From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: [PATCH 1/2] KVM: VMX: Notify if VMX is already in use Date: Thu, 1 Dec 2011 20:30:17 +0200 Message-ID: <1322764218-4698-1-git-send-email-levinsasha928@gmail.com> Cc: Sasha Levin , Joerg Roedel , Avi Kivity , Marcelo Tosatti , kvm@vger.kernel.org To: linux-kernel@vger.kernel.org Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org Currently we silently fail if VMX is already in use by a different virtualization technology. This is bad since it's non-obvious for the user, and its not too uncommon for users to have several of these installed on same host. This patch adds a message to notify the user of the problem. Cc: Joerg Roedel Cc: Avi Kivity Cc: Marcelo Tosatti Cc: kvm@vger.kernel.org Signed-off-by: Sasha Levin --- arch/x86/kvm/vmx.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 4ceced2..0ef59ed 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -2300,8 +2300,11 @@ static int hardware_enable(void *garbage) u64 phys_addr = __pa(per_cpu(vmxarea, cpu)); u64 old, test_bits; - if (read_cr4() & X86_CR4_VMXE) + if (read_cr4() & X86_CR4_VMXE) { + printk(KERN_ERR "hardware_enable: VMX already in use on CPU%d. " + "Are you already another hypervisor?\n", cpu); return -EBUSY; + } INIT_LIST_HEAD(&per_cpu(loaded_vmcss_on_cpu, cpu)); rdmsrl(MSR_IA32_FEATURE_CONTROL, old); -- 1.7.8.rc4