From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zdenek Kaspar Subject: Re: linux-4.4: qemu starting VM emits vmwrite error Date: Tue, 12 Jan 2016 18:58:16 +0100 Message-ID: <56953EB8.5080403@gmail.com> References: <5693F235.5010309@gmail.com> <1452587122.4846.3.camel@intel.com> <5694D881.1090709@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit To: Paolo Bonzini , "Han, Huaitong" , "kvm@vger.kernel.org" Return-path: Received: from mail-wm0-f51.google.com ([74.125.82.51]:33837 "EHLO mail-wm0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752185AbcALR6T (ORCPT ); Tue, 12 Jan 2016 12:58:19 -0500 Received: by mail-wm0-f51.google.com with SMTP id u188so266466541wmu.1 for ; Tue, 12 Jan 2016 09:58:19 -0800 (PST) In-Reply-To: <5694D881.1090709@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On 01/12/2016 11:42 AM, Paolo Bonzini wrote: > > > On 12/01/2016 09:25, Han, Huaitong wrote: >> I don't have a old machine to test it, please patch it and give me >> feedback. Thanks a lot. >> >> From f06a85c76db210ce7145be6c704c44a9cef70ee3 Mon Sep 17 00:00:00 2001 >> From: Huaitong Han >> Date: Tue, 12 Jan 2016 16:04:20 +0800 >> Subject: [PATCH] kvm: x86: Fix vmwrite to SECONDARY_VM_EXEC_CONTROL >> >> SECONDARY_VM_EXEC_CONTROL vmcs will be updated with vmx_cpuid_update, >> but it >> will vmwrite error on the older CPU because the code is written without >> CPU_BASED_ACTIVATE_SECONDARY_CONTROLS check. >> >> This will get rid of the following trace: >> >> vmwrite error: reg 401e value 10 (err 12) >> Call Trace: >> [] ? dump_stack+0x40/0x57 >> [] ?vmx_cpuid_update+0x5d/0x150 [kvm_intel] >> [] ?kvm_vcpu_ioctl_set_cpuid2+0x4c/0x70 [kvm] >> [] ?kvm_arch_vcpu_ioctl+0x903/0xfa0 [kvm] >> >> Signen-off-by: Huaitong Han >> --- >> arch/x86/kvm/vmx.c | 7 +++++-- >> 1 file changed, 5 insertions(+), 2 deletions(-) >> >> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c >> index 44976a5..80f21d3 100644 >> --- a/arch/x86/kvm/vmx.c >> +++ b/arch/x86/kvm/vmx.c >> @@ -8904,7 +8904,7 @@ static void vmx_cpuid_update(struct kvm_vcpu >> *vcpu) >> { >> struct kvm_cpuid_entry2 *best; >> struct vcpu_vmx *vmx = to_vmx(vcpu); >> - u32 secondary_exec_ctl = vmx_secondary_exec_control(vmx); >> + u32 secondary_exec_ctl = -1; >> >> if (vmx_rdtscp_supported()) { >> bool rdtscp_enabled = guest_cpuid_has_rdtscp(vcpu); >> @@ -8932,7 +8932,10 @@ static void vmx_cpuid_update(struct kvm_vcpu >> *vcpu) >> best->ebx &= ~bit(X86_FEATURE_INVPCID); >> } >> >> - vmcs_set_secondary_exec_control(secondary_exec_ctl); >> + if (cpu_has_secondary_exec_ctrls()) { >> + secondary_exec_ctl &= vmx_secondary_exec_control(vmx); >> + vmcs_set_secondary_exec_control(secondary_exec_ctl); >> + } >> >> if (static_cpu_has(X86_FEATURE_PCOMMIT) && nested) { >> if (guest_cpuid_has_pcommit(vcpu)) >> > > > Looks good, thanks! > > Paolo > Patch tested and works as expected. I see it's queued for v4.5 and with stable tag, so thank you both. Z.