From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B6AA9ECE560 for ; Mon, 17 Sep 2018 14:44:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7C5A62088F for ; Mon, 17 Sep 2018 14:44:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7C5A62088F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729001AbeIQULh (ORCPT ); Mon, 17 Sep 2018 16:11:37 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:60192 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728790AbeIQULg (ORCPT ); Mon, 17 Sep 2018 16:11:36 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 97F93ED1; Mon, 17 Sep 2018 07:43:57 -0700 (PDT) Received: from localhost.localdomain (unknown [10.4.13.81]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3D0903F5BD; Mon, 17 Sep 2018 07:43:55 -0700 (PDT) Subject: Re: [PATCH v5 18/18] kvm: arm64: Allow tuning the physical address size for VM To: Peter Maydell Cc: arm-mail-list , kvmarm@lists.cs.columbia.edu, kvm-devel , Marc Zyngier , Christoffer Dall , Eric Auger , Paolo Bonzini , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , Will Deacon , Catalin Marinas , James Morse , Dave P Martin , julien.grall@arm.com, lkml - Kernel Mailing List References: <20180917104144.19188-1-suzuki.poulose@arm.com> <20180917104144.19188-19-suzuki.poulose@arm.com> From: Suzuki K Poulose Message-ID: Date: Mon, 17 Sep 2018 15:43:53 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Peter, On 17/09/2018 15:20, Peter Maydell wrote: > On 17 September 2018 at 11:41, Suzuki K Poulose wrote: >> Allow specifying the physical address size limit for a new >> VM via the kvm_type argument for the KVM_CREATE_VM ioctl. This >> allows us to finalise the stage2 page table as early as possible >> and hence perform the right checks on the memory slots >> without complication. The size is ecnoded as Log2(PA_Size) in >> bits[7:0] of the type field. For backward compatibility the >> value 0 is reserved and implies 40bits. Also, lift the limit >> of the IPA to host limit and allow lower IPA sizes (e.g, 32). >> >> The userspace could check the extension KVM_CAP_ARM_VM_PHYS_SHIFT >> for the availability of this feature. The cap check returns the >> maximum limit for the physical address shift supported by the host. >> >> Cc: Marc Zyngier >> Cc: Christoffer Dall >> Cc: Peter Maydel > > Typo: my surname has two "l"s in it. Sorry about that. I have fixed this locally. Btw, did you get a chance to look at the patch itself ? If you did, are you fine with the API ? Suzuki