From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Zyngier Subject: Re: [RFC v2 05/10] KVM: arm/arm64: Initialize the emulated EL1 physical timer Date: Wed, 1 Feb 2017 10:08:01 +0000 Message-ID: <619cc856-b268-df3b-d064-e511fa54afe0@arm.com> References: <1485479100-4966-1-git-send-email-jintack@cs.columbia.edu> <1485479100-4966-6-git-send-email-jintack@cs.columbia.edu> <86wpde83xn.fsf@arm.com> <20170130145816.GC16459@cbox> <57b57b31-b8ad-f5c8-a1fc-4cde9a564dd2@arm.com> <20170130190450.GF16459@cbox> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 070DE40692 for ; Wed, 1 Feb 2017 05:07:46 -0500 (EST) Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id PVlOX9p8cedN for ; Wed, 1 Feb 2017 05:07:45 -0500 (EST) Received: from foss.arm.com (foss.arm.com [217.140.101.70]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 2EE6B40284 for ; Wed, 1 Feb 2017 05:07:44 -0500 (EST) In-Reply-To: <20170130190450.GF16459@cbox> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu To: Christoffer Dall Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, catalin.marinas@arm.com, will.deacon@arm.com, linux@armlinux.org.uk, kvmarm@lists.cs.columbia.edu, andre.przywara@arm.com, pbonzini@redhat.com, linux-arm-kernel@lists.infradead.org List-Id: kvmarm@lists.cs.columbia.edu On 30/01/17 19:04, Christoffer Dall wrote: > On Mon, Jan 30, 2017 at 05:44:20PM +0000, Marc Zyngier wrote: >> Wventually, we'll have to support an offset-able >> physical counter to support nested virtualization, but this can come at >> a later time. >> > Why do we need the offset-able physical counter for nested > virtualization? I would think for nested virt we just need to support > respecting how the guest hypervisor programs CNTVOFF? Ah, I see what you mean. Yes, once the guest hypervisor is in control of its own CNTVOFF, we get everything we need. So let's just ignore this for the time being, and we should be pretty good for this series. Thanks, M. -- Jazz is not dead. It just smells funny... From mboxrd@z Thu Jan 1 00:00:00 1970 From: marc.zyngier@arm.com (Marc Zyngier) Date: Wed, 1 Feb 2017 10:08:01 +0000 Subject: [RFC v2 05/10] KVM: arm/arm64: Initialize the emulated EL1 physical timer In-Reply-To: <20170130190450.GF16459@cbox> References: <1485479100-4966-1-git-send-email-jintack@cs.columbia.edu> <1485479100-4966-6-git-send-email-jintack@cs.columbia.edu> <86wpde83xn.fsf@arm.com> <20170130145816.GC16459@cbox> <57b57b31-b8ad-f5c8-a1fc-4cde9a564dd2@arm.com> <20170130190450.GF16459@cbox> Message-ID: <619cc856-b268-df3b-d064-e511fa54afe0@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 30/01/17 19:04, Christoffer Dall wrote: > On Mon, Jan 30, 2017 at 05:44:20PM +0000, Marc Zyngier wrote: >> Wventually, we'll have to support an offset-able >> physical counter to support nested virtualization, but this can come at >> a later time. >> > Why do we need the offset-able physical counter for nested > virtualization? I would think for nested virt we just need to support > respecting how the guest hypervisor programs CNTVOFF? Ah, I see what you mean. Yes, once the guest hypervisor is in control of its own CNTVOFF, we get everything we need. So let's just ignore this for the time being, and we should be pretty good for this series. Thanks, M. -- Jazz is not dead. It just smells funny... From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751934AbdBAKIN (ORCPT ); Wed, 1 Feb 2017 05:08:13 -0500 Received: from foss.arm.com ([217.140.101.70]:56056 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751406AbdBAKIL (ORCPT ); Wed, 1 Feb 2017 05:08:11 -0500 Subject: Re: [RFC v2 05/10] KVM: arm/arm64: Initialize the emulated EL1 physical timer To: Christoffer Dall References: <1485479100-4966-1-git-send-email-jintack@cs.columbia.edu> <1485479100-4966-6-git-send-email-jintack@cs.columbia.edu> <86wpde83xn.fsf@arm.com> <20170130145816.GC16459@cbox> <57b57b31-b8ad-f5c8-a1fc-4cde9a564dd2@arm.com> <20170130190450.GF16459@cbox> Cc: Jintack Lim , pbonzini@redhat.com, rkrcmar@redhat.com, linux@armlinux.org.uk, catalin.marinas@arm.com, will.deacon@arm.com, andre.przywara@arm.com, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org, Peter Maydell From: Marc Zyngier Organization: ARM Ltd Message-ID: <619cc856-b268-df3b-d064-e511fa54afe0@arm.com> Date: Wed, 1 Feb 2017 10:08:01 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Icedove/45.5.1 MIME-Version: 1.0 In-Reply-To: <20170130190450.GF16459@cbox> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 30/01/17 19:04, Christoffer Dall wrote: > On Mon, Jan 30, 2017 at 05:44:20PM +0000, Marc Zyngier wrote: >> Wventually, we'll have to support an offset-able >> physical counter to support nested virtualization, but this can come at >> a later time. >> > Why do we need the offset-able physical counter for nested > virtualization? I would think for nested virt we just need to support > respecting how the guest hypervisor programs CNTVOFF? Ah, I see what you mean. Yes, once the guest hypervisor is in control of its own CNTVOFF, we get everything we need. So let's just ignore this for the time being, and we should be pretty good for this series. Thanks, M. -- Jazz is not dead. It just smells funny...