From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gleb Natapov Subject: Re: [PATCH] Print Guest VMCS state on vmexit failure Date: Tue, 20 Oct 2009 09:57:46 +0200 Message-ID: <20091020075746.GI29477@redhat.com> References: <1256025045-4972-1-git-send-email-clalance@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: kvm@vger.kernel.org To: Chris Lalancette Return-path: Received: from mx1.redhat.com ([209.132.183.28]:27980 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750976AbZJTH5o (ORCPT ); Tue, 20 Oct 2009 03:57:44 -0400 Received: from int-mx04.intmail.prod.int.phx2.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.17]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id n9K7vmY2009217 for ; Tue, 20 Oct 2009 03:57:49 -0400 Content-Disposition: inline In-Reply-To: <1256025045-4972-1-git-send-email-clalance@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On Tue, Oct 20, 2009 at 09:50:45AM +0200, Chris Lalancette wrote: > If we fail to handle a VMEXIT for some reason, print out a lot > more debugging information about the state of the GUEST VMCS > area. This does not fix a bug, but helps a lot when trying to > track down the cause of a VMEXIT/VMENTRY failure. > > Signed-off-by: Chris Lalancette > --- > arch/x86/kvm/vmx.c | 38 ++++++++++++++++++++++++++++++++++++++ > 1 files changed, 38 insertions(+), 0 deletions(-) > > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c > index 311afd4..37b1682 100644 > --- a/arch/x86/kvm/vmx.c > +++ b/arch/x86/kvm/vmx.c > @@ -3452,6 +3452,14 @@ static int (*kvm_vmx_exit_handlers[])(struct kvm_vcpu *vcpu) = { > static const int kvm_vmx_max_exit_handlers = > ARRAY_SIZE(kvm_vmx_exit_handlers); > > +#define PRINT_GUEST_SEGMENT(seg) do { \ > + printk(KERN_DEBUG #seg ": SELECTOR 0x%lx, BASE 0x%lx, LIMIT 0x%lx, AR 0x%lx\n", \ > + vmcs_readl(GUEST_##seg##_SELECTOR), \ > + vmcs_readl(GUEST_##seg##_BASE), \ > + vmcs_readl(GUEST_##seg##_LIMIT), \ > + vmcs_readl(GUEST_##seg##_AR_BYTES)); \ > + while(0) > + > /* > * The guest has exited. See if we can fix it or if we need userspace > * assistance. > @@ -3512,6 +3520,36 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu) > else { > vcpu->run->exit_reason = KVM_EXIT_UNKNOWN; > vcpu->run->hw.hardware_exit_reason = exit_reason; > + > + printk(KERN_DEBUG "GUEST STATE:\n"); > + printk(KERN_DEBUG "CR0: 0x%lx\n", vmcs_readl(GUEST_CR0)); > + printk(KERN_DEBUG "CR3: 0x%lx\n", vmcs_readl(GUEST_CR3)); > + printk(KERN_DEBUG "CR4: 0x%lx\n", vmcs_readl(GUEST_CR4)); > + printk(KERN_DEBUG "VMENTRY CONTROL: 0x%lx\n", > + vmcs_readl(VM_ENTRY_CONTROLS)); > + printk(KERN_DEBUG "DR7: 0x%lx\n", vmcs_readl(GUEST_DR7)); > + printk(KERN_DEBUG "SYSENTER ESP: 0x%lx\n", > + vmcs_readl(GUEST_SYSENTER_ESP)); > + printk(KERN_DEBUG "SYSENTER EIP: 0x%lx\n", > + vmcs_readl(GUEST_SYSENTER_EIP)); > + > + PRINT_GUEST_SEGMENT(CS); > + PRINT_GUEST_SEGMENT(SS); > + PRINT_GUEST_SEGMENT(DS); > + PRINT_GUEST_SEGMENT(ES); > + PRINT_GUEST_SEGMENT(FS); > + PRINT_GUEST_SEGMENT(GS); > + PRINT_GUEST_SEGMENT(TR); > + PRINT_GUEST_SEGMENT(LDTR); > + > + printk(KERN_DEBUG "GDTR: BASE 0x%lx, LIMIT 0x%lx", > + vmcs_readl(GUEST_GDTR_BASE), > + vmcs_readl(GUEST_GDTR_LIMIT)); > + printk(KERN_DEBUG "IDTR: BASE 0x%lx, LIMIT 0x%lx", > + vmcs_readl(GUEST_IDTR_BASE), > + vmcs_readl(GUEST_IDTR_LIMIT)); > + printk(KERN_DEBUG "RIP: 0x%lx\n",vmcs_readl(GUEST_RIP)); > + printk(KERN_DEBUG "RFLAGS: 0x%lx\n",vmcs_readl(GUEST_RFLAGS)); > } > return 0; Move this to separate function may be? vmx_handle_exit() will be hard to read with this blob in the middle. -- Gleb.