Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750851Ab0DNEBQ (ORCPT ); Wed, 14 Apr 2010 00:01:16 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:55642 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1750704Ab0DNEBP (ORCPT ); Wed, 14 Apr 2010 00:01:15 -0400 Message-ID: <4BC53D6B.6020501@cn.fujitsu.com> Date: Wed, 14 Apr 2010 11:58:35 +0800 From: Xiao Guangrong User-Agent: Thunderbird 2.0.0.24 (Windows/20100228) MIME-Version: 1.0 To: Marcelo Tosatti CC: Avi Kivity , KVM list , LKML Subject: Re: [PATCH 3/6] KVM MMU: optimize/cleanup for marking parent unsync References: <4BC2D2E2.1030604@cn.fujitsu.com> <4BC2D390.7050708@cn.fujitsu.com> <20100412171211.GC4976@amt.cnet> <4BC3CE83.8020705@cn.fujitsu.com> <20100413150137.GB24128@amt.cnet> <4BC5353A.30509@cn.fujitsu.com> In-Reply-To: <4BC5353A.30509@cn.fujitsu.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 687 Lines: 23 Xiao Guangrong wrote: > > Actually, the origin code has a bug, the code segment in mmu_parent_walk(): > > | if (!sp->multimapped && sp->parent_pte) { > | ...... > | return; > | } > | hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link) > | for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i) { > | ...... > | } > > So, if sp->parent_pte == NULL, it's unsafe... Marcelo, please ignore this, it not a bug, just my mistake, sorry... -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/