From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with SMTP id 762606B00F3 for ; Wed, 8 Jun 2011 05:38:29 -0400 (EDT) Date: Wed, 8 Jun 2011 11:38:27 +0200 From: Michal Hocko Subject: Re: [PATCH 2/4] mm: vmscan: Do not use page_count without a page pin Message-ID: <20110608093827.GD6742@tiehlicka.suse.cz> References: <1307459225-4481-1-git-send-email-mgorman@suse.de> <1307459225-4481-3-git-send-email-mgorman@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1307459225-4481-3-git-send-email-mgorman@suse.de> Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: Andrew Morton , Andrea Arcangeli , Minchan Kim , Thomas Sattler , Ury Stankevich , Andi Kleen , linux-mm , linux-kernel On Tue 07-06-11 16:07:03, Mel Gorman wrote: > From: Andrea Arcangeli > > From: Andrea Arcangeli > > It is unsafe to run page_count during the physical pfn scan because > compound_head could trip on a dangling pointer when reading > page->first_page if the compound page is being freed by another CPU. > > [mgorman@suse.de: Split out patch] > Signed-off-by: Andrea Arcangeli > Signed-off-by: Mel Gorman Reviewed-by: Michal Hocko -- Michal Hocko SUSE Labs SUSE LINUX s.r.o. Lihovarska 1060/12 190 00 Praha 9 Czech Republic -- 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