From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH v2 5/5] KVM: MMU: retry #PF for softmmu Date: Mon, 15 Nov 2010 11:59:11 +0200 Message-ID: <4CE1046F.8060100@redhat.com> References: <4CDCE2B0.7000601@cn.fujitsu.com> <4CDCE3C2.9030107@cn.fujitsu.com> <4CDFBE00.2000802@redhat.com> <4CE0C45C.809@cn.fujitsu.com> <4CE0FDBC.20505@redhat.com> <4CE1038D.9020403@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , Gleb Natapov , LKML , KVM To: Xiao Guangrong Return-path: In-Reply-To: <4CE1038D.9020403@cn.fujitsu.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 11/15/2010 11:55 AM, Xiao Guangrong wrote: > >> > Or another thread may have mmap()ed something else over the > >> > same address. > >> > >> The mmap virtual address is also visible for other threads since the > >> threads > >> have the same page table, so i think this case is the same as above? > > > > Again, don't we install the wrong spte in this case? > > > > I think it doesn't corrupts spte since we will walk guest page table again > and map it to shadow pages when we retry #PF. Well, you're right, we don't use any gfn/pfn info from the async page fault. However, we're still not modelling the cpu accurately. For example we will set dirty and accessed bits, or inject a page fault if the gpte turns out to be not present. -- error compiling committee.c: too many arguments to function