From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:42911) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TLdRe-0006Vf-DQ for qemu-devel@nongnu.org; Tue, 09 Oct 2012 13:18:15 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TLdRc-0003yy-30 for qemu-devel@nongnu.org; Tue, 09 Oct 2012 13:18:14 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42535) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TLdRb-0003yW-Or for qemu-devel@nongnu.org; Tue, 09 Oct 2012 13:18:12 -0400 Date: Tue, 9 Oct 2012 14:18:05 -0300 From: Marcelo Tosatti Message-ID: <20121009171805.GA26004@amt.cnet> References: <1348497138-2516-1-git-send-email-Don@CloudSwitch.com> <1348497138-2516-6-git-send-email-Don@CloudSwitch.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1348497138-2516-6-git-send-email-Don@CloudSwitch.com> Subject: Re: [Qemu-devel] [PATCH v6 05/16] target-i386: Use Hypervisor level in -machine pc, accel=kvm. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Don Slutz Cc: peter.maydell@linaro.org, ehabkost@redhat.com, kvm@vger.kernel.org, qemu-devel@nongnu.org, avi@redhat.com, anthony@codemonkey.ws, imammedo@redhat.com, afaerber@suse.de On Mon, Sep 24, 2012 at 10:32:07AM -0400, Don Slutz wrote: > Also known as Paravirtualization level. > > This change is based on: > > Microsoft Hypervisor CPUID Leaves: > http://msdn.microsoft.com/en-us/library/windows/hardware/ff542428%28v=vs.85%29.aspx > > Linux kernel change starts with: > http://fixunix.com/kernel/538707-use-cpuid-communicate-hypervisor.html > Also: > http://lkml.indiana.edu/hypermail/linux/kernel/1205.0/00100.html > > VMware documention on CPUIDs (Mechanisms to determine if software is > running in a VMware virtual machine): > http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1009458 > > QEMU knows this is KVM_CPUID_SIGNATURE (0x40000000). > > Signed-off-by: Don Slutz > --- > target-i386/kvm.c | 4 ++-- > 1 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/target-i386/kvm.c b/target-i386/kvm.c > index 895d848..8462c75 100644 > --- a/target-i386/kvm.c > +++ b/target-i386/kvm.c > @@ -389,12 +389,12 @@ int kvm_arch_init_vcpu(CPUX86State *env) > c = &cpuid_data.entries[cpuid_i++]; > memset(c, 0, sizeof(*c)); > c->function = KVM_CPUID_SIGNATURE > - if (!hyperv_enabled()) { > + if (!env->cpuid_hv_level_set) { > memcpy(signature, "KVMKVMKVM\0\0\0", 12); > c->eax = 0; > } else { > memcpy(signature, "Microsoft Hv", 12); > - c->eax = HYPERV_CPUID_MIN; > + c->eax = env->cpuid_hv_level; This breaks hyperv_enabled() checks. Don, are you certain it is worthwhile to make this configurable? Can you explain why, under your scenario, it is worthwhile? Because these are separate problems: - "Fake" VMWare hypervisor (which seems to be your main goal). - Make CPUID HV leafs configurable via command line. My point is that the CPUIDs must be carefully constructed, that i miss the point why making them configurable is desired.