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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 82980C5ACAE for ; Wed, 11 Sep 2019 15:54:29 +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 5A3F32089F for ; Wed, 11 Sep 2019 15:54:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5A3F32089F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:52928 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i84wt-0004Xn-M1 for qemu-devel@archiver.kernel.org; Wed, 11 Sep 2019 11:54:27 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:59952) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i84uP-0002Jp-Rl for qemu-devel@nongnu.org; Wed, 11 Sep 2019 11:51:55 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1i84uO-00039P-No for qemu-devel@nongnu.org; Wed, 11 Sep 2019 11:51:53 -0400 Received: from mx1.redhat.com ([209.132.183.28]:55328) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1i84uJ-00036x-A1; Wed, 11 Sep 2019 11:51:48 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8477310F23E0; Wed, 11 Sep 2019 15:51:44 +0000 (UTC) Received: from laptop.redhat.com (ovpn-116-168.ams2.redhat.com [10.36.116.168]) by smtp.corp.redhat.com (Postfix) with ESMTP id CF5B060852; Wed, 11 Sep 2019 15:51:41 +0000 (UTC) From: Eric Auger To: eric.auger.pro@gmail.com, eric.auger@redhat.com, qemu-devel@nongnu.org, qemu-arm@nongnu.org, peter.maydell@linaro.org Date: Wed, 11 Sep 2019 17:51:25 +0200 Message-Id: <20190911155125.11932-4-eric.auger@redhat.com> In-Reply-To: <20190911155125.11932-1-eric.auger@redhat.com> References: <20190911155125.11932-1-eric.auger@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (mx1.redhat.com [10.5.110.66]); Wed, 11 Sep 2019 15:51:44 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [RFC v2 3/3] virt: Check KVM_CAP_ARM_IRQ_LINE_LAYOUT_2 for smp_cpus > 256 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, maz@kernel.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Host kernel within [4.18, 5.3] report an erroneous KVM_MAX_VCPUS=3D512 for ARM. The actual capability to instantiate more than 256 vcpus was fixed in 5.4 with the upgrade of the KVM_IRQ_LINE ABI to support vcpu id encoded on 12 bits instead of 8 and a redistributor consuming a single KVM IO device instead of 2. So let's check this capability when attempting to use more than 256 vcpus. Signed-off-by: Eric Auger --- hw/arm/virt.c | 4 ++++ target/arm/kvm.c | 21 +++++++++++++++++++++ target/arm/kvm_arm.h | 15 +++++++++++++++ 3 files changed, 40 insertions(+) diff --git a/hw/arm/virt.c b/hw/arm/virt.c index 0d1629ccb3..465e3140f7 100644 --- a/hw/arm/virt.c +++ b/hw/arm/virt.c @@ -1575,6 +1575,10 @@ static void machvirt_init(MachineState *machine) virt_max_cpus =3D GIC_NCPU; } =20 + if (kvm_arm_irq_line_layout_mismatch(MACHINE(vms), max_cpus)) { + exit(1); + } + if (max_cpus > virt_max_cpus) { error_report("Number of SMP CPUs requested (%d) exceeds max CPUs= " "supported by machine 'mach-virt' (%d)", diff --git a/target/arm/kvm.c b/target/arm/kvm.c index 6cdfa2204f..b601e2f35a 100644 --- a/target/arm/kvm.c +++ b/target/arm/kvm.c @@ -171,6 +171,27 @@ bool kvm_arm_pmu_supported(CPUState *cpu) return kvm_check_extension(s, KVM_CAP_ARM_PMU_V3); } =20 +bool kvm_arm_irq_line_layout_mismatch(MachineState *ms, int vcpus) +{ + KVMState *s; + bool ret; + + if (!kvm_enabled()) { + return false; + } + + s =3D KVM_STATE(ms->accelerator); + + ret =3D vcpus > 256 && + !kvm_check_extension(s, KVM_CAP_ARM_IRQ_LINE_LAYOUT_2); + + if (ret) { + error_report("Using more than 256 vcpus requires a host kernel " + "with KVM_CAP_ARM_IRQ_LINE_LAYOUT_2"); + } + return ret; +} + int kvm_arm_get_max_vm_ipa_size(MachineState *ms) { KVMState *s =3D KVM_STATE(ms->accelerator); diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h index b4e19457a0..d893d950d8 100644 --- a/target/arm/kvm_arm.h +++ b/target/arm/kvm_arm.h @@ -233,6 +233,16 @@ bool kvm_arm_pmu_supported(CPUState *cs); */ int kvm_arm_get_max_vm_ipa_size(MachineState *ms); =20 +/** + * kvm_arm_irq_line_layout_mismatch - Returns whether the number of vcpu= s + * exceeds the limit imposed by the legacy KVM_IRQ_LINE ARM layout + * (without the vcpu2_index field). + * + * @ms: Machine state handle + * @vcpus: number of vcpus + */ +bool kvm_arm_irq_line_layout_mismatch(MachineState *ms, int vcpus); + /** * kvm_arm_sync_mpstate_to_kvm * @cpu: ARMCPU @@ -281,6 +291,11 @@ static inline int kvm_arm_get_max_vm_ipa_size(Machin= eState *ms) return -ENOENT; } =20 +static inline bool kvm_arm_irq_line_layout_mismatch(MachineState *ms, in= t vcpus) +{ + return false; +} + static inline int kvm_arm_vgic_probe(void) { return 0; --=20 2.20.1