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=-1.0 required=3.0 tests=MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 BB8E8C4360C for ; Fri, 4 Oct 2019 04:34:34 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8C8A420862 for ; Fri, 4 Oct 2019 04:34:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8C8A420862 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:42240 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iGFIX-0003CE-Nq for qemu-devel@archiver.kernel.org; Fri, 04 Oct 2019 00:34:33 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:36766) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iG594-0007oE-8h for qemu-devel@nongnu.org; Thu, 03 Oct 2019 13:44:07 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iG593-0003ql-7Z for qemu-devel@nongnu.org; Thu, 03 Oct 2019 13:44:06 -0400 Received: from inca-roads.misterjones.org ([213.251.177.50]:37821) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iG593-0003po-1Z; Thu, 03 Oct 2019 13:44:05 -0400 Received: from 78.163-31-62.static.virginmediabusiness.co.uk ([62.31.163.78] helo=big-swifty.misterjones.org) by cheepnis.misterjones.org with esmtpsa (TLSv1.2:AES256-GCM-SHA384:256) (Exim 4.80) (envelope-from ) id 1iG58y-00052p-Py; Thu, 03 Oct 2019 19:44:00 +0200 Date: Thu, 03 Oct 2019 18:43:59 +0100 Message-ID: <86d0fdrag0.wl-maz@kernel.org> From: Marc Zyngier To: Eric Auger Subject: Re: [PATCH v4 0/3] KVM/ARM: Fix >256 vcpus In-Reply-To: <20191003154640.22451-1-eric.auger@redhat.com> References: <20191003154640.22451-1-eric.auger@redhat.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL/10.8 EasyPG/1.0.0 Emacs/26 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 62.31.163.78 X-SA-Exim-Rcpt-To: eric.auger@redhat.com, eric.auger.pro@gmail.com, qemu-devel@nongnu.org, qemu-arm@nongnu.org, peter.maydell@linaro.org, yuzenghui@huawei.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on cheepnis.misterjones.org); SAEximRunCond expanded to false X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [fuzzy] X-Received-From: 213.251.177.50 X-Mailman-Approved-At: Fri, 04 Oct 2019 00:33:47 -0400 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: yuzenghui@huawei.com, peter.maydell@linaro.org, qemu-arm@nongnu.org, qemu-devel@nongnu.org, eric.auger.pro@gmail.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Thu, 03 Oct 2019 16:46:37 +0100, Eric Auger wrote: > > Since 4.18, KVM/ARM exposes a KVM_MAX_VCPUS equal to 512. However it was > reported [1] that a VM with more than 256 vcpus cannot be launched. 5.4 > fixes the situation with 2 patches: > - one upgrade of the KVM_IRQ_LINE API [2] supporting a vcpu id encoded > on 12 bits, > - the reduction of KVM IO devices consumed by each GICv3 redistributor [3] > > This series uses the new KVM_IRQ_LINE API and also checks the associated > capability (KVM_CAP_ARM_IRQ_LINE_LAYOUT_2) in machvirt. > > Without the series, as soon as the -smp arguments exceeds 256, QEMU exits > with "kvm_set_irq: Invalid argument". FWIW, and for the whole series: Acked-by: Marc Zyngier M. -- Jazz is not dead, it just smells funny.