From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51022) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Xbbpp-00037l-3t for qemu-devel@nongnu.org; Tue, 07 Oct 2014 16:58:26 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Xbbpg-00052u-1s for qemu-devel@nongnu.org; Tue, 07 Oct 2014 16:58:17 -0400 Received: from mail-qa0-x229.google.com ([2607:f8b0:400d:c00::229]:49899) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Xbbpf-00051Z-Rx for qemu-devel@nongnu.org; Tue, 07 Oct 2014 16:58:08 -0400 Received: by mail-qa0-f41.google.com with SMTP id n8so4944834qaq.14 for ; Tue, 07 Oct 2014 13:58:06 -0700 (PDT) Sender: Paolo Bonzini Message-ID: <543453D9.8020706@redhat.com> Date: Tue, 07 Oct 2014 22:58:01 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: <1412711059-12524-1-git-send-email-wei@redhat.com> In-Reply-To: <1412711059-12524-1-git-send-email-wei@redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 1/1] target-i386: prevent users from setting threads>1 for AMD CPUs List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Wei Huang , afaerber@suse.de Cc: qemu-devel@nongnu.org Il 07/10/2014 21:44, Wei Huang ha scritto: > AMD CPU doesn't support hyperthreading. Even though QEMU fixes > this issue by setting CPUID_0000_0001_EBX and CPUID_8000_0008_ECX > via conversion, it is better to stop end-users in the first place > with a warning message. Hi Wei, what exactly breaks if you try creating an AMD VM with hyperthreading? I am worried that the default CPU is an AMD one when KVM is disabled, and thus "qemu-system-x86_64 -smp threads=2" will likely be broken. Paolo