From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with ESMTP id A864C6B0096 for ; Thu, 24 Nov 2011 04:52:11 -0500 (EST) Date: Thu, 24 Nov 2011 09:52:06 +0000 From: Mel Gorman Subject: Re: [patch] mm, debug: test for online nid when allocating on single node Message-ID: <20111124095205.GQ19415@suse.de> References: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: David Rientjes Cc: Andrew Morton , linux-mm@kvack.org On Tue, Nov 22, 2011 at 05:26:05PM -0800, David Rientjes wrote: > Calling alloc_pages_exact_node() means the allocation only passes the > zonelist of a single node into the page allocator. If that node isn't > online, it's zonelist may never have been initialized causing a strange > oops that may not immediately be clear. > > I recently debugged an issue where node 0 wasn't online and an allocator > was passing 0 to alloc_pages_exact_node() and it resulted in a NULL > pointer on zonelist->_zoneref. If CONFIG_DEBUG_VM is enabled, though, it > would be nice to catch this a bit earlier. > > Signed-off-by: David Rientjes Acked-by: Mel Gorman Out of curiousity, who was passing in the ID of an offline node to alloc_pages_exact_node() ? -- Mel Gorman SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org