Re: [Qemu-devel] in_asm substitute for accel=kvm:tcg

[Paolo Bonzini]

Il 19/09/2013 19:18, Andriy Gapon ha scritto:
> on 19/09/2013 19:53 Paolo Bonzini said the following:
>> 1) Can you try loading the kvm_intel module with
>> emulate_invalid_guest_state=0?
> 
> Will do.
> 
>> 2) What are the contents of fs and gs?  Why are they not zeroed?
>> Perhaps that is causing invalid guest state emulation to run, and then
>> something is triggering a bug in emulate_invalid_guest_state itself.
> 
> I will try to find this out.
> 
>> 3) What is at 0x9315?
> 
> This I can answer immediately.  It looks like this address even gets executed
> earlier:
>  qemu-system-x86-12024 [002] 278153.809990: kvm_emulate_insn:     0:9315:ea 1a
> 93 00 00 (real)
>  qemu-system-x86-12024 [002] 278153.809991: kvm_entry:            vcpu 0
>  qemu-system-x86-12024 [002] 278153.809992: kvm_emulate_insn:     0:931a:31 c0
> (real)
> 
> I guess it's a jump to 931a.

Yes, it is.

> Puzzling that later it becomes a jump to self.

I don't think that's what happens.  It's more likely that for some
reason the emulator mis-parses the instruction.

Please confirm with "info cpus" that QEMU is looping there (just in
case), and attach the output of "info registers" (you can use "-monitor
stdio" to do this and to answer question 2 from my previous email).

Paolo