From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Fedin Subject: RE: [PATCH 0/3] KVM: arm: Implement software vGICv2 emulation Date: Tue, 30 Jun 2015 11:16:03 +0300 Message-ID: <01c601d0b30d$01cad080$05607180$@samsung.com> References: <20150629125213.GK11332@cbox> <559151FE.8020701@arm.com> 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 F132856AA5 for ; Tue, 30 Jun 2015 04:04:56 -0400 (EDT) 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 W3t959q2pEU6 for ; Tue, 30 Jun 2015 04:04:55 -0400 (EDT) Received: from mailout4.w1.samsung.com (mailout4.w1.samsung.com [210.118.77.14]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 35CEC56A7B for ; Tue, 30 Jun 2015 04:04:54 -0400 (EDT) Received: from eucpsbgm2.samsung.com (unknown [203.254.199.245]) by mailout4.w1.samsung.com (Oracle Communications Messaging Server 7.0.5.31.0 64bit (built May 5 2014)) with ESMTP id <0NQR00IZX0ASS760@mailout4.w1.samsung.com> for kvmarm@lists.cs.columbia.edu; Tue, 30 Jun 2015 09:16:04 +0100 (BST) In-reply-to: <559151FE.8020701@arm.com> Content-language: ru 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: 'Andre Przywara' , 'Christoffer Dall' Cc: 'Marc Zyngier' , kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org List-Id: kvmarm@lists.cs.columbia.edu Hello! > I wonder if these patches would pave the way to support running GICv2 > guests on GICv3s without compat support? Yes, it does. I haven't implemented GICv3 bit for this time, but - yes. And it will be a very small addition. > Pavel, is this "broken" GIC you are talking about going to appear in a > publicly available SoC? In kernel documentation it's known as "FrankenGIC". First of all, it's Exynos 4 (however i don't know whether it implements virtualization extensions). Second, it is present in many consumer electronics products (does this count as "publicly available"? But you can learn this fact from Samsung's opensource releases). I use one of these boards for my tests because we have lots of them here :) Third, this code doesn't really depend on hardware GIC, and can be reused on RPi-2 with a little more hacking. Fourth, there is at least of one ARM64 machine with broken vGICv3. And you can buy it. I have it here. And it would also benefit from this code (yes, with GICv3 CPU interface emulation added, which becomes trivial). Kind regards, Pavel Fedin Expert Engineer Samsung Electronics Research center Russia