Re: [PATCH] KVM: nVMX: Fix L2 fails to boot due to VM entry with invalid control field

From: Paolo Bonzini
Date: Wed Feb 15 2017 - 06:35:25 EST




On 15/02/2017 12:33, David Hildenbrand wrote:
> Am 15.02.2017 um 12:10 schrieb Wanpeng Li:
>> From: Wanpeng Li <wanpeng.li@xxxxxxxxxxx>
>>
>> When I run kvm-unit-tests/vmx.flat in L1, The L2 fails to boot due to VM
>> entry with invalid control field.
>>
>> KVM: entry failed, hardware error 0x7
>> EAX=00000000 EBX=00000000 ECX=00000000 EDX=000306c3
>> ESI=00000000 EDI=00000000 EBP=00000000 ESP=00000000
>> EIP=0000fff0 EFL=00000002 [-------] CPL=0 II=0 A20=1 SMM=0 HLT=0
>> ES =0000 00000000 0000ffff 00009300
>> CS =f000 ffff0000 0000ffff 00009b00
>> SS =0000 00000000 0000ffff 00009300
>> DS =0000 00000000 0000ffff 00009300
>> FS =0000 00000000 0000ffff 00009300
>> GS =0000 00000000 0000ffff 00009300
>> LDT=0000 00000000 0000ffff 00008200
>> TR =0000 00000000 0000ffff 00008b00
>> GDT= 00000000 0000ffff
>> IDT= 00000000 0000ffff
>> CR0=60000010 CR2=00000000 CR3=00000000 CR4=00000000
>> DR0=0000000000000000 DR1=0000000000000000 DR2=0000000000000000 DR3=0000000000000000
>> DR6=00000000ffff0ff0 DR7=0000000000000400
>> EFER=0000000000000000
>>
>> nested_get_vmcs12_pages() fails to set VIRTUAL_APIC_PAGE_ADDR field in
>> vmcs02 even if acquires a virtual apic page. This patch fixes it by
>> setting VIRTUAL_APIC_PAGE_ADDR field in vmcs02 once acquires a virtual
>> apic page.
>>
>> Signed-off-by: Wanpeng Li <wanpeng.li@xxxxxxxxxxx>
>> ---
>> arch/x86/kvm/vmx.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
>> index 204d6e6..650f3433 100644
>> --- a/arch/x86/kvm/vmx.c
>> +++ b/arch/x86/kvm/vmx.c
>> @@ -9685,7 +9685,7 @@ static void nested_get_vmcs12_pages(struct kvm_vcpu *vcpu,
>> * control. But such a configuration is useless, so
>> * let's keep the code simple.
>> */
>> - if (!vmx->nested.virtual_apic_page) {
>> + if (vmx->nested.virtual_apic_page) {
>> hpa = page_to_phys(vmx->nested.virtual_apic_page);
>> vmcs_write64(VIRTUAL_APIC_PAGE_ADDR, hpa);
>> }
>>
>
> On which branch is this?

It's kvm/queue, which has a WIP (and mostly untested) version of Jim's
nVMX checkpointing patches.

Paolo