Re: [Bug 50921] kvm hangs booting Windows 2000

[Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>]

On 11/24/2012 09:44 PM, bugzilla-daemon@bugzilla.kernel.org wrote:
> https://bugzilla.kernel.org/show_bug.cgi?id=50921
> 
> 
> 
> 
> 
> --- Comment #5 from Lucio Crusca <lucio@sulweb.org>  2012-11-24 13:44:16 ---
> Here the first tests results:
> 
> vbox modules do not make a difference (tried rmmod vboxpci vboxnetadp
> vboxnetflt vboxdrv and then kvm ...).
> 
> The trace.dat is about 60M, I could upload it somewhere, however I tried
> looking at it and I'm reasonably sure it hangs here:
> 
> $ trace-cmd report | grep 125\\.332 | tail
>              kvm-6588  [000]   125.332264: kvm_entry:            vcpu 0
>              kvm-6588  [000]   125.332264: kvm_emulate_insn:     10000:44f8: 75
> 27

Hmm... no 'kvm_exit' message. It looks like the infinite loop is caused by:

|	/* Don't enter VMX if guest state is invalid, let the exit handler
|	   start emulation until we arrive back to a valid state */
|	if (vmx->emulation_required && emulate_invalid_guest_state)
|		return;

(vmx_vcpu_run in arch/x86/kvm/vmx.c)

And, i noticed 'ept' is not supported on your box, that means
'enable_unrestricted_guest' is disabled. I guess something was wrong
when emulate big real mode.

Could you reload kvm-intel.ko with 'emulate_invalid_guest_state = 0',
and see what will happen.