From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: Does KVM use one EPT table per Guest CR3? Date: Sun, 19 Dec 2010 16:31:49 +0200 Message-ID: <4D0E1755.6020407@redhat.com> References: <562744ED4DABB345A26E01CB5D34F5103192CFFE@BL2PRD0103MB033.prod.exchangelabs.com>,<4CFEADC0.9030002@codemonkey.ws> <562744ED4DABB345A26E01CB5D34F51031930BF9@BL2PRD0103MB033.prod.exchangelabs.com>,<4CFEB126.6070409@codemonkey.ws> <562744ED4DABB345A26E01CB5D34F51031930CCE@BL2PRD0103MB033.prod.exchangelabs.com>,<4D04A82F.4020808@redhat.com> <562744ED4DABB345A26E01CB5D34F51031935544@BL2PRD0103MB037.prod.exchangelabs.com> <4D0B80BC.3080700@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Anthony Liguori , "kvm@vger.kernel.org" To: Lok Kwong Yan Return-path: Received: from mx1.redhat.com ([209.132.183.28]:1025 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932105Ab0LSOcD (ORCPT ); Sun, 19 Dec 2010 09:32:03 -0500 In-Reply-To: <4D0B80BC.3080700@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On 12/17/2010 05:24 PM, Avi Kivity wrote: > On 12/17/2010 12:14 AM, Lok Kwong Yan wrote: >> Thanks for the reply and it makes a lot of sense. >> >> I am not seeing any EPT tables being zapped after the guest has fully >> started up although the value of EPTP continuously changes as the >> guest is running. > > Really strange, this is likely a bug. > I tried to reproduce, the only times I see eptp changes are when the guest reprograms the vga adapter: qemu-system-x86-20944 [033] 1327.151819: kvm_pio: pio_write at 0x3ce size 2 count 1 qemu-system-x86-20944 [033] 1327.151819: kvm_userspace_exit: reason KVM_EXIT_IO (2) qemu-system-x86-20944 [033] 1327.152405: kvm_mmu_prepare_zap_page: [FAILED TO PARSE] gfn=237568 role=122881 root_count=0 unsync=0 ... qemu-system-x86-20944 [033] 1327.153230: kvm_mmu_prepare_zap_page: [FAILED TO PARSE] gfn=0 role=253956 root_count=2 unsync=0 qemu-system-x86-20944 [033] 1327.153339: kvm_mmu_get_page: sp gfn 0 0/4 q0 direct --- !pge !nxe root 0sync qemu-system-x86-20944 [033] 1327.153344: print: a0265cde vmx_set_cr3: eptp fef14101 Under what scenario do you see eptp changing? -- error compiling committee.c: too many arguments to function