From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andre Przywara Subject: Re: This combination of AMDprocessors is not suitable for SMP? Date: Thu, 23 Jul 2009 12:34:40 +0200 Message-ID: <4A683CC0.90509@amd.com> References: <4A6816AD.2060700@msgid.tls.msk.ru> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Cc: Linux-kernel , KVM list To: Michael Tokarev Return-path: In-Reply-To: <4A6816AD.2060700@msgid.tls.msk.ru> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org Michael Tokarev wrote: > (yes there's no typo in $subject, it's an old formatting > bug in printk). > > When booting kvm guest on an AMD CPU, guest kernel prints > this warning: > > WARNING: This combination of AMDprocessors is not suitable for SMP. > > be it SMP or UP guest. What's wrong with this "combination", > and can it be fixed? The qemu64 CPU model KVM injects into the guest lets it see an AMD K7 with 64bit extension. Only some AMD K7 (Athlon-MP) were certified for SMP support, so this code warns the user about an unsupported hardware. When running KVM you can ignore this warning, as it only applies to non-KVM capable processors and has no meaning for virtual SMP anyway. If you like this warning to disappear, you can use "-cpu host" (and probably loose migration capability) or wait for the new safe64 CPU type, which will use family 15 instead of 6. Regards, Andre. -- Andre Przywara AMD-Operating System Research Center (OSRC), Dresden, Germany Tel: +49 351 448 3567 12 ----to satisfy European Law for business letters: Advanced Micro Devices GmbH Karl-Hammerschmidt-Str. 34, 85609 Dornach b. Muenchen Geschaeftsfuehrer: Thomas M. McCoy; Giuliano Meroni Sitz: Dornach, Gemeinde Aschheim, Landkreis Muenchen Registergericht Muenchen, HRB Nr. 43632