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Date: Tue, 20 Mar 2007 11:43:56 -0600
From: "Chris Friesen" <cfriesen@nortel.com>
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To: linux-kernel@vger.kernel.org
Subject: how to purposfully fragment memory?
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I'm trying to test code paths dealing with fragmented memory, so I'd 
like to have a simple way to cause fragmented memory in the kernel.  Is 
there any API in the kernel that would let me allocate two contiguous 
pages, then free one of them?


I tried the following, but it triggers an oops in free_page():

unsigned long addr =
	__get_free_pages(GFP_KERNEL|__GFP_NORETRY|__GFP_NOWARN, 1);
if (!addr)
	break;
free_page(addr+4096);


Thanks,

Chris