From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757017AbaDVUEz (ORCPT ); Tue, 22 Apr 2014 16:04:55 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:53224 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750837AbaDVUEx (ORCPT ); Tue, 22 Apr 2014 16:04:53 -0400 Date: Tue, 22 Apr 2014 22:04:49 +0200 From: Peter Zijlstra To: Andrew Morton Cc: Jiang Liu , Ingo Molnar , Ingo Molnar , "Rafael J . Wysocki" , Tony Luck , linux-kernel@vger.kernel.org Subject: Re: [Bugfix] sched: fix possible invalid memory access caused by CPU hot-addition Message-ID: <20140422200449.GF11096@twins.programming.kicks-ass.net> References: <1398144435-26271-1-git-send-email-jiang.liu@linux.intel.com> <20140422081515.GF11182@twins.programming.kicks-ass.net> <20140422130151.83bc4539364ca660c68de859@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140422130151.83bc4539364ca660c68de859@linux-foundation.org> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 22, 2014 at 01:01:51PM -0700, Andrew Morton wrote: > On Tue, 22 Apr 2014 10:15:15 +0200 Peter Zijlstra wrote: > > > On Tue, Apr 22, 2014 at 01:27:15PM +0800, Jiang Liu wrote: > > > When calling kzalloc_node(size, flags, node), we should first check > > > whether node is onlined, otherwise it may cause invalid memory access > > > as below. > > > > But this is only for memory less node crap, right? > > um, why are memoryless nodes crap? Why wouldn't they be? Having CPUs with no local memory seems decidedly suboptimal.