From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gleb Natapov Subject: Re: [PATCH] KVM: nVMX: Advertise IA32_PAT in VM exit control Date: Mon, 5 Aug 2013 13:55:00 +0300 Message-ID: <20130805105500.GA10891@redhat.com> References: <1375693835-10988-1-git-send-email-yzt356@gmail.com> <20130805093349.GI2258@redhat.com> <51FF80A8.5000309@web.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Gmail , "kvm@vger.kernel.org" , "pbonzini@redhat.com" To: Jan Kiszka Return-path: Received: from mx1.redhat.com ([209.132.183.28]:20169 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754089Ab3HEKzE (ORCPT ); Mon, 5 Aug 2013 06:55:04 -0400 Content-Disposition: inline In-Reply-To: <51FF80A8.5000309@web.de> Sender: kvm-owner@vger.kernel.org List-ID: On Mon, Aug 05, 2013 at 12:38:32PM +0200, Jan Kiszka wrote: > On 2013-08-05 11:36, Gmail wrote: > > > > > >> On Mon, Aug 05, 2013 at 05:10:35PM +0800, Arthur Chunqi Li wrote: > >>> Advertise VM_EXIT_SAVE_IA32_PAT and VM_EXIT_LOAD_IA32_PAT. > >>> > >>> Signed-off-by: Arthur Chunqi Li > >>> --- > >>> arch/x86/kvm/vmx.c | 3 ++- > >>> 1 file changed, 2 insertions(+), 1 deletion(-) > >>> > >>> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c > >>> index 45fd70c..240f0db 100644 > >>> --- a/arch/x86/kvm/vmx.c > >>> +++ b/arch/x86/kvm/vmx.c > >>> @@ -2198,7 +2198,8 @@ static __init void nested_vmx_setup_ctls_msrs(void) > >>> #else > >>> nested_vmx_exit_ctls_high = 0; > >>> #endif > >>> - nested_vmx_exit_ctls_high |= VM_EXIT_ALWAYSON_WITHOUT_TRUE_MSR; > >>> + nested_vmx_exit_ctls_high |= VM_EXIT_ALWAYSON_WITHOUT_TRUE_MSR | > >>> + VM_EXIT_LOAD_IA32_PAT | VM_EXIT_SAVE_IA32_PAT; > >>> > >> You should not set those if host does not support them, otherwise > >> GUEST_IA32_PAT may not be available > > To Jan, > > Is this different from IA32_EFER? > > As we use a real VMCS to keep GUEST/HOST_IA32_EFER, we actually do > depend on the existence of the host feature. So my patch requires an > update as you noted. > Your patch didn't add new users of GUEST_IA32_PAT and VM_ENTRY_LOAD_IA32_PAT is enabled by nested only if host has it, so I am not sure why you are saying that patch should be updated. -- Gleb.