Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934389AbaDIXK4 (ORCPT ); Wed, 9 Apr 2014 19:10:56 -0400 Received: from mga02.intel.com ([134.134.136.20]:32380 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932996AbaDIXKy (ORCPT ); Wed, 9 Apr 2014 19:10:54 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,829,1389772800"; d="scan'208";a="490329543" Message-ID: <5345D360.5000506@linux.intel.com> Date: Wed, 09 Apr 2014 16:10:24 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.4.0 MIME-Version: 1.0 To: Fengguang Wu , Jet Chen , Paolo Bonzini , Borislav Petkov CC: "Romer, Benjamin M" , LKML Subject: Re: [visorchipset] invalid opcode: 0000 [#1] PREEMPT SMP References: <20140407111725.GC25152@localhost> <53444220.50009@intel.com> <53458A3A.1050608@intel.com> <20140409230114.GB8370@localhost> In-Reply-To: <20140409230114.GB8370@localhost> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/09/2014 04:01 PM, Fengguang Wu wrote: > CC the KVM people: it looks like a KVM problem that can be triggered by > > qemu-system-x86_64 -cpu Haswell,+smep,+smap I'm really confused. First of all, is this a KVM problem or is it a Qemu JIT problem? Either seems really wonky. It is questionable at best whether or not Qemu in JIT mode should set the hypervisor bit IMO. However, even so, you *better* not call VMCALL *just* because the hypervisor bit is set. The reason for it is that you have absolutely no idea what VMCALL is going to do on any one hypervisor... different hypervisors even use completely different conventions for VMCALL, and some might not accept VMCALL at all and might just terminate your guest with extreme prejudice. So what is actually going on here? -hpa -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/