm@linux-foundation.org>,
       "H. Peter Anvin" <hpa@zytor.com>, Thomas Gleixner <tglx@linutronix.de>,
       LKML <linux-kernel@vger.kernel.org>,
       Christoph Lameter <cl@linux-foundation.org>
Subject: Re: introducing __GFP_PANIC
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On Mon, 4 May 2009, Cyrill Gorcunov wrote:

> @@ -1685,7 +1687,9 @@ nopage:
>  		dump_stack();
>  		show_mem();
>  	}
> -	return page;
> +	if (unlikely(gfp_mask & __GFP_PANIC))
> +		panic("Out of memory: panic due to __GFP_PANIC\n");
> +	return NULL;
>  got_pg:
>  	if (kmemcheck_enabled)
>  		kmemcheck_pagealloc_alloc(page, order, gfp_mask);
> 

If we really want a __GFP_PANIC flag for this purpose, I'd recommend also 
emitting the order and gfpmask in the panic() message since it may not be 
immediately obvious from the caller.