From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx125.postini.com [74.125.245.125]) by kanga.kvack.org (Postfix) with SMTP id 022F16B0006 for ; Thu, 17 Jan 2013 16:22:19 -0500 (EST) Date: Thu, 17 Jan 2013 21:22:18 +0000 From: Christoph Lameter Subject: Re: [RFC][PATCH] slub: Check for page NULL before doing the node_match check In-Reply-To: <1358446258.23211.32.camel@gandalf.local.home> Message-ID: <0000013c4a64146b-68cd6f7d-f7e2-460b-9ee5-d931714ce062-000000@email.amazonses.com> References: <1358446258.23211.32.camel@gandalf.local.home> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Steven Rostedt Cc: LKML , linux-mm , Andrew Morton , Pekka Enberg , Matt Mackall , Thomas Gleixner , RT , Clark Williams , John Kacur , "Luis Claudio R. Goncalves" On Thu, 17 Jan 2013, Steven Rostedt wrote: > Anyway, looking at where this crashed, it seems that the page variable > can be NULL when passed to the node_match() function (which does not > check if it is NULL). When this happens we get the above panic. > > As page is only used in slab_alloc() to check if the node matches, if > it's NULL I'm assuming that we can say it doesn't and call the > __slab_alloc() code. Is this a correct assumption? c->page should only be NULL when c->freelist == NULL but obviously there are race conditions where c->freelist may not have been zapped but c->page was. -- 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/ . Don't email: email@kvack.org