From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Zyngier Subject: Re: [PATCH] arm64/kvm: Add generic v8 KVM target Date: Fri, 03 Jul 2015 09:28:23 +0100 Message-ID: <559647A7.7010309@arm.com> References: <1434531646-4873-1-git-send-email-suzuki.poulose@arm.com> <558A6A84.5020603@arm.com> <20150624085128.GA22785@cbox> <558A7936.7020109@arm.com> <20150625123034.GE28244@cbox> <558BF6C9.3000009@arm.com> <558C05A9.8080201@arm.com> <20150626095318.GG28244@cbox> <559180CA.3050905@arm.com> <559185D4.7060308@arm.com> <85D36B67-643B-407F-944F-D18D54FF9909@caviumnetworks.com> <559642EE.1050605@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel , "timur@codeaurora.org" , "Chalamarla, Tirumalesh" , arm-mail-list , "vgandhi@codeaurora.org" , "kvmarm@lists.cs.columbia.edu" To: Peter Maydell Return-path: In-Reply-To: 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 List-Id: kvm.vger.kernel.org On 03/07/15 09:12, Peter Maydell wrote: > On 3 July 2015 at 09:08, Marc Zyngier wrote: >> On 02/07/15 21:29, Chalamarla, Tirumalesh wrote: >>> is there a chance that this get merged in to 4.2? if not is it possible >>> to accept the other patches like adding implementations explicitly(like >>> Thunder). >> >> We first need to reach a conclusion on this. Until then, I don't plan to >> get anything in. As for 4.2, it feels way too late (the merge window is >> almost closed now). > > I would still like to see the proponents of this patch say > what their model is for userspace support of cross-host migration, > if we're abandoning the model the current API envisages. I thought we had discussed this above, and don't really see this as a departure from the current model: - "-cpu host" results in "GENERIC" being used: VM can only be migrated to the exact same HW (no cross-host migration). MIDR should probably become RO. - "-cpu host" results in "A57" (for example): VM can be migrated to a variety of A57 platforms, and allow for some fuzzing on the revision (or accept any revision). - "-cpu a57" forces an A57 model to be emulated, always. It is always possible to migrate such a VM on any host. I think only the first point is new, but the last two are what we have (or what we should have). Does it answer your concerns, or did you have something else in mind? 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: Fri, 03 Jul 2015 09:28:23 +0100 Subject: [PATCH] arm64/kvm: Add generic v8 KVM target In-Reply-To: References: <1434531646-4873-1-git-send-email-suzuki.poulose@arm.com> <558A6A84.5020603@arm.com> <20150624085128.GA22785@cbox> <558A7936.7020109@arm.com> <20150625123034.GE28244@cbox> <558BF6C9.3000009@arm.com> <558C05A9.8080201@arm.com> <20150626095318.GG28244@cbox> <559180CA.3050905@arm.com> <559185D4.7060308@arm.com> <85D36B67-643B-407F-944F-D18D54FF9909@caviumnetworks.com> <559642EE.1050605@arm.com> Message-ID: <559647A7.7010309@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 03/07/15 09:12, Peter Maydell wrote: > On 3 July 2015 at 09:08, Marc Zyngier wrote: >> On 02/07/15 21:29, Chalamarla, Tirumalesh wrote: >>> is there a chance that this get merged in to 4.2? if not is it possible >>> to accept the other patches like adding implementations explicitly(like >>> Thunder). >> >> We first need to reach a conclusion on this. Until then, I don't plan to >> get anything in. As for 4.2, it feels way too late (the merge window is >> almost closed now). > > I would still like to see the proponents of this patch say > what their model is for userspace support of cross-host migration, > if we're abandoning the model the current API envisages. I thought we had discussed this above, and don't really see this as a departure from the current model: - "-cpu host" results in "GENERIC" being used: VM can only be migrated to the exact same HW (no cross-host migration). MIDR should probably become RO. - "-cpu host" results in "A57" (for example): VM can be migrated to a variety of A57 platforms, and allow for some fuzzing on the revision (or accept any revision). - "-cpu a57" forces an A57 model to be emulated, always. It is always possible to migrate such a VM on any host. I think only the first point is new, but the last two are what we have (or what we should have). Does it answer your concerns, or did you have something else in mind? M. -- Jazz is not dead. It just smells funny...