From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36112) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bWgNA-00081w-T5 for qemu-devel@nongnu.org; Mon, 08 Aug 2016 04:57:25 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bWgN5-0006DK-Vu for qemu-devel@nongnu.org; Mon, 08 Aug 2016 04:57:24 -0400 Received: from mx1.redhat.com ([209.132.183.28]:56328) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bWgN5-0006DB-QA for qemu-devel@nongnu.org; Mon, 08 Aug 2016 04:57:19 -0400 Date: Mon, 8 Aug 2016 16:57:14 +0800 From: Peter Xu Message-ID: <20160808085714.GG3825@pxdev.xzpeter.org> References: <1470390377-228219-1-git-send-email-imammedo@redhat.com> <20160808074123.GA32205@g.c> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20160808074123.GA32205@g.c> Subject: Re: [Qemu-devel] [PATCH for-2.8 00/18] pc: q35: x2APIC support in kvm_apic mode List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Igor Mammedov , qemu-devel@nongnu.org, rkrcmar@redhat.com, ehabkost@redhat.com, mst@redhat.com, mtosatti@redhat.com, kevin@koconnor.net, pbonzini@redhat.com, lersek@redhat.com, tianyu.lan@intel.com, yong.y.wang@intel.com On Mon, Aug 08, 2016 at 03:41:23PM +0800, Chao Gao wrote: > HI, everyone. > > We have done some tests after merging this patch set into the lastest qemu > master. In kvm aspect, we use the lastest kvm linux-next branch. Here are > some problems we have met. > > 1. We can't boot up a 288 vcpus linux guest with CLI: > qemu-system-x86_64 -boot c -m 4096 -sdl -monitor pty --enable-kvm \ > -M kernel-irqchip=split -serial stdio -bios bios.bin -smp cpus=288 \ > -hda vdisk.img -device intel-iommu,intremap=on -machine q35. > The problem exists, even after we only assign 32 vcpus to the linux guest. > Maybe the output "do_IRQ: 146.113 No irq handler for vector (irq -1)" is a clue. > The output of qemu and kernel is in attachments. Do you have any idea > about the problem and how to solve it? IIUC, we need to wait for Radim's QEMU patches to finally enable 288 vcpus? Btw, could you please try adding this to the QEMU cmdline when testing with 32 vcpus: -global ioapic.version=0x20 I see that you were running RHEL 7.2 guest with a default e1000. In that case, we may need to boost ioapic version to 0x20. Thanks, -- peterx