Re: [Qemu-devel] [help] error: when install on nest-kvm

[Sheldon <shaohef@linux.vnet.ibm.com>]

On 11/05/2012 04:44 PM, Sheldon wrote:
> Hi all,
>
> There is an error when I install a RHEL or FC17 os on my nest-kvm.
>
> I find some error in the qemu log( attachment) as follow:
> KVM: entry failed, hardware error 0x7
>
>
> so I check the related code in kvm.c.
>
> int kvm_arch_handle_exit(CPUX86State *env, struct kvm_run *run)
> {
> uint64_t code;
> int ret;
>
> switch (run->exit_reason) {
> ...
> case KVM_EXIT_FAIL_ENTRY:
> code = run->fail_entry.hardware_entry_failure_reason;
> fprintf(stderr, "KVM: entry failed, hardware error 0x%" PRIx64 "\n",
> code);
> if (host_supports_vmx() && code == VMX_INVALID_GUEST_STATE) {
> fprintf(stderr,
> "\nIf you're running a guest on an Intel machine without "
> "unrestricted mode\n"
> "support, the failure can be most likely due to the guest "
> "entering an invalid\n"
> "state for Intel VT. For example, the guest maybe running "
> "in big real mode\n"
> "which is not supported on less recent Intel processors."
> "\n\n");
> }
> ret = -1;
> break;
> case KVM_EXIT_EXCEPTION:
> ...
> }
>
> From the code, I'm not sure error is caused by nest kvm.
> for the hardware_entry_failure_reason is 0x7 not VMX_INVALID_GUEST_STATE.
> but I'm not find where the hardware_entry_failure_reason is set. I 
> doubt it is set by KVM module in kernel.
>
> here is the environment:
> the guest hypervisor, a nest-kvm VM, OS is 3.6.1-1.fc17.x86_64. And it 
> does support VT.
  sorry the OS is 3.6.2-4.fc17.x86_64. not 3.6.1-1.fc17.x86_64.
> $ sudo cat /proc/cpuinfo |grep vmx
> flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
> mca cmov pat pse36 clflush mmx fxsr sse sse2 ss syscall nx pdpe1gb
> rdtscp lm constant_tsc arch_perfmon rep_good nopl pni pclmulqdq vmx
> ssse3 cx16 sse4_1 sse4_2 popcnt aes hypervisor lahf_lm
>
> The host: OS is 3.6.1-1.fc17.x86_64. CPU is Intel(R) Xeon(R) CPU 
> X5650. The host also opens the nested switch.
> $ cat /sys/module/kvm_intel/parameters/nested
> Y
>


-- 
Sheldon Feng(冯少合)<shaohef@linux.vnet.ibm.com>
IBM Linux Technology Center